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What’s wrong with bunny hands on dinosaurs?

I was reading a post by Brian Switek on his blog Laelops—which by the way, if you aren’t reading it, you should—about interpreting injuries on dinosaur bones. It’s an interesting read, but what caught my eye was a problem that I have seen in more places than I can count. He included this picture in his post. Take at look at the front limbs.


Plateosaurus. Credit: Brian Switek

The “hands” are pointed inwards. To get in this position, the elbows have to be turned outwards, using a rotation in the shoulders. But it also requires the hands to be pronated. To get what I mean by that, hold your hands forward with the palms up. When you do this, the two bones in your forearms—the ulna and the radius—are positioned side by side.

Picture18This position is called supination. Pronation requires the radius to rotate so that it crosses over the ulna. This can be done because of the construction of the elbow. The ulna is essentially the entire elbow joint, making it a hinge type joint. The radius is, for the most part, just along for the ride at the elbow. The head—the part at the elbow—is round, with a shallow indentation, which is surrounded by what is called the annular ligament. That ligament wraps around the radius, attaching it to the ulna, but never actually attaching to the radius itself, allowing the head to spin in the sling. It is that shape of the radius and the annular ligament that allows it to rotate freely, which makes our level of pronation possible.

Importantly, all tetrapods have the same bones. It was set in place from the first fish that developed bones to support their fins and remains that way all through the hundreds of millions of years to us today. However, not all animals have the same shape of the radial head. Some animals appear to not have both bones, but in reality, they do. They have just fused the bones together. But that fusion has consequences, just like altering the shape of the radial head.

Before we move on to dinosaurs and those consequences, it would be reasonable to ask about other animals to see if they show the same pattern. Let’s take a look at proboscideans, the family of elephants. They are large animals that have their palms facing downward.


This is an elephant skeleton on display at the Manchester Museum. They have a radius and ulna, just like humans. Theirs, however, do not swivel. Nevertheless, it is rotated so that the bones are not in parallel, but the two ends are twisted so that the radius is twisted over the ulna. Their forelimbs are in permanent pronation.

So what about dinosaurs? Let’s look at Dreadnaughtus, the giant sauropod.


This is Figure 2 from Lacovara et al. 2014. The radius and ulna are massive, as befits a giant quadruped. They are also incapable of rotating to pronate the foot. It has been said by some that some degree of pronation is required for efficient quadrupedal locomotion, but that is not really accurate. It does mean though, that the first digit, what would be our thumb, is going to face forward or at most slightly inward while the remaining digits will be angled outward (anterolaterally). They will not be situated directly forward without shifting the arms at the shoulder. As an example, here is a figure showing a sauropod trackway. Note the direction of the toes.


This is a figure from Falkingham, et al. 2010. As can be seen, the toes are not forward, but pointing outward. The level of pronation is minor and can be achieved with only rotation at the shoulder and a minimal shift or the forelimb. VanBuren and Bonnan (2013) found this was true in all quadrupedal dinosaurs.

This is a best case for pronation in dinosaurs and they can’t do the full pronation needed for bunny hands, much less the bizarre inward facing hands of the Plateosaurus above. So let’s look at theropods, where we see bunny hands all the time. For instance, in Jurassic Park pretty much all the dinosaurs have bunny hands.


The palms are downward with the arms close in, requiring a full pronation to achieve that position. So could they do it? To the bones. This is the radius of Neuquenraptor, as published by Novas and Pol in 2005. It is an unenlagiin, in the family Dromaeosauridae, along with Velociraptor, Deinonychus, and all those other raptor dinosaurs.


These radius is fairly straight, and if you look at the head, it is not the shallowly indented round cup we see in mammals. It is more angular, which is typical of theropods. That relative angularity would prevent the radius from rotating as ours do, in effect locking it into a small range of motion, preventing them from placing their hands palm down.

In point of fact, VanBuren and Bonnan didn’t just look at sauropods. They looked at all types of dinosaurs. They found that no dinosaur had the ability to cross the radius over the ulna, which means that at best, they had very limited ability to pronate their forearms. That means no known dinosaur could have characteristically held their arms close in with their palms facing downward, aka bunny hands.

It is a little more complicated than this. Studies have shown that if the arm is fully extended, the hands can be more pronated, by using the entire length of the arm to rotate, but even that is not going to be fully pronated like we can, or bunnies can. And if you think about the living dinosaurs, the birds, when was the last time you saw a bird put its wings flat on the ground in front of them? They can clap, but they can’t type or play basketball.

Of course, the wrist bones of the maniraptors—those dinosaurs leading up to birds—did have what is called a semilunate carpal bone, allowing them to move their hands to insane degrees side to side, which is what allowed them to develop the ability to fold their wings like they do, and they can flex and extend their hands to a remarkable degree. But they cannot rotate their wrist. Try it yourself. See what movements you can make with your hand without moving your forearm, just your hand. However far you can move your hand that way, these dinosaurs have you beat in spades. But once you move that forearm, you have a serious advantage over them.



Real, Replica, or Fake

One question I get asked a lot when I show fossils to people is “Is it real or fake?” It is a question that always irks me because it seems very few people understand that this is an entirely wrong question.

People like to categorize things into binary bins. Is it black or white? Republican or Democrat? Is it raining or not? Do you accept science or religion? Of course, none of these questions make any sense as an either/or question. Just like real or fake, all of these questions miss the fact that there is more to it than one or the other. All of them can only be correctly answered if one is cognizant of the other variations. So today, I am going to introduce to you a more nuanced view of whether or not the fossils you see in museums are real or not.

Real fossils need little explanation. They are the actual fossil material. Whether or not it is actual bone or shell being preserved, a bone that has been replaced with minerals, a natural mold, or other some such style of preservation, they are real.


This is a real plesiosaur vertebra found in (or thereabouts) Sevier County, Arkansas.

Real in this case does not mean it is remains of the actual organism, although it can be. Bone, shell, leaves, and other tissues can be preserved indefinitely under the right conditions. Usually however, they are replaced with minerals or remain only as impressions in the sediment. In any case, these are all real fossils. They are the original fossil found, dug up, and brought back to the institution or person to whom it belongs.

Replicas  are casts or molds made from the actual fossil. They are made to look as close as possible to the original fossil. These are made so that the original can be protected while the copy is shown to many more people than could see the original. Use of replicas allows copies to be put in the hands of many people all over the world. In many instances, the original is too fragile or heavy to safely transport.


This is a cast of a real apatosaur bone. The original would be far too heavy and fragile to haul around to classrooms all the time.

The important point about replicas is that they are not fakes. They are duplicates of a real fossil. In some cases, they can be even better than the real thing. After decades of handling, the original fossils can get worn or broken, with details once present no longer visible.


Photo of the Berlin Archaeopteryx taken by Dr. Dave Hone. This fossil used to have, among other things, feathers on the legs, which were removed during too extensive preparation.

Fakes, on the other hand, represent something that is not only not real, but never existed. Many fakes are designed to deceive and so are often called forgeries. The difference between what many people think of as forgeries and what we are talking about here is that forgeries are usually designed to trick people into thinking they are the real thing. A replica, if presented as the real thing, would be considered a forgery. However, in paleontology, most things described as forgeries are in reality fakes designed to deceive people into thinking a fiction is real. Fakes are never acceptable in museums unless explicitly labeled to indicate that they are fantasies. The Piltdown Man is an example of a fake. It was made with the express purpose of making people think it was real, when in fact it was created from bits of human and animal bones that were altered to make them look like they belonged to the same primitive human.

Archaeoraptor was another fake. This one adds a wrinkle in the topic though. Archaeoraptor was made by gluing pieces of different fossils together. The individual pieces were real, but the resulting chimera was a fake.


Archaeoraptor. The picture on the right shows the various pieces. See the hyperlink for the full story.

As Archaeoraptor shows, fakes don’t have to be unreal to be fictional. There are lots of fakes that are real fossils put together in intentionally misleading ways. In the case of Archaeoraptor, they were simply trying to make the fossils more spectacular so they could sell them for a higher price. Others are done to discredit scientists or simply as pranks for fun.


Surgeon’s photo of “Nessie”

Of course, there are plenty of fakes that are made up out of whole cloth. Numerous “human” footprints found with dinosaur tracks are nothing more than carvings designed to trick gullible people. I have personally seen several in which the tool markings were clearly visible. The most famous picture of the Loch Ness Monster, known as the surgeon’s photo, was a fake.


A supposedly human footprint stepped on by a dinosaur track. Neither human nor dinosaur tracks look like this in reality. This is a clear fake being passed off as evidence of creationism by Carl Baugh.

So remember, when you are going to a museum or looking at fossils from a paleontologist, you may be looking at real fossils or replicas. But you will never be looking at fakes. They may not be the original fossils, but they are not trying to mislead you or lie to you, which is what fakes are trying to do. If you really want to see fakes, try here or here. And please, don’t insult your local paleontologist by saying they are showing you fakes when all they are doing is showing you replicas of real fossils that you might otherwise never be able to see.

The Griffin and the Dinosaur

The Griffin and the Dinosaur by Marc Aronson review summary: Get it. put it in your library collections. It has science, history, sociology, and documents the efforts of the researcher so people can see how ideas are put together, all in an easy to read, accessible format. There is even a free online education guide, with classroom activities matched to sixth grade common core standards. Highly recommended for elementary and middle school libraries. To see why, read the full review below.

The Griffin and the Dinosaur: How Adrienne Mayor Discovered a Fascinating Link Between Myth and Science.

by Marc Aronson with Adrienne Mayor. Illustrated by Chris Muller

griffinanddinosaurPublication Date: 2014

National Geographic Society. ISBN: 978-1-4263-1108-6 (trade hardback) 978-1-4263-1109-3 (reinforced library binding) Available from Bound to Stay Bound Books

ATOS level: 7.4, AR quiz availability: reading practice, 1.0 AR points

Recommended: Grades 4-8

If you are looking for a book about dinosaurs or myths, get another book. But if you are looking for a book about how myths are made and how dinosaurs play into that, this is a great book. The story here is one of cultural interpretations of the natural world. Before people knew about dinosaurs, they found their bones and tried to explain them as best they could according to their worldview. This book tells of the search by one woman to unravel the origins of myths with the hypothesis that they began as most stories do, with a kernel of truth.

Adrienne Mayor has written two influential books, called The First Fossil Hunters and Fossil Legends of the First Americans, in which she lays out all her evidence to support the idea of dinosaur bones being the kernel of truth upon which some of the myths from the ancient Greeks and Romans and the native Americans were built. However, these books together run almost 900 pages, which, while interesting to the serious student, are a bit out of reach for the casual reader. The Griffin and the Dinosaur makes an excellent introduction to this work that is accessible for anyone who can read beyond the basic learning to read books.


Illustration by Chris Muller

Marc Aronson has written several books for children and young adults, mostly relating history in a way that people will actually read. The writing is clear, easy to follow, and relatable enough to keep most readers engaged. The book is illustrated with numerous photos of archaeological artifacts, historical photos and drawings, and the occasional dinosaur. There are too few dinosaurs for my taste, especially for a book with the word dinosaur in the title, but the book is focused on the history and myth interpretations, not dinosaurs. The photos are supplemented with illustrations by Chris Muller, which add to the feel of the book, connecting the bones to the imagination.

The book is split into eight chapters, each only a few pages long. The first chapter, “Prairie Girl”, describes Adrienne Mayor’s childhood and her developing interest in nature and ancient myths. The second chapter, “The Sound of Heat’, finds Adrienne in Athens studying ancient Greek manuscripts in Athens. I’m not too fond of this particular chapter. In a chapter only three pages long, two pages are taken up mostly describing the conditions of the library in which she studied. Only on the third page does Aronson talk about griffins and Mayor’s question about what kind of fossil animal might have inspired it. The last paragraph of the chapter tells of her discovery of the “monster of Samos”.


Illustration by Chris Muller

“Sketching Griffins”, the third chapter, describes her discovery of ancient bronze griffins on Samos, but only giraffe bones for the monster, which could not have inspired the myth. It does answer a question I have long wondered. How did an obviously wingless dinosaur become the winged griffin? The answer to that lies in the very earliest depictions of griffins, which did not have wings. The wings were added later as the myth of the griffin grew and became more fanciful. The other thing I like in this chapter is the discussion of search images. When people have an idea in their head of what something should look like, it aids them in identifying it quickly, but it blinds them to possibilities outside that image.

Chapter four deals with Adrienne changing her search image by more study of the development of the griffin myth through history as well as any connections others had made, which led her to the work of Othenio Abel, who had asserted the cyclopean myths came from mammoth skeletons.

Chapter five continues her search for the historical origins of the griffin tale. During this time, she discovers Triceratops, which she thought might be the kernel of truth behind the myth. This is a nice chapter because it shows that even big, embarrassing mistakes does not mean that one should give up. They merely teach you what you need to learn next.


Illustration by Chris Muller

“The Secrets of the Flaming Cliffs”, chapter six finally introduces Adrienne to Protoceratops, a small, beaked dinosaur that was found associated with eggs in a nest. It had a small frill and a long scapula, or shoulder blade, which could have been mistaken for a potential wing support. At least, it could if someone didn’t know very much about anatomy, which includes most people.

The last two chapters deal with the publication of her work and her continuing research into other myths and legends. It ends with a reference back to expanding our search images to find the truth behind the stories.

The book ends with few nice addendums. There is a map of the world showing where things mentioned in the text were found. There is a page of suggestions for further reading, which include her other books, books for younger readers, and online resources. A combined glossary and index covers the more challenging and interesting words. The book wraps up with a page about Marc Aronson and how the book came about.

So to sum up, there is precious little dinosaur and a whole lot of griffin in this book. But it does a wonderful job of depicting a personal story about how dinosaurs have played a role in the development of our cultural beliefs. It also serves as a reminder that we should not dismiss stories as pure fantasy. Strip away the fantastical and you may find something real underneath.




You Don’t Know Darwinian Evolution (Or Maybe You Do)

Yesterday was Darwin’s birthday. So instead of trying to shoehorn some sort of Valentine’s Day themed post for the week or an article about Darwin and his life and the importance of evolutionary theory, I thought I would briefly discuss a few of the most common Darwinian myths I have heard. For most people, it seems, it is accurate to say You Don’t Know Darwin, or Evolution, or Darwinian Evolution.

1. I don’t believe in evolution.

Yes, you do. You just don’t know it because you’ve been lied to by people who don’t understand evolution either and are threatened by it. But before we get into that, let’s please dispense with the term “belief”. Belief requires faith with no evidence. Since there are mountain-loads of evidence for evolution, don’t believe in it. Accept the evidence all around you. Once you understand what evolution is, you will agree that you have to be brain damaged not to accept it is true. Here is the big secret. Here is the definition of evolution.

Change over time.

Let me hear you say it!

Change over time.

I can’t hear you!

Change Over Time!

That’s it. See? Not so painful. You’d have to be an idiot not to understand that things change. If nothing ever changed, we would have no history books and people could never complain about the “good old days” when students were better (yes, people have complained that today’s students are worse than the previous generation for literally over 3000 years, one can only assume that either the ancient Greeks were God-like brilliant or people are biased).

What’s that, you say? That’s not what evolution means? Well, yes, it really is. But you want to talk about biological evolution. Some people think that simply saying change over time is overly simplistic and doesn’t really describe biological evolution. Ok, then. Here is a better definition of biological evolution. Ready?

Descent with Modification

Seriously, that’s it. Children are different from their parents. Now, unless you are going to argue that you are exactly the same as your parents, that everyone is in fact a clone, you are an evolutionist. Congratulations.

Oh alright. You may have heard that individuals don’t evolve, only populations, or even species. What that means is that one does not evolve over the course of one’s own lifetime. For most organisms, that is true. Of course, if you are a plant, which has what is termed modular growth, that is not strictly true. Plants can reproduce through one of two methods. They can reproduce through seeds, or they can reproduce through vegetative growth. In vegetative growth, the plants can send out tendrils (many people might call such tendrils “roots”). Those tendrils can grow horizontally through the soil and then spring up to grow what appears to be a new plant. The new plant is often called a clone, thus some people refer to this as clonal growth. Cottonwoods and sumac are great examples of this, most of them you see are actually clones grown this way. I say clones, but that does not necessarily mean they are genetically identical. If a mutation occurs at some point in one of the cells in that root tip, it can get passed along through the continued growth of that root so that the clone is indeed slightly genetically different. Considering that some of these plants can grow vegetatively for thousands of years through thousands of “clones”, a fair bit of genetic diversity can occur from one end to the other. I mentioned earlier that this is called modular growth. It gets that name because mutations that occur at the root tips affect all growth after that point, but do not affect the part of the plant before that point. Different parts of the plant are effectively separated from each other genetically and, to a point, physiologically. This is why you can grow new plants from cuttings. If the plant didn’t have modular growth, you couldn’t do this. Just imagine cutting an arm off of a person and trying to grow a new body from the arm. Animals, like us, do not generally have modular growth (unless you are a starfish, or planaria, or…).

Bring in the clones!

Bring in the clones!

Many people prefer a definition of biological evolution that takes populations into account. Thus, you will find this definition in many places.

A change in gene frequency in a population over time.

In this definition, evolution is restricted to changes that affect the DNA throughout a population. Ok, fine. But what does that really mean to a nongeneticist? It means that populations change over time in a way that those changes can be passed on to offspring. This is different than, say, changes in height and weight through strictly dietary changes. Just because Americans eat more and are thus typically taller and fatter than people in most other countries does not mean we have evolved to be taller and fatter, it just means we eat too much. It shouldn’t take a genius to realize this is true. A great example of evolutionary change in humans is our wisdom teeth, otherwise known as our third molars. Does it make any sense to anyone that we were created with jaws too small to fit all of our teeth so that we wind up having to pull some out? No, that’s ridiculous. The reason that our jaws are shrinking is that we have switched from eating tough, raw foods to softer, cooked, and processed foods that are easier to digest and we no longer have to chew as much. Some people are now being born who never have wisdom teeth. Eventually no one will have wisdom teeth and orthodontists will be very sad as a good chunk of their income will be lost to evolution.

But what really defines a population? It should be clear by now that biology does not lend itself to neat little boxes. Biology is messy (if it stinks, it is probably chemistry, but that’s another discussion). Typically, a population is defined as a set of individuals capable of interbreeding. This is very much like the biological species concept (BSC). The difference is that a species can be divided into multiple populations because not every member of a species has access to every other member. If something gets in the way, you get separate populations of the same species. And here we have a problem. What is a species? Most people have heard about the BSC. Unfortunately, it doesn’t work for a lot of organisms. It doesn’t work for plants, who hybridize at the drop of a hat and can grow vegetatively anyway. It doesn’t work for bacteria, or parthenogenic species who only need females to reproduce, or animals that can be cut up like sponges and starfish and planaria, etc. The last time I counted, there were 26 different definitions of a species. The idea that a species is the only “natural” unit in taxonomy is a myth. Even species are not natural. Researchers use the definition that is most applicable to their research. For instance, paleontologists can’t possibly use the BSC. It is really hard to get fossils to breed. Some might even say impossible. As a result, paleontologists are stuck with what is called the morphospeces concept. If it looks sufficiently different, it’s a new species. This means of course that you can’t realistically compare modern and fossil species because they don’t mean the same thing.

This is a really long-winded way of saying that it is much better to talk about evolutionarily discrete lineages, rather than populations or species and why I prefer sticking with the “descent with modification” definition of biological evolution. If that seems harder to deal with, biology is messy. Get used to it. But just because it is messy doesn’t mean it’s wrong. Life is usually messy. Just ask any parent. If you want absolutes and certainty, go talk to a physicist. Biologists have to deal with the real world in all its chaotic mess. I envy physicists, I really do. They have it easy. Yes, physics is easy. Biology is hard.

Ok, that was a lot. But if you still say you don’t believe in evolution, you are deluding yourself. The other myths can be dealt with much more succinctly.

2. You have to be atheist to believe in evolution. Darwin was an atheist until he converted on his deathbed.

I hear that a lot, but seriously? Are you seriously going to sit there and tell me these guys are atheists? Ok, maybe the last one, but this is an issue of pitting one faith against another, so please pardon the joke.


The last three Popes.

"Your faith against his faith. Can you do that?"Count Barlow. Salem's Lot, by Stephen King.

“Your faith against his faith. Can you do that?”Count Barlow. Salem’s Lot, by Stephen King.

If you can’t trust that the Popes are devoutly religious, you have serious issues. But say you are one of those people that say the Popes may be religious, but they are going to Hell because they aren’t your sect of religion. Ok. Dr. Francis Collins is the head of the National Institute of Health. He led the Human Genome Project. He also happens to be an outspoken Evangelical Christian and has written extensively on why evolution does not conflict with Christianity. But Dr. Collins is a scientist, what does he know? What about Pat Robertson, leader of the 700 Club? Surely we can all agree that if Pat Robertson, of all people, does not think that evolution conflicts with Christianity, we can agree that you do not need to be an atheist to accept evolution.

Ok, you say that Pat Robertson is crazy. I won’t argue with you. But what about Billy Graham? If there is anyone more respected in the Evangelical Christian community, I don’t know them. Billy Graham has no problem with evolution. He is clearly not an atheist.

What about Darwin being an atheist? No, he wasn’t. He actually thought about going into the seminary to become a minister, but decided against it to pursue his academic interests. He didn’t seriously begin questioning his faith until his ten-year-old daughter died. After that, he lost faith in any sort of benevolent deity and he never recanted. The story that he converted to Christianity and denounced his views on evolution on his death bed is complete fiction. It was made up by someone who wasn’t even there. Why Lady Hope made up this story, I can’t say, but it is definitely a fraud. The important point here is that at no time did Darwin ever think that evolution conflicted with the Bible.

3. Evolution says that we evolved from monkeys, which can’t be true because A) I’m not a monkey, eww; and B) monkeys still exist.

Tell me, do most mothers die in childbirth? Then why would anyone think that a species has to go extinct when a new species arises? The reason that people think this is because they still have this view of the Great Chain of Being,” which was an old Christian view that everything had its place in the universal order. Rocks were at the bottom, then plants, then lowly animals, on up to humans being the most important mortal thing in all of Creation, topped only by the Heavenly Hosts, Jesus, and God Himself (that bit always confused me, if God is male, then there should be a female God, so where is She? Nevermind, I digress, that’s a whole other discussion.) Anyway, with this view in their head, people naturally assume that evolution works the same way. One species should naturally transform somehow into a new species.

How evolution works. Matt Bonnan.

How evolution works. Matt Bonnan.

Peripheral isolates. Taxon A is the original species. B-F are new species that evolved from the original species due to adaptation for the particular environments in that area. The original species is usually more of a generalist, able to survive in many environments.

Peripheral isolates. Taxon A is the original species. B-F are new species that evolved from the original species due to adaptation for the particular environments in that area. The original species is usually more of a generalist, able to survive in many environments.

Except it doesn’t work that way. Not all individuals of a species have to evolve together. If that species is divided into separate populations, or evolutionary discrete lineages, each population could evolve into a separate species. The original, or parent species, never has to change at all. Take the peripheral isolates concept. In this case, there is a species that has a broad range. At the edges of the range, members of the species find themselves in a different environment from the members of the species in the center of the range. The population exposed to the new environment will evolve in response to that environment, but the population in the center of the population never has to change. Thus, you have two or more species evolving from an original species that is still present.

But what about humans evolving from monkeys? No, that isn’t technically true either. Again, using the family analogy, let’s say your parents had siblings. Your aunts and uncles had kids of their own. You are related to your cousins through your parents. Pretty straightforward, right? Now replace everyone with species. You and all your cousins would be individual evolutionarily discrete lineages, you all have your own evolutionary path. Now, say that you represent all humans and your cousins represent all the species of monkeys. You aren’t a monkey, neither are your parents. your cousins, on the other hand, are (sorry, cuz). You (meaning all humans) share a common ancestor (your parents, or the ancestral species of humans) with your cousins (all the monkeys).

4. Evolution says that the earth is really, really old.

No, evolution has nothing to do with how old the earth is. The geologic time scale was actually put together by people correlating different rock units based on their relative position. Using the Law of Superposition, the oldest rocks were at the bottom, with the youngest rocks on top. Examining the rocks from place to place, they were able to line up different rock units into a long column. But it was all relative. They had no idea how old the rocks were. Finding the age of the earth didn’t happen until physicists discovered radioactivity. Some very smart physicists figured out that they could use the rate of radioactive decay to date rocks. All paleontologists and evolutionists did was say Thank You! So if you don’t like the age of the earth being over 4.5 billion years old, go talk to the physicists, it has nothing to do with evolution. Of course, when you do talk to them, you will have to deal with the fact that they have tested the theories quite well. We know they work because if they didn’t, we would not have nuclear bombs, nuclear power plants, x-ray machines, and a whole host of other things that work because of our understanding of radioactivity.

5. How does evolution explain the origin of life?

Easy, it doesn’t. Evolution only works on life that already exists. If you want to complain about the origins of life, go talk to a chemist. The origins of life is a chemical and physics problem, it has nothing to do with evolution.

5.Darwin invented evolution.

The last one for today might surprise people the most. Darwin did not invent, discover, or in any way introduce evolution. People knew that organisms change long before that. Joseph Buffon discussed the mutability (change) of species and that they had common ancestors in the 1700s. What Darwin did was provide a plausible mechanism for how evolution worked. Darwin provided evidence for natural selection. Of course, Darwinian evolution via natural selection is not the only mechanism. There is gene flow, which involves new material being introduced by immigrants into a population, and genetic drift, which is simple, boring, old random chance. But that is a topic for another day.

Myths and Misconceptions: The Great Chain of Being

I was talking with someone at an educator’s conference of all places that asked me how, if evolution was true, could monkeys still exist. Surely evolution meant that if we evolved from monkeys, that monkeys should no longer be around, right? This is a common misconception. I might even say it is the most common misconception I run across. It is so common, in fact, that paleontologists really get tired of hearing it because it means the person does not understand how evolution works at all. Matt Bonnan, a well respected paleontologist that mostly works on the giant, long-necked dinosaurs called sauropods, in a period of frustration, penned this cartoon. In it, he explains the first thing I ask people: Did your parents die when you were born? Did your parents become you? No, of course not, that’s silly. So why would you think that an entire species has to go extinct when a new one evolves?

bonnancartoonEvolution generally works the same way. Just as your parents and their siblings continued to exist after you were born (barring tragic occurrences of course), species seldom evolve all at the same time in the same way. There are almost always some populations of a species that do not noticeably evolve, at least, not in the same way. As a result, one can usually find populations of the parent species long after new species evolve. We see the same thing in TV shows. Just because CSI spun off CSI:New York and CSI: Miami, that did not mean the original show was cancelled. All three happily continued to air alongside each other.

Great Chain of Being Didacus Valades, Rhetorica Christiana, 1579

Great Chain of Being Didacus Valades, Rhetorica Christiana, 1579

This is pretty obvious when you think about it in other contexts. So why do people think evolution works differently? It all has to do with an old belief called the Great Chain of Being. While it had its origins as early as Aristotle’s Scala Naturae, it reached its heyday in the medieval Catholic Church. This chain organized all of existence into a hierarchical system with rocks and minerals at the bottom and God at the top. Some of them got very detailed, even putting different minerals in order. Of course, all of them had humans as the pinnacle of earthly creation, with the nobility and kings above all as the highest order of Man. This type of classification still holds sway to this very day for many people for a very powerful reason.

For people with a hierarchical worldview, this is very appealing. Everything has its place and the Great Chain of Being strictly lays out who has authority over who. It is neat, tidy, and ordered. It also feeds into normal human desire to feel special. It enshrines human exceptionalism into the very soul of the worldview.

And this is where people run into a brick wall with evolution. Evolution tears apart this neat, ordered hierarchy. Life becomes messy, without clear boundaries and order. Most importantly, evolution, as they see it, makes no distinction between humans and the rest of the system of life. It puts humans as just another branch on the great family tree, with nothing inherently special putting humans on top and that simply will not do. I do not mean for this to be taken as derogatory of any particular religious belief or religion in general. The need for order and security and to feel important and with a purpose are understandable human desires with a rational basis at their core that we all feel to some extent. Unfortunately, when applied to natural history, all available evidence indicates it is wrong.

So if evolution does not work this way, how then does it work? How should evolutionary lineages be considered and how do species evolve? Let’s tackle the latter question first and then see how it looks on a grander scale.

There are many ways organisms can create new species, or speciate. But there are two main patterns. One is similar to the incorrect view of evolution shown above, in which a species gradually evolves into another species as a unit due to changing environmental conditions, such that the original species and the new species are only in existence together for a brief transitional period. This is called “anagenesis”. This sort of speciation has been proposed most commonly in groups like ammonoids (Mesozoic shelled squid-like creatures) and foraminifera (a large part of plankton in the oceans). On a side note, this sort of speciation plays havoc with interpreting the fossil record because it creates what is known as “pseudoextinctions”, in which the original species appears to have gone extinct when in reality it just changed.anagenesis

The other pattern, and the one that is considered far more common,  is called “cladogenesis.” In this case, different populations of the same species evolve into two or more species. Much of the time, populations of the original species stick around and can do so indefinitely, so long as the environment allows.

There are several ways cladogenesis can happen. Most commonly, populations get separated by some sort of barrier, like a river or mountain, possibly a volcano. It can be anything, so long as it prevents breeding and thus gene flow between the populations. This can even happen if populations diverge from each other by specializing in different parts of the same area. Probably the most famous examples of this are the cichlid fish in Africa. They have formed numerous species by specializing in different microhabitats within the same geographic area.

Taxon A is the original generalist species. B-F are new species evolving at the edges of the original range.

Taxon A is the original generalist species. B-F are new species evolving at the edges of the original range.

Another way cladogenesis can occur is by what is known as “peripheral isolates”. In this situation, you have a generalist species that has a wide range due to its ability to fit into multiple niches. However, subpopulations can evolve to specialize into the different niches to the point they no longer breed with the main ancestral species. This form of cladogenesis is very similar to the ones listed above. In a way, it can be considered a combination of them, with subpopulations adapting in different geographic areas.

The important point in all this cladogenesis talk is that at no time is it ever required that the original species go extinct. They can and often do at some point, but cladogenesis does not involve a species changing into another, it involves a species splitting up into multiple species. Much like parents are free to live their own lives once the children leave the nest (and even while the kids are still at home), once a species splits, each new species follows its own evolutionary path that is separate from the original species. In short, there is no linear chain of species going from one to the next.

So what does this look like over geologic time? It looks something like a branching tree (or, if it happens over a short time, like a bush). The ancestral species forms the trunk at the bottom and each branch represents another split, until finally, you reach modern day, represented by the leaves.

McFadden, Bruce. 2005. “Fossil Horses – Evidence of Evolution.” Science Vol. 307. no. 5716, pp. 1728 – 1730

McFadden, Bruce. 2005. “Fossil Horses – Evidence of Evolution.” Science Vol. 307. no. 5716, pp. 1728 – 1730

It is often argued that this does not get rid of the line of species from distant ancestor to descendant. If you look at the family tree of horses, for example, you can still draw a line straight from Hyracotherium all the way to the modern Equus. It is true, you can. However, it is not a straight line. It proceeds in fits and starts, with many branches, most of which die off. It follows environmental changes and interactions with other organisms. Here is the big kicker though. All the species sharing a common ancestor that survive at any given point of time have all evolved equally. It may not be apparent, some species may show far more changes than others, but all of them have experienced the same evolutionary time. There is no hierarchy of dominance in evolutionary terms. Every bacteria has experienced the same amount of evolutionary time as the lineage that led to humans. One can draw a straight line from a root of a tree to any leaf, but one would be hard-pressed to claim that single leaf is more important than any other leaf. So if you are looking for a reason to support human superiority, evolution will not help you. As a result, evolution can be a serious blow to the human id.

To those people who have problems with evolution on this basis, I ask you to consider that simply because bacteria have experienced the same time for evolution, that does not diminish human accomplishments. We have built communities that span the globe, we have explored the edges of the solar system and beyond. We have accumulated vast stores of knowledge that we have preserved for our descendants. We have glimpsed the inner workings of life itself. We have witnessed the awe-inspiring glories of the universe. If you need something to take pride in humanity, do not look to our evolutionary heritage, look to what we have achieved that is unmatched (as far as we know) by any other organism. As we so often tell our children, it is not where we came from that determines our worth, it is who we make ourselves to be.

Myths and Misconceptions: The Transition From Water To Land Is Ridiculously Hard

It is commonplace to hear people say they do not accept evolution because they don’t see how some of the changes could have taken place. It’s just too complicated they say. What use is half a wing, they ask. As it turns out, the usefulness of half a wing, even a featherless baby wing, has been demonstrated, so that argument is out. Another transition people have difficulty with is the transition from water to land. Regardless of the fact that we have a good bit of fossil evidence demonstrating the transition, many people think that fins and feet are so radically different that they don’t see how it could have happened. Recent research has demonstrated in several ways that this transition is not nearly as hard as people might think, which may explain why it has happened multiple times in the history of life. For a truly bizarre history, one can look at the evolution of the elephants. Before they were elephants, they went from water to land back to the water, then back to the land.

Tetrapod phylogeny from The Tangled Bank, by Carl Zimmer

Tetrapod phylogeny showing a few of the important fossils from The Tangled Bank, by Carl Zimmer

So what tells us it really isn’t that hard? Let me introduce you to the robot salamander. This robot and its predecessors were designed to test different models of neural circuits involved in locomotion. What they found is that the same movements of the limb and torso allowed both swimming and walking. The only difference was the amount of resistance placed on the feet. Obviously, the ground supplied much more resistance to the limb motion than did the water. This caused a change in the neural signal, causing it to slow down and become stronger to account for the change in muscle power needed and the reduced speed of the movement. It was the same signal from the brain, it activated the same motor pathways. In other words, fish already had the neural pathways to be good salamanders.

Still, there are all the changes needed in the musculature and bones that surely had to be problematic. Research that has only recently been published indicates this isn’t hard either. Bichirs are a type of fish that regularly flops about on land and has true lungs. Emily Standen wanted to see what would happen if a bichir was raised on land and not free-swimming in the water. What they found was that the bichir changed how they crawled about, adopting a pattern that was more efficient. They held their heads higher off the ground and brought their fins closer to the body. More than simple behavioral changes, their skeletons changed as well. The supporting their pectoral fins changed subtly in ways that bore similarities with fossil of the earliest “fishapods”. It should also be noted that these experiments were on juvenile bichirs who were less than 70 days old and only lasted for eight months. This is not a lot of time to see differences.

I want to be clear that the bichir experiments do not show evolution of the fish. Evolution does not occur within a single individual. What we see here are epigenetic changes, not involving changes in the DNA. Epigenetic changes demonstrate developmental plasticity, the range over which a species can adapt to new environments without needing genetic alterations. But we now know that epigenetic changes can be passed on to the next generation in processes that are still only dimly understood. Unless these changes become incorporated into the DNA, they will fade if taken out of the environment that is producing the selection for that change. But eventually, these sorts of epigenetic changes can lead to real DNA changes that will lock in the change for all further descendants. In other words, what these experiments demonstrate is that fish already had the necessary developmental plasticity to evolve adaptations to land.

A rather extreme version of syndactyly. PMID: 21273726

A rather extreme version of syndactyly. PMID: 21273726

As I stated, these sorts of changes have to be incorporated into the DNA, but surely that requires a lot of changes? There have to be a lot of genes that have to be changed radically, right? Turns out, no. The switch is rather simple and it doesn’t even involve changes to protein-producing genes. All it takes is a change in the regulation of those genes. Change the developmental timing, change the amount of a protein here or there, and you turn a fin into a limb. Fish and terrestrial animals use exactly the same genes to make fins and limbs. They just change how they use them. This is why you occasionally get people born with webbed hands and feet. It can even cause polydactyly, having more than the normal number of fingers or toes.

Left column shows the control animals showing normal fins. The right column shows the bichir raised on land. Standen et al. 2014.

Left column shows the control animals showing normal fins. The right column shows the bichir raised on land. Standen et al. 2014.

A study published in 2012 looked at the regulation of hox genes, the genes involved in controlling the shape of our bodies, how our limbs are made, how many fingers we have, that sort of thing. All animals have them, they just vary in how many and how they are used. Renata Freitas and her associates took the control sequence for Hoxd13 from a mouse and put it into a zebrafish. The only thing this did was cause the Hoxd13 gene to be overexpressed. This caused the fish to have reduced fin tissue and the growth of cartilage forming what can best be described as a rudimentary limb. Just for emphasis, let’s say that again, simply changing the amount of protein created from this one gene turned a fin into a rudimentary limb. In other words, fish already had all the genes needed to make limbs for terrestrial locomotion.

So, we’ve seen that we have a lot of fossils documenting the shift from water to land. We’ve seen that fish already had the needed neural wiring to walk, the developmental plasticity to get started, and all the genes necessary. You can even see the transition showing up in the nerves that supply the human arm called the brachial plexus, the bane of medical students everywhere, which seems bizarre and nonsensical, until one looks at it from an evolutionary perspective. Then it all makes sense. But that is a topic for another day. All the transition really took was a prolonged stimulus that provided a selective advantage for walking around and limbs developed naturally from what was already pre-existing and working fine in the environment in which they evolved. Amazing how much change can be accomplished simply by a change in venue and a little push in the right direction.

Fossil Friday, Going Swimmingly

No one guessed what the fossil for this week was. Take a look at the image below and see if you can figure out who this vertebra belongs to before continuing on after the image. As you may have deduced from the title of the post, it is an aquatic animal.


This is not the lizard you're looking for. Platecarpus. Wikimedia.

This is not the lizard you’re looking for.Platecarpus. Wikimedia.

This fossil is a really nice dorsal vertebra of a giant marine reptile. Most of the ones usually found in Arkansas are mosasaurs, but this one is different. It lived at the same time as the mosasaurs, placing it in the Late Cretaceous Period. As with all other Late Cretaceous fossils in Arkansas, it was found in the southwest corner. Specifically, it was found near Saratoga, Arkansas in Howard County by local resident Matt Smith. Interestingly, the very same spot has also turned up several nice mosasaur fossils, so it was a popular place in the Cretaceous seas. It shouldn’t be too surprising though, as it was a nearshore environment in a tropical climate much like the Bahamas today, so there would have been lots of good eating for hungry marine predators.



Ok, enough of the teasing. The vertebra we have here is that of a plesiosaur known as Elasmosaurus. These are classic marine reptiles that most people are familiar with to some degree. They have sometimes been described as looking like a snake that swallowed a sea turtle because of the relatively wide bodies with oar-like flippers and a very long neck. They are thought to have spent much of their time slowly cruising the seaways, using their long necks to catch fish unawares. some people have even suggestd that they floated at the surface of the water with their head out of the water, so that fish could not see it, allowing them to plunge their head down into the water and catch fish from above. That is pure speculation though. Right now there is no way to really test such hypotheses, so feeding methods remain in the realm of speculation until such time as someone figures out a way to test it adequately. At the moment, biomechanical tests indicate that either method would have been possible.

Mosasaur vertebrae. Note the rounded left end.

Mosasaur vertebrae. Note the rounded left end.

So if you find a vertebra like this, how do you tell whether it is a mosasaur or plesiosaur vertebra? They can both be large, although the one pictured here is the largest one I have ever seen found in Arkansas. The best way to tell is to look at the ends of the centrum, otherwise known as the body of the vertebra. Most of the time, that is all that is preserved, as all the processes that stick out have been broken off, like we see in this one. Plesiosaur vertebra have flat, possibly even slightly concave, or indented ends. Mosasaurs, on the other hand, have what is known as procoelous vertebrae, which have one end convex, a bit more rounded off. These differences make mosasaur vertebrae look more like over-sized lizard or croc vertebrae, whereas plesiosaur vertebebrae look more like the disc-like vertebrae seen in fish. This may mean that plesiosaurs were more adapted for aquatic life than mosasaurs. Both were clearly fully aquatic, what with neithr one of them having legs of any sort, but plesiosaurs appear to have been aquatic for longer, giving their spine to more fully adapt.


Indeed, when we look at the age of the rocks their fossils have been found, mosasaurs are restricted to the late Cretaceous, whereas the plesiosaurs first appeared all the way back in the Triassic (another successful prediction based on evolutionary theory). This means plesiosaurs had well over 100 million years advance on the mosasaurs. It didn’t really help them in the end though. About the time mosasaurs appeared, plesiosaurs were declining. Mosasaurs evolved and spread quickly, becoming the dominant marine predator of the Latest Cretaceous. Does this mean that mosasaurs outcompeted the plesiosaurs? Not necessarily. It has not yet been sufficiently determined whether or not mosasaurs simply filled a niche left open by the plesiosaur decline or competitively excluded them. there is also the argument to be made that they would not have competed at all. The body shapes of mosasaurs and plesiosaurs are quite different, indicating they filled different niches in the marine realm, so they weren’t going after the same food sources. Therefore, there is no particular reason we know of that they could not have existed alongside each other without adversely affecting each other.




Nessie picture collection by Darren Naish, Tetrapod Zoology, July, 2013.

Most people are familiar with them due to the much discussed “Loch Ness Monster”, which has often been said to be a supposed plesiosaur that has somehow survived for 70 million years. Of course, that idea doesn’t make a lot of sense for several reasons. It is highly unlikely that plesiosaurs could have lived for so long without leaving any trace of a fossil record. It does happen occasionally though. The coelacanth is a famous example of that, for a long time having a good 65 million year gap in their fossil record. They were thought to have gone extinct along with the dinosaurs until living specimens were caught. We know more about them now and their fossil record is no longer quite as limited as it once was, but it still has wide gaps in the fossil record. But more serious problems for Nessie arise from the fact that plesiosaurs were large, air-breathing marine reptiles. Coelacanths went unnoticed because they moved to the bottom of the sea, an option not available to plesiosaurs, which were limited to surface waters, and relatively shallow waters at that. That means they lived in exactly the sort of marine environments most visited by humans. That makes it hard for them to hide from people today and puts their bones in prime spots in the past to fossilize. Then of course, there is the problem that Loch Ness is a freshwater lake and plesiosaurs were adapted for saltwater. Not to say a species couldn’t have adapted for freshwater, but it does make it less likely. Finally, there would have to be enough plesiosaurs big enough to support a breeding population and there is simply no way they could all hide within the confines of a lake, especially since they have to live at the surface much of the time.

baskingsharkdecompBut what about the supposed bodies that have been found of plesiosaurs? They have all been identified as decomposing backing sharks. Basking sharks are one of the largest sharks known today. they are pretty harmless though, as they are filter feeders, much like the whale shark. When their bodies decompose, the jaws typically fall off pretty quickly. So what has been identified as the head of a “plesiosaur” was actually just the remaining portions of the cartilaginous skull without the large jaws. If you look at the picture of the asking shark here, there isn’t much left after you remove the jaws.


Next week is Labor Day on Monday, so I will likely not post a new fossil next week. I will post something next week, just not a mystery fossil. But there will definitely be one the following week, so please come back to see the next fossil and see if you can guess what it is before Friday. In the meantime, enjoy your vacation.

Website Review and the Misconception of a Theory

In a quick review, I would like to discuss the website by Lin and Don Donn,

This website is part of a much larger website that is filled with a lot of information on all sorts of history. As Mr. Donn states, they do not claim to be experts in anything, so do not claim everything on the site is correct, although they do try. It is clear they have put a great deal of time and effort into making a substantial site with the honest intention of providing accurate and useful information to teachers. They have won awards for an impressive site. However, in the evolution of humans, they seriously fall down.

The early humans website has several links to good resources. Unfortunately, it has two things that destroy the science educational credibility of the site completely. The first is a link to a presentation teaching Biblical creationism, a subject that has no place in a public school as it is both scientifically invalid and pushes one specific religious view, which is illegal in the United States. Regardless of whether one believes in creationism or not, it is not legal to teach a specific religion in public schools and it is especially not valid to teach that religious view in a science class. The only way to make this legal would be to teach the creationism stories of every other religion equally, without comment as to which one the teacher believed, which would be impossible. Even then, it would have to be in a religious studies class, not a science class. If we are to preserve everyone’s First Amendment rights to freedom of religion, we simply cannot have government-run public schools teach one religious view and we certainly cannot teach that view as a scientifically valid theory. I am hitting this point especially hard because it is a serious point of controversy in the United States, but it should not be. Keeping creationism out of the schools is not an attempt to suppress anyone’s views. It is an attempt to preserve everyone’s right to make their own religious choices without government interference.

That leads me into the second problem, one which is stated boldly right up front. One of the big problems we have in science literacy is that many people do not understand the difference between the colloquial use of the term “theory” and the scientific meaning of the term. To quote the website: “A theory is a guess based on some facts.  Remember a theory is not proven.  One of the great controversies of our time has been the theory of evolution.” This is massively wrong in two areas.

The term they have defined is NOT a theory. What they defined was SPECULATION. Anyone can come up with an idea, but that does not make it a scientific theory. First, one must have a hypothesis, which is a testable idea, based on observation, that explains a relationship between two or more measurable things. There are two critical parts to this. The observations, so it must be an attempt to explain something we actually see in the real world. Second, that explanation must be testable. If there is no conceivable way to test it, the idea remains in the realm of speculation and can never be taken as a scientific theory, or even a valid hypothesis.


Great hypothesis, but not the way to do science.

Once one has a series of hypotheses that have been tested by many people, none of whom have been able to disprove the hypotheses, one can formulate a scientific theory. That theory ties the hypotheses together, explaining numerous detailed observations into an explanatory framework that applies broadly. An example of this is the Theory of Gravity. Numerous observations were made showing gravity exists, there is no doubt about that. Many observations showed precisely how it worked and the relationship of different masses to each other, both on earth and in the universe as a whole. However, to make a theory, we needed more than these observations, we needed a way to accurately describe and predict these relationships. Isaac Newton discovered a mathematical equation that could be used to predict the motions of the planets. That equation was then tested many times and found to be valid everywhere, at least at the speeds attained by most things in the universe. Einstein went further with his Theory of Relativity, which extended our understanding of gravity into realms beyond the experience of everyday existence. Even here, these started out as hypotheses, requiring many people to test over and over gain. Not only has no one been able to prove them wrong, but no one has come up with an explanation that better fits the data. Therein lies the key, testing and testing and basing the acceptance of the theory on data, evidence that either supports or disproves the theory. Without that, it is not a theory.


As such, there is no Law of Gravity. We know it exists, it is fact that is undeniable. The Theory of Gravity provides a framework in which gravity works that has been put to the test. In a similar fashion, there is no Law of Evolution. We know it exists, it is a fact that is undeniable. Why? Because the idea that biological life forms change over time is something that cannot be argued against. All one has to do is acknowledge we are not clones of our parents, or look at the diversity of changes brought about by dog and cat breeders, sheep and cow breeders. We see biological change all around us. Evolution is therefore a fact, just like gravity. The Theory of Evolution put forth by Darwin is more properly called the Theory of Natural Selection, which explained this change through the aforementioned natural selection. It has been tested numerous times and shown to work. Is natural selection the only way in which species change? No, but it is a major mechanism. But the point here is that it has been tested and retested. Like all scientific theories, it is not simply a guess based on a few facts. It is permissible to argue about specific mechanisms, but trying to argue whether or not evolution occurs is like arguing whether or not the earth is flat or that we need air to survive.

Evolution and Gravity are Theories (Humor)

Questions from the Bill Nye/Ken Ham debate on creationism

Bill Nye the Science Guy debated Ken Ham, a young earth creationist who runs Answers in Genesis and the Creation Museum, Tuesday at the Creation Museum in Kentucky. The question they debated was “Is creation a viable model of origins in today’s modern, scientific era?” I won’t get into the debate itself, you can watch the debate in many places, such as here and here and decide for yourself who won or lost and whether or not they presented convincing arguments. What I do want to get into here is an article I saw called “22 messages from creationists to people who believe in evolution.” It illustrates why paleoaerie was created in the first place. When I read these statements from creationists, the lack of comprehension of really basic science concepts was highly discouraging. This isn’t even just about evolution, it’s about basic science understanding and logical thought processes. If one doesn’t even understand what a theory is, how can that person be expected to make a rational decision about anything? Life becomes nothing more than random guesses. We are blind men in a watch tower. “Blinken! What are you doing up there?” “Guessing? I guess there’s no one coming.” That’s no way to run your life, much less the whole of society.

So I thought I would provide at least some sort of answer to these questions. Many of them are questions that are quite commonly raised, so it is worth at least attempting to answer them. The first thing to address, though, is the title of the article itself. Scientists do not “believe” in evolution. It is not a religion or ethical/moral code. Scientists accept evolution because of the staggeringly huge amounts of evidence that supports the theory, not because some scientific leader told them they must believe it or go to science hell.

1. Bill Nye, are you influencing the minds of children in a positive way?

I’m not Bill Nye, but for me, I would say yes. Any attempt to teach children how to think rationally, to question how the world works and to use evidence to attempt to answer those questions, is a positive influence. Teaching children to obey and believe simply because they are told to without question is a bad influence. That is how horrific atrocities are committed and accepted by a blind populace. Every great discovery, invention, or acheivement came about because someone asked a question (more likely several questions) and trying to figure out the answer beyond just accepting what they were told. The bow and arrow, agriculture, medicine, computers, basic housing, nothing man-made would exist if we never asked questions and strived for answers. Creationism the way Ken Ham and others formulate it, is telling people to NOT ask questions, the only answer you need is “God did it.” That sort of thinking not only denies the reality of our shared experiences, but dooms civilization to failure and would have kept us in the trees. We would never even have made it to the caves. That is why this is important.

2. Are you scared of a Divine Creator?

There are two (more than that actually, but two is what I am sticking with here) ways to answer that question. If one starts with an atheist point of view, one cannot truly be afraid of something you don’t believe exists. But this question falsely assumes that evolution and religion are mutually incompatible, that one cannot believe in evolution and a Divine Creator at the same time. This is wrong. Pope Benedict stated that evolution is true, even calling the idea they are incompatible an absurdity. Pope Pius XII endorsed evolution, as did Pope Paul II, and Pope John Paul II called evolution “an effectively proven fact.” Surely no one could call these leaders godless or lacking in Christian religion. Billy Graham, an influential Baptist Evangelical leader, was not opposed to evolution. Pat Robertson, leader of the 700 Club, has called Creationism a joke and that a 6,000 year old earth is ridiculous. He has no problems with theistic evolution, only nontheistic evolution. In other words, he accepts in God-guided evolution. Truth be told, there is NOTHING in evolutionary theory that denies God. God is not a necessary part of the theory, but it does not claim God did not guide it. Francis Collins, Director of the National Institute for Health, is well known to be a devout religious man, yet also firmly accepts evolution.

3. Is it completely illogical that the earth was created mature, i.e. trees created with rings…Adam created as an adult…?

Yes. I think it is illogical. For that to be true, you have to admit that God is intentionally lying to you. Why would God create an earth that gave all appearances of being much older if God did not expect you to accept the evidence God provided? Is it logical to assume God lies to you? If so, why would you worship a God that is a liar?

4. Does not the Second Law of Thermodynamics disprove evolution?

No. The Second Law of Thermodynamics states that 1. Heat will not flow from a cold object to a hot object. 2. Any system which is free of external influences becomes more disordered with time, which can be expressed as entropy. 3. You cannot create a heat engine which is 100% efficient in converting heat to useful work. For example, a (working) refrigerator is clearly colder on the inside than on the outside. It maintains this temperature by pulling heat from the inside and dumping it outside. One might say that this violates the 2nd law, but it doesn’t because it uses the fact that pressure and temperature are intertwined. It pumps a coolant that absorbs heat from the interior, thereby becoming less dense. It then takes that coolant and compresses it, releasing the heat so the coolant than then start the cycle over again. This requires energy to do this. The refrigerator uses electricity to add energy into the system, which is lost through this process. Overall, the entropy goes up, despite the refrigerator becoming less entropic on the inside, that disorder is simply moved outside. In the same way, the earth is collects a vast amount of energy from the sun. That energy is absorbed by plants, which then gets (very inefficiently) converted to work energy by themselves and everything that eats them. Overall, the process is extremely inefficient. Without the sun, no life could exist on earth, entropy could not be fought. But the sun supplies so much energy, it is simplicity itself to create order in some areas even while disorder of the whole increases.

5. How do you explain a sunset if there is no God?

Disregarding the spelling mistake (English teachers, where are you?), this question doesn’t even make sense. Sunsets happen because the earth rotates on its axis. Stand in front of a light with a little Lego person on your forehead and turn around. That Lego person on your forehead will experience a “sunset” for every revolution you make. Now imagine that process as you standing on the earth and the light being the sun.

6. If the Big Band is true and as taught as science along with evolution, why do the laws of thermodynamics debunk said theories?

They don’t. See above. Both evolution and the Big Bang Theory are formulated with the laws of thermodynamics in mind and are fully compatible with them. If they weren’t, no scientist would take them seriously. They are, so we do.

7. What about Noetics?

To be honest, I’ve never heard of Noetics. One minute while I perform Google-fu…According to Wikipedia, “noetics is a branch of metaphysical philosophy concerned with the study of mind and intellect. Noetic topics include the doctrine of the agent/patient intellect (AristotleAverroes)[1] and the doctrine of the Divine Intellect.”  What about it? This has nothing to do with evolution. If you are asking where consciousness comes from, one first has to define what you mean, as there is no universally accepted definition. However you define (presuming one is using a rational definition), humans are hardly unique in being “conscious”. The idea that we are the only animal that is conscious is simply a conceit to make us feel special. There are gradients of consciousness exhibited by a wide range of animals that are not human. Therefore, it seems to have evolved. If one is talking about the idea that you can know the universe simply via self-examination, there is abundant evidence that shows just how fallible human perception is. There are entire fields of study devoted to the topic. It is how magicians perform their craft, why marketers are so successful. As helpful, beneficial, and worthwhile it is, self-examination without reference to the outside world cannot even accurately teach you about yourself, much less the universe.

8. Where do you derive objective meaning in life?

Again, this has nothing to do with evolution. Meaning in life is a personal decision, not an objective part of the universe. The meaning of life is what you make of it. Thus, an objective meaning of life is a non sequitor as it is subjective by definition.

9. If God did not create everything, how did the first single-celled organism originate? By chance?

Yes. There are a lot of hypotheses about how that happened, but we don’t honestly know. At any rate, the question has nothing to do with evolution. Evolution does not deal with the origin of life, only what happened to it after it was here. If you want to understand the physical processes that led to the origin of life, I suggest you talk to a biochemist and biophysicist. That is in their bailiwick, not in evolutionary theory. But let’s ask that question in a different way. If God created everything, how did God get created? Did He create himself? And sorry, but the answer of “He always existed” is simply a copout. The other problem with this question is the assumption that there are only two possible mutually exclusive answers, that it is either evolution or God. What if it were aliens? No, I’m not seriously suggesting that, if for no other reason than it only pushes the question back to where the aliens come from and so answers nothing. I am simply saying that other possibilities exist. They are also not mutually exclusive. You can accept evolution AND God if you wish. You may as well ask how can a pilot fly if he didn’t invent airplanes. One is not dependent on the other, nor does one being true rule out the other.

10. I believe in the Big Bang Theory…God said it and BANG it happened.

That’s not a question, just a statement of opinion. It also has the serious flaw in that it indicates the person refused to even consider the question, going on nothing more than blind faith. That’s ok in a religion, but is a horrendous failure in science. That sort of thinking also fails the reality test, in that reality does not care what you believe. You may believe you can fly and jump off a tall building, but unless you have brought along a parachute or hang glider or some such object, the ground will still kill you. Personally, I would rather someone tested the parachute before I staked my life on it.

11. Why do evolutionists/secularists/huminists/non-God believing people reject the idea of their being a creator God but embrace the concept of intelligent design from aliens or other extra-terrestrial sources?

First off, English teachers, help this man. Second, almost no one does, so this question makes no sense. It lumps a whole lot of people into a very strange category. Most people who “embrace the concept of intelligent design from aliens” are generally considered whackjobs and not taken seriously, so it both has nothing to do with evolution and everything to do with a very incorrect view of people who accept evolution. The accepted scientific thinking on life originating from aliens is that there is no proof or any real evidence for that idea, so it is not considered at all scientific and is therefore unaccepted. There are a few people that support the idea, but as far as I know, no one, not even them, really consider it a scientifically supported hypothesis.

12. There is no inbetween…the only one found has been Lucy and there are only a few pieces ot the hundreds necessary for an “official proof.”

First off, there is no “official proof” of anything in science. There is either evidence supporting it or not supporting it. Secondly, there are far more fossils than of just Lucy. There are multiple species of Australipithecus, as well as Ardipithicus, Sahelopithicus, Paranthropus, Homo habilis, Homo erectus, Homo neanderthalensis, etc. May I suggest you spend some time perusing the Smithsonian site on human origins? They have quite a nice discussion of human origins and present far more than just Lucy.

13. Does metamorphosis help support evolution?

Yes, it does. Careful study of how different animals undergo metamorphosis has helped to elucidate the relationships between a large number of different animals. The study of amphibian and insect relationships requires a detailed examination of how those processes play out and they have been exceedingly helpful in understanding the evolutionary pathways in these groups. There are still plenty of unanswered questions, but that is why we do research, to try to answer those questions. Moreover, research on those topics is an important part of medical research on regeneration, in the hope that if we can fully understand it in other animals, we may be able to bring that knowledge to bear on helping humans do it to, so that we may one day grow back lost limbs and organs and not have to depend on prosthetics.

14.If evolution is a theory (like creationism or the Bible) why then is evolution taught as fact?

If evolution were indeed a theory like creationism, it would not be taught as fact, it wouldn’t be taught at all because it would be only fit for a religion class. But it is a theory in the same way that gravity is a theory. There is no law of gravity, there is a Theory of Gravity that explains the mathematical relationships and how it works in the universe. A scientific theory is not simply a guess. It is a scientific concept that explains a large array of observable facts, a concept that has been tested and retested and tested again by lots and lots of people. Scientific theories are constantly being revisited to see if new observations still support it. The simple fact of the matter is that no one has been able to provide any better hypothesis that explains the observable data. Sorry, but “God did it” is not a verifiable hypothesis. One cannot even proof or disprove God exists, God is a concept that falls outside of science. If someone can come up with a way to either proof God exists that can be objectively tested or can come up with a better hypothesis that disproves evolution, again, with objective, verifiable facts, they would become famous and would win the Nobel Prize. That hasn’t happened, so until it does, we will stick with evolution.

This question not only misunderstands what a scientific theory is, but it misunderstand what the theory of evolution is. Here then is the essence of evolutionary theory: everything changes. Specifically, living organisms change. Even more specifically, we can observe those changes in the genetic distributions within populations. If we see genetic changes in populations, we have proven evolution happens. Basically, if you can agree that you are not a clone of your parents, you accept evolution. That is why we teach evolution as a fact, because it is.

15. Because science by definition is a “theory” – not testable, observable, nor repeatable, why do you object to creationism or intelligent design being taught in school?

Because science by definition is none of those things. To be considered science, it must be testable, observable, and repeatable (at least in some aspect). Thus, a dinosaur bone is not science. It is a fact. It exists. That it is a dinosaur and that a dinosaur means a specific thing is science because it is a testable concept. Other people can take that definition of what a dinosaur is and make their own observations to test it. They can make predictions and then see if those predictions hold up. If it can’t do this, it’s not science. Something that is not testable, observable, nor repeatable is called speculation or religion, but most emphatically NOT science. That is why we resist creationism or intelligent design being taught. They have no evidence to support them, they have no testable predictions that would support the ideas and what few predictions they have made have been proven wrong. Therefore, they have nothing to do with science and should not be taught as science. If they are going to be taught in school, it should be limited to a religion class. Even then, that religion class, to be allowable in a public school, would also have to teach equally other religions. So unless you are willing to have Islam, Judaism, Shintoism, Buddhism, Satanism, and any other religion taught on an equal footing, you can’t have them in a public school that is bound by law to not advocate any single religion over another. To do so violates our most fundamental right, freedom of religion.

16.What mechanism has science discovered that evidences an increase of genetic information seen in any genetic mutation or evolutionary process.

Dzo, fertile crossbreeds of cows and yaks. Wikipedia.

Dzo, fertile crossbreeds of cows and yaks. Wikipedia.

There are actually several processes. It would take several books to adequately answer that question, so I will just mention a few in brief. Genes get accidentally duplicated all the time, our genomes are filled with duplicated genes. Most genes we have are in fact part of gene “families” which originated from the duplication of an earlier gene. When this happens, the duplicated gene is then free to evolve into something else. The original gene is still constrained by its original function, so it has a limited ability to change without breaking. However, that spare gene can change independently and it doesn’t matter if it can no longer perform its original function. It then has the ability to over time pick up a new function. Another way to increase genetic information is through viral infections. Our genome is about 8% viral origins. Viruses function by inserting themselves into the genome of their host and using the host cell to make the viral proteins. When the virus copies itself and spreads to other cells, it very often takes a small part of the host genome with it. Also, quite often, a virus gets inserted into a host genome, but loses its ability to replicate itself, thereby getting trapped in the host cell. If that cell happens to be a reproductive cell, which happens, it will get passes on to offspring as a permanent part of the genome. This is in fact virtually the entire basis of the field of gene therapy. Another way is good old fashioned sex. Hybridizations occur between closely related species all the time. Most of the time, those hybrids are sports, they can’t reproduce, but sometimes they can. Red wolves and Gray oaks are great examples of species that have been created through hybridizations. Plants are the ultimate masters of hybridization. They hybridize and create new species at the drop of a hat. They also readily duplicate their entire genomes. Of course, bacteria and many prokaryotes regularly swap genes among each other in a process called conjugation. There are many other ways, this is just the tip of the ice berg, but I hope I have demonstrated that increasing genetic information is really quite easy and happens all the time.

17. What purpose do you think you are here for if you do not believe in salvation?

Again, another question that has nothing to do with evolution. How does this even relate to the topic? The other flaw in this question is that it assumes we all have a purpose at all. What evidence can you give me that anyone has a purpose? What evidence can you give me that you can know the mind of God well enough to know what that purpose is? What is the purpose of a baby that dies at birth? What is the purpose of a person that never has children? Why do we need a purpose? Each of us are here because our parents had unprotected sex. There is no requirement that it be any deeper than that. It is fine to ask that question, but honestly, what does that have to do with science or evolution? For me, I think our purpose is what we choose to make it. Only you can answer what your purpose is and only if you decide to create one for yourself. As far as Salvation goes, why do we need to believe in Salvation? Why do we need Salvation? For us to need Salvation, that requires that God made us imperfectly so that we need to be saved. Why would God create something that needed God to rescue it? What need did God have to create something who’s only purpose was to worship God and ask to be rescued? These are not scientific questions. They are religious, philosophical questions. They are by their very nature outside the realm of science, at least, until someone comes up with a way to objectively test them. But they most certainly do not have anything to do with whether or not evolution occurs.

18. Why have we found only 1 of “Lucy”, when we have found more than 1 of everything else?

See question 12 for “Lucy”. To add to that, most fossil species consist of at most a few specimens. So it is not true that we have found more than one of everything. But more to the point, we have found seveal specimens of Austalopithicus, several different species in fact. So it is not true that we have only found one. There are numerous examples.

19. Can you believe in “the big bang” without faith?

First off, “the big bang” has nothing to do with evolution. It doesn’t even have anything to do with life on earth. You can accept evolution and reject the Big Bang Theory, they are completely independent. Second, yes, you can. Do you seriously think the physicists who came up with the theory just pulled it out of their butts? Or do you think they started with observations of the known universe. They did in fact start with observations and deduced the big bang theory based on physical and mathematical principles. It had nothing to do with faith, it had everything to do with observations of the known universe. It would also never have been accepted by other physicists if they couldn’t defend the math. It will also be unceremoniously dumped if anyone provides a better explanation. I don’t have the mathematical background to understand the evidence for the theory. Thus, I accept the Big Bang Theory because there are lots of people that do have the background and have examined it in detail and have not been able to demolish it yet. But by all means, if you want to learn the math well enough to take a crack at it, go for it. There are plenty of physicists that will be happy to help you out and study whatever you come up with. The Big Bang Theory actually got its named as a derogatory comment from Dr. Fred Hoyle, a physicist that did NOT accept the theory initially. But eventually, the math and observable facts won people over. No faith involved.

20. How can you look at the world and not believe someone created/thought of it? It’s amazing!!!!

I agree, the universe is amazing. I don’t think you can explore the world as much as biologists do without thinking the universe is amazing. But because I know something of how it works, I find it endlessly more amazing than if I didn’t.people become scientists precisely because they think the universe is amazing and awe-inspiring. So awe-inspiring in fact, they want to know more about it. They are not content to just sit back and ignore it. But the question has nothing to do with evolution. It again assumes that evolution and a Creator are mutually exclusive. As I stated above, and as so many religious leaders and religiously devout scientists have stated ad nauseum, it is OK to believe in God and still accept evolution as being true. Let me ask you, which is more amazing, God did it, or we are the descendants of stars that exploded billions of years ago, spreading their elements across the universe, which eventually coalesced into our planet and finally at long last became us? Is the story of our connection to the universe in a very real, physical way as living descendants of the stars any less awe-inspiring than God waved his appendage and poof we are here? Does one story mean the other didn’t happen? No, I don’t think so.

21. Relating to the big bang theory…where did the exploding star come from.

Again, nothing to do with evolution. Also, it wasn’t a star, stars didn’t exist yet. Finally, heck if I know, ask an astrophysicist. No way is an evolutionary biologist ever going to be able to adequately answer that question. You are asking the wrong people and associating things that have no connection to each other. This sort of question is like asking an Olympic swimmer to compete in the heavy weightlifting competition and then assuming he can’t swim because he lost the weightlifting competition.

22. If we come from monkeys, then why are there still monkeys?

First, we did not come from monkeys. Monkeys and humans both came from a common ancestor. Second, when you were born, did your parents die? What makes you think that just because one species evolved that the ancestral species has to go extinct? Life is not a perfectly linear ladder of existence. If it did work that way, there could only be one species on the planet at a time and that obviously isn’t true.  I assume everyone can agree that new phones use the technology of pre-existing phones and improve upon them. When the new phones are created, do all older phones magically disappear? I don’t think so. Or perhaps, do the older phones gradually start going by the wayside as they get replaced over time. Taking this even farther, did kids stop drawing their names in sand because the internet was invented? Did hieroglyphs on Egyptian obelisks vanish because of TV? No, they stuck around. The evolution of a species does not require the ancestors to die out. In fact, that rarely happens.

There you go, 22 answers to 22 questions. I hope it has become obvious that the objections people raise against evolution, for the most part, have nothing to do with evolution. Those that do have something to do with evolution are based on a serious lack of understanding about how the world and science works. The history of life truly is the greatest story ever told. Let’s focus on learning that story and spend less time on arguments about the existence of the publisher.

Myths and Misconceptions #1: Allosaurus rex, or That is NOT a Dinosaur

When I worked at the Denver Museum of Nature and Science as a volunteer in the educations collection (if you ever get the chance to volunteer at a museum, do it, it was a lot of fun and very educational), I happened upon a man with a young boy by his side, whom I presume was his son, looking at an impressive skeleton. I thought how great it was the man took time to bring his son to the museum. But when the boy asked what the skeleton was and the man answered, “Allosaurus rex,” my opinion of the experience dropped. I’m still glad he brought the boy to the museum, but it could have been so much better.

Allosaurus rex? Actually, a blue whale. Definitely NOT a dinosaur. Also, not DMNS. Really, the London Natural History Museum. Photo by author.

Allosaurus rex? Actually, a blue whale. Definitely NOT a dinosaur. Also, not DMNS. Really, the London Natural History Museum. Photo by author. Click to enlarge.

So what was wrong with what he said? There is no such creature as an “Allosaurus rex.” There is an Allosaurus and there is a Tyrannosaurus rex, but not the two together. It also did not help that the man was standing directly in front of the plaque that read, “Fin whale.”

Much has been written on what a dinosaur is and what is not, but considering the extreme levels of confusion in the general populace, I thought it worth discussing it here. Not everything that is a big skeleton and/or extinct is a dinosaur. In addition to the above whale, I have heard dimetrodons, pterosaurs, saber-toothed cats, mammoths, giant rhinos, mosasaurs, modern elephant skeletons and many other things called dinosaurs, when in reality, NONE of the previous creatures qualify as dinosaurs.

So, if none of those are dinosaurs, what is? What are some of the things people think about when they try to define dinosaurs? The first thing that most people think about is a giant, scaly reptile. However, some dinosaurs were the size of chickens, so not all of them were big. Many also had feathers, so the scaly motif is not altogether correct either. They are reptiles, but unlike anything most people would consider a reptile today.

Quetzalcoatlus northropi. UT Museum. Not a dinosaur either. Photo by author.

Quetzalcoatlus northropi. UT Museum. Not a dinosaur either. Photo by author.

Other traits people often use to distinguish dinosaurs are that none of them were aquatic and none of them flew. These aren’t really true either. Some will say they only lived in the Mesozoic Era and died out at the end of the Cretaceous Period  65 million years ago. Again, false. It is true that most animals considered dinosaurs did indeed live only in the Mesozoic Era, but not all died out at the famous K-T extinction event. Some of you may be thinking to yourselves the author has no idea what he is talking about. Nevertheless, as we will see, some dinosaurs are quite at home in both air and water, especially the ones that lived past the Mesozoic.

Even if all these things were true about dinosaurs, none of it really matters. These traits are all distinguishing characteristics that are generally true about most dinosaurs, but not necessarily true about all. What defines an organism is not the same as the diagnosis. Definitions are done by evolutionary relationships. Diagnoses tell us how we can recognize them, what distinguishing characteristics can be used. However, distinguishing characteristics do not necessarily describe all the members of the group. For instance, one might distinguish all members of a family by their last name, but if people get married and change their last name, they do not suddenly stop being a member of the family. A daughter, for example, is defined by who her parents are, not by what name she has. Likewise, her distinguishing characteristics tell us who she is as an individual and can give us clues to her family relationships, but her definition as a daughter depends solely on her relationship to her parents.


The discredited and completely unaccepted haemothermia hypothesis: Mammals and birds are both warm-blooded; therefore, they must be related. I.e., superficial similarities can be misleading. Image from wikipedia.

I should note here that it wasn’t always this way. Back in the old days, organisms were grouped by similarity, who looked like whom, so at that time, there was really no difference between definition and diagnosis. But as people studied organisms more closely, they found that a lot of times, superficial similarities masked deeper differences, which indicated they weren’t really related at all. So for most of the last century, scientists have tried to find real, evolutionarily related groupings to build something akin to a geneology of life. To do so, it became evident that definitions and diagnoses of groups had to be different, so for the last couple of decades, definitions have been based on relationships and diagnoses based on characteristics. This system of classification by defining groups according to their relationships is called phylogenetic systematics.

So, how then do we define a dinosaur? The standard modern definition of a dinosaur has been stated as the most recent common ancestor of Triceratops and modern birds and all of its descendants (Padian, 1997). Note this means that all birds are, by definition, dinosaurs. So it is obvious that some dinosaurs are quite small (e.g. hummingbirds), flew (most birds), and could reasonably be called aquatic (e.g. penguins). The reason for this is because the earliest birds are clearly closely related to animals, such as Velociraptor and its close relatives, which are indisputably dinosaurs. If one took a picture of Archaeopteryx which had no feathers to a bunch of elementary school kids and asked them to identify it, the general answer is that it is obviously a dinosaur, but put feathers on it and they call it a bird. They are thus both correct answers. Dr. Thomas Holtz has proposed a slightly different definition: the most recent common ancestor of Megalosaurus and Iguanodon and all of its descendants. Both definitions encompass the same groups of animals as far as our understanding goes, but Holtz’s definition includes the dinosaurs that were first discovered, so is considered by many to be a superior definition.


Dinosaur family tree, by Nobu Tamura ( Click to enlarge. Note on trees like this, the branches can be pivoted on their branch points without changing relationships (e.g.,it makes no difference whether you say “your brother and sister” or “your sister and brother”), so anything in Saurischia is equally related to anything in Ornithischia. Thus, it doesn’t really matter what animal in each group you choose as the representative of each group as long as the groups as a whole remain intact.

Unfortunately, scientists don’t always talk about these terms correctly either, making the whole process confusing. Michael Benton, a leading paleontology researcher with numerous well-respected publications, got it wrong when he defined dinosaurs according to synapomorphies in The Complete Dinosaur. While synapomorphies are used in developing modern classifications, they are used for diagnoses, not definitions of groups, which Dr. Benton assuredly knows (as evidenced by the fact he normally states it correctly in his other works), but when someone is as prolific as Dr. Benton, the occasional error is bound to slip in now and then.

Synapomorphies are very important in figuring out relationships. Unlike any old similarity, synapomorphies are shared, derived characteristics, meaning that the character is the same in the organisms being compared because they share a common ancestor, i.e. they are derived from the same source. Of course, because it requires knowledge of the common ancestor, synapomorphies can only be identified AFTER one has a hypothetical relationship. Thus, to discover strong relationships, scientists will create (mathematically, using a computer because it is way too complex to try doing by hand for anything beyond a few species), all the possible relationships between all the organisms under consideration and then map all the characteristics they can onto every possibility. The relationships requiring the fewest inconsistencies and providing the simplest explanation is considered the most likely. Inconsistencies can occur due to convergent evolution (organisms not closely related developing similar characteristics due to similarities in environmental constraints) or homoplasies (characteristics changing back to a previous form), but with examination of enough characteristics, good relationships usually appear. Of course, the more data you can put into the analysis, the better the results normally get, which is why we continue to study and try to find new fossils and collect more data (and who wouldn’t want more fossils?).

This is all well and good, but how then do we recognize a dinosaur when we see one? Dr. Benton provided a good list of skeletal characteristics, which really won’t mean a lot to people who are not very familiar with skeletons and scientific terminology (but a basic description can be found here and Wikipedia has a surprisingly in depth description). Nevertheless, there are some generalities we can make. If we exclude birds, we can say the non-avian dinosaurs (that we know of) died out at the end of the Cretaceous Period. They all carried their legs underneath their bodies like mammals (and birds of course) and were decidedly unlike other reptiles. None were fliers, although the most bird-like ones got close, and none were aquatic, although some did indeed at least go wading. But remember, these are generalities and if we find a dinosaur with flippers, as long as it otherwise appears related to other known dinosaurs, it will still be a dinosaur. But if it does not fall within the relationships defined above, it will not be a dinosaur, no matter how much it may look like one.

I don’t have an online source for the Padian article, so here is the reference.

Padian, K. 1997.  Dinosauria: Definition.  pp. 175-179.  In Currie, P.J. and K. Padian (eds.) Encyclopedia of Dinosaurs.  Academic Press.