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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 (Aristotle, Averroes)[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.
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.
Mystery Monday Fossil of the Week
Our Mystery Monday fossil concerns a photo taken by the Arkansas Archaeological Society on one of their digs. I’m still trying to find when this was taken, but I know roughly where. Can you tell what it is they are uncovering?
Fossil Friday
On Monday I posted a picture of a tooth from an animal that is a famous California resident, although is not generally considered an Arkansan. Were you able to figure it out?
The tooth is a canine from a Smilodon, the saber-toothed tiger (although not actually related to tigers). Smilodon fossils have been found in a few caves in the Ozarks of northern Arkansas, most notably Hurricane River Cave and the Conard Fissure (the Conard Fissure was excavated by Barnum Brown for the American Museum of Natural History, who also did a lot of famous dinosaur digs for them in the Rockies) . Originally, they were described as having come from two different species of Smilodon: S. fatalis and S. floridensis. Smilodon fatalis, sometimes called S. californicus, is well-known from the La Brea Tar Pits in California, although has been found throughout much of North America and Pacific coastal areas of South America. Smilodon floridensis was known primarily from, unsurprisingly, Florida and neighboring states. However, these days most researchers view them all as the same species, so just Smilodon fatalis. There are two other recognized species. Smilodon populator lived in South America and was bigger, with a few hundred more pounds on S. fatalis. Smilodon gracilis was half the size of S. fatalis and lived earlier than either of the other species, and is considered by some to be ancestral to them.
prehistoricpark.wikia.com
Smilodon fatalis is the quintessential Ice Age predator. It appeared about 2.5 million years ago and only died out about 10-13,000 years ago, so it may have been possible that Smilodon preyed upon early humans, at least along the Pacific coastal areas. It was a big, burly cat weighing up to 600 lbs. with heavily muscled forelimbs. Of course, it is best-known for its 7” long, serrated canines, thus the name Smilodon, meaning “carving knife tooth”. Smilodons were part of a group known as Machairodontinae, a subfamily within Felidae known as the “dirk-toothed cats.” These long teeth necessitated a jaw that could swing extraordinarily wide. Smilodon was specialized for killing large prey, such as bison, horses, and young mammoths and mastodons. Much debate has centered on how it dispatched its prey, with depictions of a Smilodon burying its canines in the skull or eviscerating its prey. However, more recent studies have indicated the canines were too fragile to withstand such treatment or couldn’t get a sufficient bite to properly tear into the abdomen. It is thought instead that Smilodon used its powerful forelimbs to stun and restrain the prey until it could bring its canines into play with its powerful neck muscles to slash the throat and cut the major arteries, causing the animal to bleed out quickly. They were not fast runners, preferring to attack from ambush, staying hidden within the vegetation of the forests and bushlands it preferred to live in.
Youngsteadt J.O., 1980: A saber toothed cat smilodon floridanus from hurricane river cave northwest arkansas usa. Nss Bulletin: 8-14
B. Brown, The Conard Fissure, A Pleistocene Bone Deposit in Northern Arkansas…,Memoirs of the American Museum of Natural History, Vol IX, Part IV, February 1908.
Fossil, and Forum, Friday
I’m sorry, but I forgot to post the Mystery Monday fossil on the blog. I posted the fossil on the Facebook page, but somehow failed to get it posted here, for which I apologize. Here is the fossil I posted, including the identifying portion cropped from the original picture. This image was taken from trilobites.info, a great website for all things trilobite.
Here is Bristolia for comparison. This image is also from trilobites.info
It was correctly identified as a trilobite, although this one is the species Irvingella, not Bristolia as was guessed. Irvingella is very similar, but lacks the tail spine and the second set of spines is a little farther down the body. They are both listed as “fast-moving low-level epifaunal” feeders by the Paleobiology Database, which means they scurried quickly about over the ocean floor. But whereas Bristolia is thought to have been a deposit feeder, much like a crawfish, Irvingella was a carnivore, preying on worms, bugs, and such. They both lived in offshore marine environments, but whereas Bristolia has been found mostly in shallower waters, Irvingella has been found widespread from offshore throughout the continental shelf and even deeper water. This may have more to do with Bristolia having only been found in a few places in the southwestern United States while Irvingella has a much broader range throughout much of North America and Asia. They both lived in the Cambrian Period, although Bristolia seems to have lived a little earlier than Irvingella (there are some discrepancies in the published records making it difficult to compare exactly, this is partly due to revisions of the time scale and refinements in age estimates over the decades making detailed comparisons problematic).
Since our last Forum Friday recap, we have started a new year. We have reviewed the Walking with Dinosaurs movie. We identified an Exogyra ponderosa oyster, Archimedes bryozoan, Aetobatus eagle ray, and this Irvingella trilobite.
Over on the Facebook page so far this year, we have seen some amazing animals, including sharks that glow in the dark, a fish that walks on land, and a caterpillar who’s tobacco breath repulses spiders. We even learned why sharks don’t make bone, but polygamous mice have big penis bones and an organism that changes its genetic structure seasonally.
A green biofluorescent chain catshark (Scyliorhinus retifer). Livescience.com. Credit: ©J. Sparks, D. Gruber, and V. Pieribone
We saw two articles on fighting dinosaurs. We learned how they took over the planet and discussed scaly dinosaurs for a change. We found out some ancient marine reptiles were black and Tiktaalik had legs.
A lot of articles hit the press on human evolution in 2013. We also found out (some) humans developed the ability to tolerate lactose to not starve and how we smell sickness in others. We also found a great book on Evolution & Medicine. We also saw evidence of how our actions affect the evolution of other animals and someone who thinks they can understand dog language.
We read that plants may have caused the Devonian extinction event, a genetic study saying placental mammals originated before the end-Cretaceous extinction event despite no fossils ever having been found, and that small mammals with flexible schedules handle climate change better than big mammals that keep a stricter schedule.
We found a great , concise explanation of evolution and three different short videos on the history of life on earth, two of them animated and set to music. We also heard Neal DeGrasse Tyson urge more scientists to do more science outreach (and how to cook a pizza in 3 seconds). Unfortunately, we also heard about the deplorable conditions during filming on Animal Planet and creationism in Texas public schools, as well as how the failure to take evolution into account can screw up conservation efforts.
So what did you like? Did you guess the fossil? Is there anything you want to see? Let us know.
Fossil Friday
Another week has gone by and so little done here. I started my Vertebrate paleontology class this week and if you think it takes a lot of work to take one, just imagine the amount of time it takes to design one.
So today, we announce the mystery fossil from Monday. Did you have any idea what it was? It stumped everyone on the Facebook page, so if you couldn’t figure it out, don’t feel bad. It was a hard one. These are not terribly uncommon fossils, but most people are completely unfamiliar with them, despite the fact that anyone who visits a public aquarium has seen its living relatives.
This is part of a tooth plate from a ray, most likely Aetobatus, the eagle ray. They are filter feeders eating plankton and have been around since the Miocene 20 million years ago. While none have been found in Arkansas that I know of, they have been found in pretty much every state around us, so I expect so collector out there somewhere has probably found some here. Check us out Monday for a new fossil!
Spotted_Eagle_Ray_(Aetobatus_narinari). Wikipedia.
UPDATE: I need to correct a mistake I made in this post. Eagle rays, like Aetobatis here, were and are not filter feeders. The large rays, like the Manta ray in the same family, are indeed filter feeders, the smaller rays, like Aetobatus and its close relative Myliobatis, another ray that lived in the area at the same time (as well as earlier in the Eocene over 40 million years ago), were durophagous, meaning they used their teeth to crush shelled prey, such as clams, crabs, and shrimp. The main part of the tooth brought to bear on the prey item is the flat, plate-like part.
For this picture and much more information on the current species of eagle rays, go to the Florida Museum of Natural History.
Fossil Friday
It has been a strange week, what with trying to catch up from the holidays and all. So this post will be brief. On Monday, I posted this picture of a commonly found fossil in Arkansas, provided you look in the right places. Here were the clues.
Clue 1: It’s from the Cretaceous.
Clue 2: It’s modern day relatives are widely considered a delicacy.
Clue 3: This is no wilting lily. This creature is big and bold. It shows how twisted it is on the outside for all the world to see. Dude, that’s heavy.
Were you able to figure it out?
So for the final reveal: Exogyra ponderosa. Allie Valtakis was able to figure out it was a mollusc, specifically a bivalve (clam), in the Order Ostreoida, Family Gryphaeidae. While mosasaurs swam the oceans and dinosaurs walked the shores, these Late Cretaceous oysters made huge oyster beds throughout the coastal waters. Like all oysters, they were filter-feeders, collecting microscopic particles of food from the water. You can find them in south-central Arkansas within several rock units, but most particularly in the Marlbrook Marl, a limy mudstone. They are known for their large, heavy, rough bottom shell with a curled, hornlike part near the hinge. The top shell is much smaller and flatter, but still a good size, something like a cap on a coffee cup, if your coffee cup was kind of bowl-shaped. They are sometimes called Devil’s toenails, but that name usually refers to a different clam called Gryphaea, an oyster that is also in the Family Gryphaeidae, but a different subfamily. If you look under a microscope at the shell, you may notice that it is very porous, giving the Family the nickname of foam or honeycomb oysters. Some are still alive today, such as Hyotissa hyotis, the giant honeycomb oyster
E. ponderosa was one of the earliest clams of this genus that was named, by Ferdinand Roemer in 1852, a German lawyer who gave up law to study geology in Texas, thus his title as the Father of the Geology of Texas. You can fossils of them from Texas to New Jersey and Delaware, south through Mexico and Peru.
Until next time, as Dr. Scott The Paleontologist would say, ‘Get out there, get into nature, and make your own discoveries.”
Mystery Monday and Walking With Dinosaurs Movie Review
Mystery Monday
Last Friday I posted clues to a mystery fossil. The clues were 1) I lived in AR during the Mississippian Period roughly 330 million years ago and am a very common fossil to find here. 2) Many people think I’m a coral, but I’m not. 3) I am named after a famous Greek mathematician and inventor. Who, or more precisely, what am I? Allie Valtakis got the right answer as the bryozoan, Archimedes. Here is what the Arkansas Geological Survey says about it.
The Bryozoa grow attached to the sea-floor as do corals, but they differ significantly from corals in terms of soft-part anatomy. The bryozoans are exclusively colonial and fall into two broad groups, the lacy colonies and the twig-shaped colonies. Individual “houses” (zooeciums) lack the radial partitions found in corals, but they are divided transversely by partitions called diaphragms (Fossils of Arkansas). Bryozoans can also grow as incrustations on the shells of other organisms and are commonly associated with reef structures.
“Bryozoans are tiny colonial marine animals that are present in marine and fresh water today. They are sessile benthonic animals (fixed to seabed) that are filter feeders and prefer shallow seas, living fairly close to shore (neritic). One bryozoan called Archimedes (see picture below) is abundant in Mississippian age rocks in Arkansas and is so plentiful that one of the rock formations called the Pitkin Limestone was once referred to as the “Archimedes Limestone”. Generally, only small pieces of bryozoans that resemble “fronds” are preserved in Mississippian and Pennsylvanian age rocks in the Ozark Plateaus Region.
References:
Freeman, Tom, 1966, Fossils of Arkansas: Arkansas Geological Commission
Bulletin 22, 53 p., 12 pls., 15 figs., 1 map.
Archimedes “fronds”
Way to go, Allie!
Can you guess this week’s fossil? I will do things a bit differently this time. Unlike previous fossils, in which I told people on the Facebook page as soon as someone provided the correct answer, I will not reveal the answer until Friday, so you have plenty of time to give it a try. In addition to the picture (note the scale) below, I will provide one clue every day until Friday. Good luck!
Clue 1: It’s from the Cretaceous.
Clue 2: It’s modern day relatives are widely considered a delicacy.
Clue 3: This is no wilting lily. This creature is big and bold. It shows how twisted it is on the outside for all the world to see. Dude, that’s heavy.
Come back tomorrow for the answer! You can also find it on the Facebook page.
Walking with Dinosaurs 3D movie review
I went to see Walking With Dinosaurs 3D this weekend. My kids were interested in seeing the movie and I liked the BBC “Walking with Dinosaurs” TV mini-series, so we were all eagerly anticipating the movie. I had read a few reviews of the movie, some by paleo people, who said the dinosaurs were great, but the voices were terrible, which gave me pause, but it’s a BBC movie on dinosaurs, how bad could it be, right?
Sadly, not like this.
Sad to say, I have to agree with most of the reviewers. This movie may be much more enjoyable if you can’t hear it. To begin with, whatever expectations you may have, forget them. If you are going in expecting to see a big screen version of the BBC “Walking with Dinosaurs,” you will be disappointed by the cartoon voices and plot. If you are looking for light entertainment for little kids, you might be a bit surprised by the rather jarring breaks providing a subpar, documentary-style educational interlude which will kick everyone out of the story.
More like this, but with better graphics.
The film reminded me nothing so much as a cross between the BBC documentary-style series and The Land Before Time movie series, failing at both. I think the reason for this is because it seemed to clearly start off with the idea of it being a kid-friendly movie along the lines of the TV series, but some executive decided after it was made that it was not going to draw enough kids. So the movie was recut and really bad dialogue added to it instead of the normal narration one would expect in a nature documentary, along with completely superfluous modern scenes bookending the film, wasting the talents of otherwise fine actors. The voices were obviously added as an afterthought because the dinosaurs do not act like they are speaking. I could even occasionally hear the original dinosaurian bleating and honking in the background even as they are supposedly talking. The dialogue, as Brian Switek noted in his review, destroyed any emotion that may have been evoked by the scenes that were supposed to be emotionally powerful. What should have been poignant, heart-tugging scenes were drained of any impact by juvenile pratterings that never ceased. I found myself wishing for the dinosaurs to just shut up once in a while. As a result, it is a movie that may be enjoyable for a little kid, but eminently forgettable. Bambi was a much more riveting emotional experience, not to mention more educational about the lives of deer.
The story line was inconsistent with the idea of a nature documentary and a poor choice for a dinosaur movie. Whether or not the worst aspects of it were in the original script, I don’t know, but the final plot, while suitable for a cartoon Land Before Time, was wholly inappropriate for a nature “fauxmentary.” For a film that was supposedly educational, it pushed moral viewpoints which are only valid in human cultural environments and completely invalid in the natural world. The idea that intelligence and courage will overcome the thoughtless, testosterone-fueled belligerence of the larger alpha males is a noble sentiment and may work in a human context, but not in the depicted dinosaur society. Control of a herd of large herbivores that have evolved extravagant displays will never pass to the runt of a litter because he saves the herd in a time crisis due to his quick thinking. The plot line for the movie is far more appropriate to an after-school special involving actual, human children, not dinosaurs. As such, it completely destroys any educational effectiveness of the movie. The only education that remains is that dinosaurs lived in a snowy Alaska and that some dinosaurs had feathers, particularly the smaller theropod carnivores. I really like this aspect of the movie, but its authenticity in these aspects was completely undermined by the silliness of the rest of the movie.
To make it even more confusing in terms of genre plotting, the movie shows that females in the herd are dominated by the alpha male, but glosses over what that means in terms of sexual dominance. In a kid-based movie, this understandably only goes as far as hanging out with each other. In the natural world (and post-adolescent human worlds), as every adult in the audience will understand, it means the female submits to the alpha male’s sexual advances. In terms of a human kid’s movie, it sends very poor messages about the role of females in society. In terms of an educational nature show, it is intentionally misleading to spare the typical parental sensibilities of what is appropriate for kids to see.
In short, if you go to see this movie (which I would really recommend waiting until a rental, as it is not worth spending the price for a 3D movie), go expecting to see a mindless 80 minutes of passable, but forgettable, entertainment for children with no real educational value other than to say look, aren’t dinosaurs neat? Enjoy the graphics, ignore the rest.
Day 4 at SVP
Day 4 and the last day at SVP. After this, we will return to our regularly scheduled sorts of posts.Another day of talks and poster sessions, the last chance to meet friends and colleagues and discuss what you’ve heard and what people are doing. Although frankly, I think most people are tired and ready to go home by this point. Some people thrive on the highs of shared creativity and knowledge and find the end of the meeting and going back to regular work depressing, I think the most common reaction is the feeling of being rejuvenated by the meeting, so that you can’t wait to go back and start developing the new ideas created at the meeting, the chance to put those creative juices to work before the distractions of everyday life dry them up.
A lot of people don’t like having their talks on the last day. People are going home, they are tired, their attention flags, but this meeting showed a strong turnout for the last set of talks. The symposium scheduled for today was “Patterns from the poles: biodiversity and paleoecology of high latitude fossil vertebrates,” which I, at least, found interesting and worth attending. I didn’t attend too many of the talks though, because there was also a session on the evolution of early birds, which I found even more interesting, as well as a session on mammals, which had several talks discussing how different mammal groups adapted to climate change in the past. Several talks introduced new fossils and what they contributed to our knowledge of evolution within those groups, such as a new Devonian fish from Siberia, the first pterosaur from Antarctica, a new sauropodomorph (early versions of animals that would become sauropods, the oldest mammal from Antarctic and a new Arctic camel, new birds, seals, sirens, dolphins, and whales. All in all, good reasons to stick around.
Anchiornis_martyniuk, wikimedia
Rui Pei reported on a new specimen of Anchiornis, the first animal in which fossil evidence in the feathers was used to determine coloration. Anchiornis lived 10 million years before Archaeopteryx and there has been some debate about whether it was a true bird or still a non-avian dinosaur. Pei’s analysis of the new specimen indicated that Anchiornis was a troodontid, so not quite yet a bird. This is another great example that the transition between birds and other dinosaurs is so well documented that the line is an arbitrary classification with no biological relevance. Speaking of feather colors, William Gearty found new ways to study the melanosomes in the feathers providing colors, finding that, in addition to color, he could tell color gradients as well. he also concluded that melanosomes stiffened the feathers, making them more resistant to wear, but also carried more bacteria, thus representing an additional resource cost for the animals (some of this work can be found online at PLOS One).. Justin Hall found that feather asymmetry, long thought to be important for flight, turned out not to have the aerodynamic significance we thought, as it didn’t really affect the ability to fly. Ashley Heers found trade-offs in locomotor ability: the more investment in wings, the less was put into the legs, and this trade-off could change as the bird grew so that chicks may emphasize the wings or legs while the adults emphasized the other.
Cryolophosaurus, Royal Ontario Museum. Wikimedia.
Several studies showed the difficulties inherent in paleoecology interpretation. Peter Makovicky found that the horned ceratopsids showed different growth rates between northern and southern populations, the duck-billed ornithopods did not, and the carnivorous theropod Cryolophosaurus showed different growth rates in different areas of the same body in the northern individuals, but not in the southern individuals. According to Bergman’s rule, we should expect to see animals get bigger and stockier the farther north they are found. Anthony Fiorillo found that the small troodontids followed the rule, but northern individuals of the large tyrannosaurs were only 40% the size of the southern ones. In this case, it is likely that resource supply kept the tyrannosaurs smaller. Patrick Druckenmiller reported on a diverse Arctic dinosaur fauna including toodontids, dromaeosaurs, thescelosaurs, hadrosaurs, pachycephalosaurs, and tyrannosaurs, despite mean annual temperatures near freezing. While similar to southern forms, all the species were different, indicating a discrete, provincial ecosystem. John Tarduno argued that the presence of champsosaurs (a type of early crocodylian) and turtles indicated the weather was too warm for ice to be present even during winter, but as proven by an earlier talk, we know this is incorrect (a great example of science correcting itself). He proposed volcanism forming a series of shallow, freshwater connections between North America and Asia during the latest Cretaceous allowing interchange between the continents, which will need more study to determine if that proposal is true. Judd Case found that even though modern fish fauna show a drop in diversity with lower temperatures, thisi was not the case in the Cretaceous. As the temperature in the Cretaceous dropped 8-10 C in the Antarctic oceans, the fish didn’t really change, although marine reptiles increased in diversity while the ammonite diversity dropped.
Figure from Fletcher et al. 2010, showing FEA analysis, indicating stress points near the joint.
Rodrigo Figueiredo presenting evidence that predators who pursue their prey (as opposed to ambush predators attacking large prey and those that pounce on smaller prey) may not have evolved to go after herbivores, but to prey on the pounce predators themselves, much like wolves will sometimes hunt foxes and weasels. Michael Greshko presented a study finding that herbivores known as generalists (able to eat a wide variety of plants) mostly consist of different individual specialists who eat only a narrow range of foods. This is rather like why a pizza buffet needs to stock a lot of different types of pizza even though any particular customer may only eat one or two different types. Speaking of eating, Emily Rayfield gave a possible answer to why mammals reduced the number of bones in the mandible to just one, as opposed to having several bones in the lower jaw like other groups of animals. Using Finite Element Analysis, an engineering method designed to test mechanical strength of materials, found that the one bone provided a stronger bite while reducing stress. Alistair Evans used a program called GEOMAGIC to study tooth shape in early mammals and predict what tooth shape should be like to help sort out all the isolated teeth for which we have no idea what they belong to. in this way, he is making predictions of fossils that have not yet been discovered.
Gephi.org BON graph
In addition to the software programs mentioned previously, several others were mentioned in talks this day. Most biogeography methods these days are done using phylogenetic methods to help inform how animals spread out across the globe, but Chris Sidor presented Bipartite Occurrence Networks (BON), using Gephi to visualize the patterns, which just uses locality connectedness and found that therapsids (proto-mammals, aka mammal-like repties) were pretty widespread and cosmopolitan before the Permian extinction event, but became much more provincial and limited in range afterwards. Paul Upchurch used TREEFITTER to map pterosaur biogeography, finding support for sympatry (speciation within the same region) with an origin in eastern Asia. Diego Pol used Ancestral Area Reconstruction methods to conclude that dinosaurs probably originated in South America, along with most, but not all, mammals, but crocodylamorphs originated in China. Graeme Lloyd used GEIGER to study evolutionary rates and Akinobu Watanabe used PERDA (Polymorphic Entry replacement Data Analysis, a script running in TNT, a phylogenetics analysis program) to simulate poor sampling of phylogenetic data, finding that if a trait, or character, has multiple possibilities within a single species, it seriously messes up results unless multiple individuals covering all the possibilities are included in the analysis. John Alroy found that no current method is very good for finding the first appearance of taxa, but Bayes Theorem methods, such as used in MrBayes, produce better estimates of extinction times.
Figure from Sansom and Willis 2013 showing fossilization study results.
The last two talks I would like to mention are from Robert Sansom and David Grossnickle. Sansom found that loss of soft tissue characteristics resulted in changes in cladograms drawn from the data for vertebrates, but not for invertebrates. In other words, if one only looked at hard parts, the evolutionary relationships changed, and more often than not, made the animal appear to be more ancestral than it really was. This occurred even if the characters were recorded as unknowns and not simply listed as absent. Grossnickle looked at morphological disparity in Mesozoic mammals, i.e. the diversity of body form. What he found was that most Mesozoic mammals were carnivorous/omnivorous, with a low level of diversity which gradually increased until the middle Cretaceous. At some point in there, they hit a botttleneck. Their diversity crashed and, while it did start going up again,never reached the previous diversity levels until after the K-T extinction event. What is interesting about this is that pretty much everything else was diversifying, while mammmals were not. Another interesting thing about this is that according to molecular data, mammals were diversifying, so the apparent diversification did not show up as morphological diversity.
This is the end of my discussion about the science presented at SVP. There were so many more talks and posters that I did not mention and i make no claim that the ones I mentioned are even the best or most important, nor are they even all the ones I attended and learned something from, but it would take me until the next meeting to discuss all of them. The point is that meetings like this are incredibly fascinating places to see what is going on in science right now. Anyone who thinks science is a bunch of stale facts in textbooks or that scientists even pretend to have all the answers is seriously mistaken. The search for truth is asymptotic, you can get ever closer to a totally clear understanding of reality, but you will never reach it. Science is all about going over the data, tossing out ideas that don’t succeed and developing ones that do, with each step opening up new avenues of exploration.
Steven Spielberg on set of Jurassic park. Spielbergfancluc.com
I will end this discussion with the awards banquet held on the evening of the last day. During this banquet, we are told how much the auction collected to support the society, important news, memorials for those we lost recently, and people are recognized for their hard work and contributions to the field of vertebrate paleontology. Students are awarded their prizes and scholarships they have won, artists are awarded for best art in different categories, and people are recognized for outstanding careers that have progressed the field. This year, one of the biggest awards went not to a scientist, but to a science advocate. Perhaps because the meeting took place in Los Angeles, special recognition went to Steven Spielberg, for the money he has donated to the Jurassic Foundation and other places to support paleontology research and education and for the Jurassic Park movies, which brought paleontology to the center of the public eye and has inspired many to enter the field and make their own contributions. Officially, the meeting ended here. There was an after-hours celebration, which is always fun from what I hear, but I was beat and had a plane to catch early in the morning, so I called it a day. Until next year!
Day 3 at SVP
Another day at SVP, another boatload of information. Some may be wondering why I am devoting several posts to this meeting,when it may seem not as relevant to the general public. Fair question. people not actually doing science in an academic setting rarely get a chance to see anything about what it is like. Science is often presented as a list of facts, but that is only part of the story. Science is a dynamic endeavor, never being satisfied with an answer, always working on the things we don’t know and revisiting the things we thought we knew to see if they still hold up under the new information. Science gets things wrong all the time, but this process of study and review and critical examination reduces the margins of error. Not all things that are wrong are equally wrong, rejecting evolution in its totality is a whole other category of wrong compared to disagreements about the rates of evolution in a particular lineage. No one in science who examines the evidence seriously disputes evolution or that dinosaurs existed, but exactly how evolution works, how dinosaurs lived, exactly who is related to whom; these are questions that people struggle with. With each new study, the path moves closer and closer to the truth, each time having the possibility of opening up whole new avenues of exploration we had never thought of before. That is what these meetings are all about, bringing minds together for new solutions to old questions and for finding new questions to ask about old solutions. What goes on at meetings is a glimpse behind the curtain of published papers and distilled textbooks, putting human faces onto that quest, faces that are, more often than not, students working together and with more experienced people. Most science is done not by white-haired old men in the lab, but by young, energetic students with a zest for learning. And there is so much more to do.
In the previous two days, there were collections of talks called symposiums, devoted to specific topics, such as on ontogeny and the la Brea tar pits, including a preparators symposium on fossil collection and preparation techniques. Friday included a special symposium on the tempo of evolution and dating the fossil record. Samuel Bowring presented the EARTH-TIME Initiative, an opportunity to date the stratigraphic record to a precision never before seen, allowing measurements as refined as +/- 20,000 years all the way back to Triassic times (>200,000,000 years ago). That is a resolution of 0.01%. The remaining talks were about research on specific areas and times contributing to that increased precision.
Tar pits at the Page Museum. http://www.tarpits.org
Terry Gates looked at cranial ornamentation in theropod dinosaurs, finding only larger theropods used bony ornamentation and that if a lineage developed it, the lineage quickly developed larger species. So the question now is why were bony cranial ornaments only selected for larger body sizes? Yuong-Nam Lee reported on new fossils of Deinocheirus, an enigmatic fossil previously known only from one set of huge arms, which allowed them to determine it was the largest ornithomimosaur ever found, sporting a large sail on its back near the hips, something like a small spinosaur sail. Picture a giraffe-sized ostrich, with a sail on its back, giant arms with huge claws, and a big,chunky tail. On second thought, maybe not so much like an ostrich, after all.
Deinocheirus. By Nobu Tamura.
Other dinosaur reports include Ashley Morhardt, who reported that Troodon had the largest encephalization quotient of any non-avian dinosaur (i.e. it had a big brain). Most of its brain was made of the cerebrum, which not only makes a reasonable case for it being the smartest dinosaur, but supports a mosaic model of brain evolution, meaning that different parts of the brain evolved at different rates. Amy Balanoff discussed the evolution of oviraptorosaur skulls and brains, showing larger cerebrums than most other dinosaurs, but reduced olfactory tracts, so they were similar to birds in having a relatively poor sense of smell. Walter Persons reported on fossils showing that Microraptor ate mostly fish, as well as small mammals and birds.
A session devoted to mammals had several interesting talks, such as one by one by Ross Secord, who concluded from his research that the body size increase seen in horses was related to warmer temperatures allowing an longer growing season causing increased availability of grasses, making up for the lesser nutritive value of grasses compared to other plants. I would argue however, that a shift to eating hard-to-digest grasses would result in increased body size not through increased availability, but to increase digestion efficiency. Horses are what is known as hind-gut fermentors, which is less efficient than the foregut fermentation seen in ruminants such as cows. This mode of digestion is more efficient at higher body sizes, allowing more time for digestion. Lindsey Yann found that horses were too much of generalist feeders to be useful for paleoclimate reconstructions, but different camel species were more specialized and could used to make determinations of relative aridity and plant cover. Rebecca Terry found that interactions between mouse species had at least as large an effect on population sizes as climate, with different species reacting differently to resource changes. Thus, there is no easy answer to predicting how species will react to climate changes because they cannot be looked at without understanding interactions throughout the entire ecosystem. Much of this sort of work uses MIOMAP and FAUNMAP, which are similar paleontology databases to the Paleobiology Database, but limited to mammals in North America and so may be more complete for these types of studies.
Hemiauchenia, an early North American camel. Drawing by Gavin McCullough.
Brady Foreman discussed ways to interpret the completeness of the fossil record based on river deposition patterns and Patrica Holroyd discussed the “missing marsupial problem,” finding that because most eutherian mammal fossils are identified to species level and most marsupial fossils cannot identified beyond “marsupial,” there is a taxonomic identification bias in the literature and thus, species diversity studies.
Three other studies I would like to mention are about archosaurs, the “ruling reptiles,” including crocodilians, dinosaurs, and birds. Brandon Peecook looked at the bone microsturucture of Nyasaurus, which was either the earliest known dinosaur or the closest basal archosaur to it, and found that it had elevated growth rates compared to other reptiles, indicating that all dinosaurs may have had faster growth rates from the beginning. John Sarrazin reported that crocodilians and birds both use unidirectional air flow through lungs,as opposed to bidirectional like mammals, which uses a completely aerodynamically controlled system with no structural valves, so in all likelihood, the ancestral archosaur had these characteristics as well. Finally, Jennifer Nestler found that cold weather is not what limits the range of alligators. Rainfall contributed more than 60% to range limitations, most of the rest comes from warm weather during the summer providing long breeding seasons. Only 0.4% of the factors limiting their range could be attributed to cold weather limitations. Something to think about as global warming causes longer summers with elevated rainfall in the eastern United States.
Air flow in a croc lung. d = dorsal, v = ventral. Figure 10 from Schachner et al. 2013. PeerJ 1:e60
At the end of the day, after the talks and the poster sessions, this is the day for the annual auction, to raise funds for the organization that can be used to fund research and travel grants for students in the upcoming year. The auction consists of two parts, a silent auction and a live auction. In the silent auction, everyone has two hours on which to bid on the objects they want and the last bidder wins, much like alive version of eBay. The auction is filled with a wide array of donated items, everything from rare books and artwork to hand-knitted dino-themed baby socks, whatever people are willing to donate. After the silent auction comes the live auction, usually filled with more expensive, one-of-a-kind items, such as original artwork or the original copy of O.C. Marsh’s dinosaur monographs. I have even seen the services of a field cook and her personal field kitchen for a season get auctioned off. The auctioneers always have fun with it, usually dressing up in costumes. you never know who is going to be serving as auctioneer, it could be a zombie, King Tut, or Superman, but regardless, it is an entertaining spectacle.
Auction committee for SVP 2013. Photo by Neffra Matthews.
An end to another day, only one more day to go, before everyone packs up to go home, or off to their next meeting, or a museum to do research, wherever their path leads them.
Day 2 at SVP
Another day, another long list of talks and posters to see. Here is a brief synopsis of the talks I attended. I only wish I had the time to fully discuss everything that went on and all the material covered, but that would take volumes of material and far more time than I have. As before, if any of the talks sound sufficiently interesting that you want more information, please ask and I will discuss them in more detail. I realize that there are a lot of terms and creature names that may not be familiar to all readers, but the greatest learning takes place when one asks questions, so ask and ye shall receive.
Adam Huttenlocker showing fossils to kids at the Burke Museum. Photo by Lara Shinn.
The big session for today was for the Romer Prize. Alfred Romer one of the most influential vertebrate paleontologists of the 20th century, so every year, SVP awards the Romer Prize to the best presentation by a predoctoral student. A student usually applies within a year of completing their PhD. Those that successfully apply give a talk in the Romer session at SVP, which are voted on by the prize committee and awarded at the end of the conference. It is the highest honor a vertebrate paleontology student can win and so is quite an honor. This year went to a friend of mine I went to grad school with by the name of Adam Huttenlocker.
The first Romer talk I attended was by Stephen Brusatte, who talked about theropod dinosaur phylogeny, finding that while there is good support for a number of relationships in the theropod lineage, we still don’t have a good handle on how the early coelurosaurs, such as tyrannosaurs and ornithomimids, fit into the theropod family tree. He was able to conclude, after a detailed analysis of birds and their closest nonavian dinosaur relatives, that there is no real distinction to be made between them that truly delineates birds from other dinosaurs, giving further support to the dinosaur-bird hypothesis. Nevertheless, once birds did evolve, they evolved quickly, rapidly diversifying. Stephanie Drumheller looked at bite marks to see if you can tell the difference between crocodylians by what damage they leave on the bones. Thomas Evans looked at literally thousands of bones in rivers and found that what we have traditionally expected bones to look like after being carried downstream did not really match the reality at all, forcing us to have to rethink our assumptions of how much we can really say about fossils based on their condition. Adam Huttenlocker examined the “Lilliput Effect” after the Permian extinction. It has been noted that after mass extinctions, animal body sizes decrease, but exactly why that occurred was unclear. What Adam found was that selective extinction of the larger, faster-growing groups was the best explanation in this case. One might ask what other possibility might there be, which would be that all the animals simply got smaller, with some going extinct, but Adam found that smaller species did not alter their size through the extinction, they just survived when the large, fast-growing species died out. Neil Kelley was able to determine, in large part, the diet and feeding behaviors of most ichthyosaurs based on their morphology. Stephan Lautenschlager did a detailed study of therizinosaurs found that having beaks reduced stresses on their jaws and their famous giant claws were likely used to hook and pull vegetation, not for digging or fighting (at least, not primarily). Yasuhisa Nakajima used 3D micro-CT analysis to determine changes in bone growth and how much that can tell us about growth in extinct animals and James Neenan provided the first complete phylogeny of placodonts, the earliest group of marine reptiles.
Blood supply in the turkey. By William Porter.
Dinosaur noses got a lot of attention this meeting. William Porter mapped blood circulation in the dinosaur Camarosaurus, A.W. Crompton studied the evolution of turbinates in the nasal passages of early therapsid mammaliforms, indicating that they may have originated as a countercurrent heat exchanger to help regulate body temperature. Tomasz Owerkowics also discussed the role of turbinates in mammals in thermoregulation, but found they do not serve that purpose in birds or other reptiles. Along the way, they discussed the evolution of the different breathing apparatuses in mammals and reptiles. Robert Eagle also looked at dinosaur thermoregulation, but did so using carbon and oxygen isotopes measured together, which indicated a mammalian level body temperature for sauropods, but somewhat lower for oviraptors (although still higher than modern reptiles). Having large brains is often linked to higher metabolism and both ornithomimimosaurs and troodontids have been considered to have large, almost avian-like brains, but Harry Jerison found that at least their forebrains, while large for most dinosaurs, were still lower than avian forebrains. Going back to therapsids and the permo-triassic extinction, Jennifer Botha-Brink found that therapsids showed reduced life span and earlier reproductive maturity after the extinction event, consistent with what one might expect from populations that lived through an ecological catastrophe with reduced resources.
In strictly morphological evolution studies, Gabriella Sobral found that the fenestrated middle ear, which helped improved hearing capabilities, was not a unique event, but evolved independently six times within dinosars alone and was even rather inexplicably lost in stegosaurs, ankylosaurs, and oviraptors. Henry Tsai looked at hip joints in saurischian dinosaurs and found the femur did not fit the hip socket very well, indicating a lot of soft tissue must have been present in life and that the amount of soft tissue increased as the animals got bigger. Nicholas Campione came up with a new way of estimating body mass for bipeds to get around the fact that the standard equations were designed for quadrupeds and don’t work all that well for bipeds. It turns out that a simple correction factor of the standard equations worked fairly well, simply multiply by the square root of two. now to figure out just how well that really works and why. One potentially confounding factor is that it was based on living birds. I doubt it would hold true if used on say, a kangaroo. Finally, the last talk I want to mention was by Kevin Padian, who after discussing the earliest known bats, proposed that they never glided, but instead used their early wings to make a fluttering, control descent from trees. In his view, bats evolved from mostly terrestrial forms that ran up into trees to avoid predators (much like Dial‘s talk of the previous day), were insectivorous, and jumped out of trees to flutter farther and farther distances. He openly admitted this part was currently speculation and will need much more evidence before it should be accepted as definitive, but was a plausible hypothesis which can be tested, which I think is the mark of a good scientist, clearly delineating between what we know and what we think, between fact and a possible explanation.
So what of this, if any, looks interesting to you? What would you like to know more about?
paleoaerie 