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The Natural History Museum Book of Dinosaurs

If you are ever in London, the Natural History Museum (NHM) is a must see attraction. It ranks among the top natural history museums around. Schedule more than one day to see all the exhibits if you can, including their popular dinosaur exhibit that always draws large crowds. Many people have complained about the poor lighting and limited viewing space in that particular exhibit, but even with that, it is not to be missed. Accompanying the dinosaurs in the museum is an extensive online collection of fossil information, covering a wide range of dinosaurs. So given this, it should not surprise anyone that the NHM has put out a dinosaur book. The first edition of the book came out in 1993, with three more editions published since then, the latest one in 2006. We know a lot more about dinosaurs now than we did even ten years ago though, so how well does it hold up? Pretty well, for the most part, although a few Americans might be a bit perplexed by the British spelling that is occasionally different from American English. The NHM has a nice website on dinosaurs, which serves as a nice supplement to the book.

It is a long review, so if you want to skip to the summary conclusions, click here.

The Natural History Museum Book of Dinosaurs

51t8mO3z0sL._SX390_BO1,204,203,200_by Tim Gardom and Angela Milner

Publication Date: 2006. 144 pg.

Carlton Books. ISBN: 1-84442-183-X, 978-1-84442-183-1

AR Book Level: Not listed

Recommended for 10-14 year olds

Angela Milner has been a well respected paleontologist for decades and has been the leading researcher for dinosaurs at the NHM since the eighties, so if anyone is going to write a book about dinosaurs for the museum, it’s Dr. Milner. Tim Gardom is primarily known for this book, but he has had extensive experience writing for museum exhibits, including the dinosaur exhibit at NHM, meaning that he has practiced the art of writing technical material in a way that can be readily understood by nontechnical and diverse audiences.

This book can be considered an extension of the exhibit at the museum, taking what is there and expanding upon it considerably, forming an extended guidebook. It is not a catalogue of dinosaurs, though, such as Brusatte and Benton’s Dinosaurs. This book places dinosaurs in context within their world, focusing more on what dinosaurs were and how they lived over listing the different types, although it does that as well. More importantly, it talks about how paleontologists came to the conclusions they have, what is the evidence for what we think.

While extensively illustrated with a wide array of photographs of real fossils, paintings and illustrations of reconstructed dinosaurs, and the people and places, it is not a picture book. The text is extensive, but easily readable and should be readily accessible by any interested kid of middle school age or beyond, while still being a good read for adults.

The book has ten chapters broken up into an introduction to dinosaurs and the Mesozoic Era, five chapters on the lifestyles of the dinosaurs, an obligatory chapter on dinosaur extinction, a chapter on the history of dinosaur research, a chapter dealing specifically with how paleontologists piece together the clues to interpret the fossils, and finally ending with the now seemingly obligatory chapter on the evolution of dinosaurs to birds.

Chapter one is noteworthy for its debunking of some popular myths about evolution in general and dinosaurs in particular. It starts immediately with dispensing with the old chestnuts of “survival of the fittest” and the idea that dinosaurs died out because they were not “fit”. They properly describe evolution as being a product of those who are more capable of surviving in a particular environment and successfully reproducing, not necessarily the biggest and strongest. They go on to discuss what types of fossils are found and how they are formed which, while in general good, neglects the important contributions of microbes to the fossilization process. But to be fair, we know much more about that now than we did then and the purely physical processes listed here are still described the same way in almost every book published today. They also do a good job describing what a dinosaur is and is not. They separate animals commonly thought to be dinosaurs, such as dimetrodons, pterosaurs, and marine reptiles, from true dinosaurs. The biggest problem with this section is that the illustrations are poor. The Tyrannosaurus would not pass muster in the first edition, much less now, and the Deinonychus is out of date. Moreover, they continue to use the term “mammal-like reptile”, rather than the more accepted term synapsid, which makes this section appear severely dated. They still use the term “thecodont” to describe the earliest archosaurs that led to dinosaurs, although they at least do say it is an informal term, not one that is formally accepted. The problem with thecodont as a term is that it throws everything with a similar jaw together, whether or not they are related. The bulk of the chapter is a good, but necessarily brief description of the Mesozoic Era, including the position of the continents, the changing climate, and the evolution of plants and animals during this time, focusing of course on the dinosaurs, but not to the exclusion of everything else, which provides the necessary context for dinosaur evolution during this time.

Chapter two is all about movement and tells the story of how dinosaurs went from a lizard-like sprawl to a fully erect posture and the advantages that gave. There is discussion of some of the evidence we have for different gaits and stances, including a lot of discussion about trackways, as well as the diversity in the ways an erect stance has been utilized. The stories of early ideas is an interesting read, although they make one serious error by saying all sauropods had their nostrils on the top of their heads, when in fact they had their noses at the end of their snouts like every other terrestrial animal. I also think they give too much time to the debate over whether or not tyrannosaurs were scavengers or hunters, even though they do eventually come down on the side of hunters, as pretty much every paleontologist does. The tyrannosaur as scavenger debate was getting a lot of press during the time of publication, but it died down pretty quickly, with no one really accepting it anymore, considering there is evidence of active hunting by tyrannosaurs. Go to the Denver Museum of Nature and Science and you will see an edmontosaur with a healed bite taken out of its back.

Chapter three discusses food, how different dinosaurs ate, so one can expect several pictures of skulls and teeth. This chapter gets high marks for discussing current research at the time, such as Emily Rayfield’s work using Finite Element Analysis to determine bite force in several dinosaurs. Criticisms of the chapter include too much credence given to the idea that tyrannosaurs were scavengers which they revisit in this chapter, the discussion of neck posture in sauropods, and missing an important aspect of the tyrannosaur coprolite studies. These criticisms are mostly due to advances since the book was published, not a fault of the authors.  The neck posture study has the problem of not sufficiently allowing for cartilage between the vertebrae, nor the fact that living animals bend their necks farther than allowed by that study on a regular basis. The tyrannosaur coprolite study also found remnants of muscle, which indicates a short digestion time. This is a strong indicator of an endothermic animal. Either that or an animal suffering some serious diarrhea. Finally, the chewing cycle of hadrosaurs is no longer as accepted as it was then. Casey Holliday makes a good case that the bones of the skull thought to move during chewing were really much better bound together in life, the supposed joints more an accommodation of quick growth, not for chewing (sadly, the link to the pdf of the paper in the linked article is no longer valid, but the article provides a good summary of the paper).

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Chapter four is attack and defense. Interestingly, this chapter discusses tyrannosaurs as hunters, ignoring the scavenger discussion of the previous chapter, providing some indication on where the authors fell in that debate. This chapter does a great job of discussing different techniques for combat and predator avoidance. High marks to this chapter for balanced discussion of current research. I particularly liked the discussion about the role of color in camouflage and display. The biggest gripe about this chapter is the presentation of theropods like Troodon as scaly when we know they were covered in feathers. It doesn’t change the discussion in the text, which is still valid and interesting, but it is a flaw in the presentation.

NHMbook

Chapter five is about social organization, a topic not often covered well in books like this and is possibly my favorite chapter in the book. There are some interesting discussions here that will make one think about these animals as living animals within an ecological context. I would note that there is more evidence of group behavior of tyrannosaurs than was known at the time of publication, so they may have been more gregarious than thought then. I would have liked a bit more explicit discussion of the possibility of Deinonychus as opportunistic groups rather than a cohesive pack, but the discussions do a great job of keeping facts that we know and speculation about behaviors.

Chapter six is titled “Living animals”. This chapter gets into the detailed work of anatomy and molecular studies used to figure out how the animals were put together functionally and metabolically, as well as what their anatomical details tell us about behaviors. It serves as a nice introduction to the real work of paleontologists as more than just digging up fossils. It is a nice chapter and a great read. There are a few things that are a bit off, but not much. They discuss the discovery of actual soft tissue reported from a few dinosaur bones, such as proteins, blood cells, and blood vessels. They do not mention, however, that not everyone accepts those discoveries, instead concluding that what was found were more modern bacterial traces and not dinosaur soft tissue. Nevertheless, it is a good inclusion in the chapter. Our understanding of just how many dinosaurs had feathered has also grown dramatically since the book was published. Few people took the idea of a feathered, adult tyrannosaur seriously ten years ago, but we now have evidence some large tyrannosaurs were indeed feathered. They also make determining brain size in dinosaurs sound much easier than it really is because the amount of non-brain material in the cranial cavity varies substantially in animals other than mammals and birds. The evidence of color vision in dinosaurs, on the other hand, is stronger than presented in the book and we can pretty securely state that dinosaurs had not only color vision, but better color vision than we do. The book also uses a picture of a tyrannosaur with ridiculously large olfactory lobes that we now know is wrong. Tyrannosaurs had large olfactory lobes, indicating a good sense of smell, but they weren’t as large as presented in the book. The book devotes a decent chunk of space to the question of thermoregulation, although it is still necessarily brief, which they acknowledge, as it is a complicated discussion. For what space they have, they did a good job. I would say the idea of dinosaurs being endothermic for the most part is more accepted now than at the time of publication with new evidence pushing the debate in that direction.

Chapter seven concerns the mass extinction at the end of the Cretaceous. It does a good job of discussing the extinction event, including what did NOT go extinct, which complicates the picture. The evidence of a massive impact has been firmly established even more so than when the book was published. The role it played and whether it was the sole cause or the giant nail in the coffin, adding to the volcanism and changing climate, is still debated.

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Chapter eight is called “Dinosaurs and people” and is mostly a short history of dinosaur discoveries. Chapter nine discusses what it takes to go from a discovered fossil to an understanding of the life and relationships of the animal in question. Between this chapter and chapter six, the work of paleontologists is given a good accounting and should make for a useful read for any budding paleontologist. What has been added since is a huge increase in technology which has increased data sharing, allowed people to form collaborations easier, and made modeling and experiments much easier, allowing more people to make significant contributions.

The final chapter discusses the evidence that birds are dinosaurs. The book discusses several feathered dinosaurs, but our knowledge of them and the diversity of feathered dinosaurs has grown by orders of magnitude since then. We have even found evidence of melanosomes, subcellular organelles that provide the pigment, which has allowed the determination of color in a few cases. The chapter has a good section on the origin of flight, providing the classic hypotheses, but also includes newer ideas that have greatly added to our understanding of flight, making the old hypotheses incomplete, with portions of both providing a much better answer. The book does state one thing that I would cross out. They state “It seems likely that a simple insulating cover arose first and was later modified for display, signalling, and finally flight.” This is a common belief even among paleontologists, but it is simply wrong. It is highly unlikely that feathers first arose as an insulating cover as the initial stages would have done the exact opposite of providing insulation by increasing surface area without a concurrent increase in insualtion. It is far, far more likely that feathers evolved for display purposes and were then adapted for insulation.

The book ends with a section providing data on several specific dinosaurs, a glossary, suggested sources for further reading, and a useful index.

In summary, the book is a great read. It provides an excellent look at dinosaurs as more than a stamp collection of strange creatures, but as living animals within the context of a real ecosystem.  The book gives a better view of the real work of paleontologists than you will find in almost any other source. There are several places in which the science has advanced, making some specifics here and there in need of updating, but the meat of the book is still solid and provides substantial benefit to interested readers. It provides commentary in a much more thoughtful manner than is found in most other books and will make the reader think about concepts in a way rarely seen. The book shows science as a dynamic, changing field where no matter how many answers you get, there are always more questions and every piece of data requires a reexamination of the answers you already have to see if the answers are still valid. Dinosaur science is not extinct, it is still evolving and you definitely get that feeling here.

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The Very Definition of a Modern Major Researcher

Now that Labor Day has come and gone, everyone should be back to school by now. I have been absent for much of the summer and not posted nearly as much as I had hoped to. I have been working on some projects which I hoped to have up by now, but are still in process. Working two jobs right now while trying to maintain some semblence of a personal life has left me precious little energy to work on Paleoaerie. But hopefully, that should end soon and I will be back to posting on a regular basis.

In the meantime, there are some news and upcoming events I would like to share so you can put them on your calendar.

  1. I have received the audio for my talks at the Clinton Presidential Library. Unfortunately, the video was not successful. So as soon as I get the chance to sync the audio to the powerpoint, I will post it here.
  2. I have joined forces with TIES, the Teacher Institute for Evolutionary Science, sponsored by the Richard Dawkins Foundation for Reason and Science. They have a number of excellent resources on their webpage and will allow an improved opportunity to offer workshops on evolution to teachers and other interested parties. These workshops are designed by teachers for teachers and are aligned with the Next Generation Science Standards. If you are interested in a workshop, please either contact me or Bertha Vasquez, the TIES Director. You can also find them on Facebook and Twitter.TIES-banner-2
  3. I will be appearing at the Forest Heights STEM Academy in Little Rock on Friday, September 11, to discuss how the scientific method is really used by scientists.
  4. I will be appearing at the next quarterly meeting of the Arkansas STEM Coalition meeting on September 25 to talk about TIES and National Fossil Day.
  5. NFD_2015_Oval

    NFD_2015_Oval

    Speaking of National Fossil Day, make sure to put Saturday, October 17th on your calendar. The Museum of Discovery is hosting the second annual National Fossil Day event, even bigger and better than last year. Don’t miss it. National Fossil Day is a part of Earth Science Week, sponsored by the American Geosciences Institute, designed to “help the public gain a better understanding and appreciation for the Earth Sciences and to encourage stewardship of the Earth.”

Now that all the business is out of the way, I will get on with more educational material. In honor of everyone going back to school, I thought I would start a few posts about some definitions that most people generally get wrong. Today, I am going to discuss a few of the types of scientists that study past life.

imagesWhenever a scientist tells people they are an archaeologist or paleontologist, they tend to brace themselves for the almost invariable questions about the other field. In most people’s minds, all the different sciences seem to be interchangeable, with little understanding that just because someone studies the past, they don’t necessarily study everything in the past. I won’t even get into the difference between scientists who study past life and historians. I will leave that for any archaeologists who wish to tackle that issue. I get this question so often that I bought this Tshirt.

Even though we all study past life, there are important differences. Here is a Venn diagram I created that may help explain how they differ.

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As you can see, there are two main divisions in scientists who study past life: those who study humans and those who study everything else.

Anthropologists study humans, so don’t ask them about dinosaurs or mammoths or giant sharks. Don’t bring them a fossil you found. If you find a pottery shard or an arrow head, find an anthropologist. If you found a book, you might also try a historian. Ok, I said I wouldn’t get into this, but maybe just a little bit. Historians deal with written human history. So one might say that historians are a subset of anthropologists, in that they only deal with relatively recent anthropology. Many would also argue that they should not be included at all because they do not approach the endeavor with a scientific approach. While I can see the point, I can also see the point that this would also include many anthropologists, so comes across as sounding like the argument about can bloggers be considered journalists. The correct answer is that it is not as simple as that. But it’s not my field and my view of the topic is strictly as an outsider.

Paleontologists study everything that does not include humans. So please feel free to ask us about extinct organisms, as long as they don’t make pottery or arrow heads.This doesn’t mean to say that every paleontologist studies all extinct organisms. There are innumerable specialities within the field. If you ask a paleoclimatologist to identify a bone, he won’t have a clue what you are talking about. They study past climates, not bones. Just like one wouldn’t ask a podiatrist (foot doctor) to do brain surgery, don’t expect an expert in Pleistocene pollen to help you identify which type of trilobite you have, although I expect they could tell you that you do indeed have a trilobite.

But what do you do if you find a fossil of a hominid, something not quite human, but not quite an ape? That is where paleoanthropologists come in. They deal with that intersection between paleontology and anthropology, where the lines blur into shades of grey. In point of fact, all these terms are arbitrary boundaries and only serve to help us break up the studies into something manageable. Like everything else in nature, we have taken a continuous spectrum and cut it into defined sections to satisfy our need to categorize everything.

Even though there is far more life that is not human than there is that counts as human, for obvious reasons. The study of humans is more discussed than anything else. So while it is not my field, i will attempt to separate the major divisions within anthropology. Anthropologists, as mentioned study anything to do with humans. This can be broken down into two main categories. Physical anthropologists study the biology and evolution of humans. If you have human bones, they are the ones to talk to. Cultural anthropologists study human culture, their behaviors, what they make, how they interact with others. If it’s not a bone, but related to humans, ask a cultural anthropologist.

But what then are archaeologists? Do they not do the same thing as anthropologists? Yes, because they are anthropologists. They are just a subset that happens to be so well known that many people lump archaeologists and anthropologists together as if they are the same thing. But they aren’t, not quite. All archaeologists are anthropologists, but not all anthropologists are archaeologists.

Archaeologists study past human life through physical remains. Thus, they include some of both physical and cultural anthropology. They are the ones to talk to about pottery shards, arrow heads, and the like. Any physical evidence of a preexisting culture could be brought to the attention of an archaeologist. However, anthropologists cover a lot more ground, so to speak. There are cultural anthropologists that study current, existing culture. This is in fact a large field within cultural anthropology. There are even physical anthropologists that study evolutionary changes taking place within humans right now. Neither of these would count as archaeologists though.

Just as in anthropology, as I mentioned earlier, there are several different subspecialties within paleontology. Here is how the University of California Museum of Paleontology breaks it down.

Paleontology is traditionally divided into various subdisciplines:

Micropaleontology:

      Study of generally microscopic fossils, regardless of the group to which they belong.

Paleobotany: Study of fossil plants; traditionally includes the study of fossil algae and fungi in addition to land plants.

Palynology: Study of pollen and spores, both living and fossil, produced by land plants and protists.

Invertebrate Paleontology: Study of invertebrate animal fossils, such as mollusks, echinoderms, and others.

Vertebrate Paleontology: Study of vertebrate fossils, from primitive fishes to mammals.

Human Paleontology (Paleoanthropology): The study of prehistoric human and proto-human fossils.

Taphonomy: Study of the processes of decay, preservation, and the formation of fossils in general.

Ichnology: Study of fossil tracks, trails, and footprints.

Paleoecology: Study of the ecology and climate of the past, as revealed both by fossils and by other methods.

Each one of these can be broken down into even more specific specialties. Paleoecologists can specialize in biogeography, limnology, pedology, tempestology, schlerochronology,and many others. Vertebrate (and invertebrate) paleontologists can specialize in taxonomy, systematics, functional morphology, etc., but I think you get the point. There is far more that can be studied by any individual. paleontology, like any other science, is a team sport.

There are no hard and fast boundaries between these of course. Vertebrate and invertebrate paleontologists can and do study taxonomy, biogeochemistry, paleoecology, and taphonomy, and others all at the same time. Paleontology is highly interdiscplinary and requires knowledge in a lot of different fields. But many scientists tend to spend most of their time in a specific area.

So if you have a question, you will get the most detailed answers from someone in the right specialty. Choose wisely and you will get your questions answered. If you don’t, go to grad school, discover them for yourself and let everyone else know about it.