Category Archives: Dinosaurs

What’s the value of a fossil?

I have the privilege to work as a professional paleontologist. Many people are excited by fossils and beasts from the past, and the media loves to cover new discoveries. Periodically, a friend will ask if I had heard of the latest fossil find being discussed by the media, almost always touted as the latest, the greatest, the biggest, or the best example of whatever. With genuine enthusiasm my friend will ask how thrilled I am about it. While I really appreciate their eagerness for me and my profession, when the fossils were collected by someone hoping to sell them I have to say, no, I am not really excited about the find.

My friend will usually blink a few times, trying to understand how I could feel that way. How can I help them understand why academic paleontologists are not excited by such specimens? Why if I have dedicated my career to learning about life of the past would I not even be interested in seeing such fossils? Wouldn’t all scientists be falling over themselves with glee to see these treasures? No.

The latest example is the so-called Dueling Dinosaurs from Montana, and much has been written about them, a meat-eating and a plant-eating dinosaur found together, promoted as having died in mortal combat. But these fossils are simply the latest example in the long-standing conflict between science and the commercialization of fossils. The key to easily understanding this conflict is to understand the two very different ways of appraising the value of a fossil: commercial and scientific.

We are immersed in the commercial value of things. Everything has a price. All around us in everyday life we see prices placed on goods and services. We are so comfortable making judgments about the monetary value of items we even have game shows like the Price is Right where we compete with each other to do so.

Additionally, we are familiar with collectors of all types. Art collectors, people who collect baseball cards, or old bottles. We occasionally hear of a rare collectable item selling for high prices, and fossils seem like they could be in that same category of potentially valuable collectable items.

“Sues skeleton” by Connie Ma from Chicago, United States of America – Sue, the world’s largest and most complete dinosaur skeleton.Uploaded by FunkMonk. Licensed under CC BY-SA 2.0 via Wikimedia Commons

High-profile fossils have occasionally been valued at very high market values. The Tyrannosaurus “Sue” sold at auction for over 8 million dollars. Recently another similar dinosaur was to be sold for over a million. The sellers of the Dueling Dinosaurs are reported to want 7 to 9 million. And the implication is clear—you can get rich on dinosaurs.

In our market-based society it is easy for non-scientists to think that market value must be the same as scientific value. High-dollar fossils must be worth more to science, right? This equivocation, however, is false.

To appraise the market value of a fossil you have to know what a willing buyer will pay a willing seller under current market conditions.

The scientific value of a fossil is very simply its ability to add to existing knowledge. To appraise the scientific value one needs to know about all the research that has taken place to date, all the specimens currently known to science, and an individual fossil’s potential to tell us something we didn’t already know.

The issue hinges on the fact that for a fossil to have high scientific value we must be extremely confident in the reliability of the information that accompanies it. The commercial collection of fossils is usually driven by other pressures, and unfortunately there are far too many examples where the information valued by scientists is not collected. Or worse, where the information is unreliable or even falsified. Too frequently people looking to sell fossils for large monetary gain collected the fossils illegally, or dishonestly, and then seek to hide those facts from buyers. The temptation of large payoffs is often too great.

From a scientific stand point the value of a fossil is significantly reduced if we do not know, or cannot rely on, certain basic information. Where did the fossil come from? Who collected it? Can we be sure it is one fossil or is it a composite of two or more fossils? Could it be a forgery? Do we have records of the fossil’s context with the surrounding rocks? What did the rocks tell us about the environment in which it was buried? What other fossils were found with it that would give clues to the environment in which it lived? What clues were with the fossil that may have gotten removed during the preparation of the fossil?

The primary “currency” of academic paleontologists is integrity—if our colleagues lose trust in our work and our word we have nothing. So, there is little incentive to deceive or falsify our data or claims, and in fact there is a great potential for career-ending consequences if one is caught being dishonest.

Unfortunately that is not the case for commercial collectors. In a climate where you can sell a fossil for millions of dollars you just need to do that once to be set for life. The integrity and motivations of commercial collectors is then suspect; there are just too many examples of theft, lies, and deceit.

I am not implying anything about the people involved in the Dueling Dinosaurs. Rather, I am saying that the general lack of academic enthusiasm for their fossils is because of past experience. The prices demanded are out of reach of museums and the risk of obtaining false data is just too great. When the next biggest, best, and rarest fossil comes around we must watch their sale with detached sadness, and hope for the best.

Perhaps the Dueling Dinosaurs will end up at a museum, and maybe any questions about the integrity of those fossils can be satisfactorily addressed. Perhaps those fossils will become a conversation piece in someone’s trophy room, and if so they will likely be lost forever to science and by extension to all of us.

Fortunately, the public lands of the United States are available to researchers, where the ownership of fossils is clearly established to be the public, and commercial value plays no role. There, and on private land generously made available by land owners, scientists and genuine amateur enthusiasts can collect, study, and learn about the past with fossils that can advance our knowledge.

For the landowners, field collectors, and the people involved in buying and selling fossils I guess I have to say I don’t blame you for your interest. Fossils are cool. And if you make a million dollars, I guess good for you. However, understand that the commercial collection and sale of fossils has virtually nothing to do with the science of paleontology. The only commonality between the two is the fossils, and whereas commercial fossils may have a high market value, their scientific value is severely compromised.

Two dinosaurs become one

Earlier this year a paper was published (Scannella and Horner 2010) on one of the most well-known dinosaurs of the Late Cretaceous, Triceratops, updating our understanding of not only this dinosaur species, but also maybe influencing our view of many other dinosaur species as well.

Triceratops as mounted at the Carnegie Museum of Natural History

Triceratops was first described in 1889 by O. C. Marsh, and has become one of the best represented dinosaur species in terms of numbers of fossils recovered. Their remains are very common in the Hell Creek Formation of Montana and the Dakotas. And, Triceratops has been known by practically every kid for the last 100 years, being well represented in dinosaur movies and dinosaur toys the world over.

Triceratops is best known for its three horns and neck frill of bone. Torosaurus, another dinosaur that is obviously related to Triceratops because of its similar appearance, was also first named by Marsh in 1891. It is found in the same geologic units in the same region, but is much less commonly found. Torosaurus was much larger than Triceratops, and had large openings in the neck frill, and its horns pointed more anteriorly.

So, for over 100 years paleontologists thought there were at least two species of horned dinosaurs in these beds. But scientific understanding makes progress. In the early “bone rush” days of the nineteenth century the game was naming new species. Today, there is a trend of relooking at those species to see if they are in fact different.

"Torosaurus" mount at the Milwaulkee Museum, now should be called Triceratops.

This is where the new study comes in. The authors examined Triceratops and Torosaurus and questioned whether they might not be the same species, but at different life stages. It has become apparent that individuals of a species can change a great deal over their lifetimes. A newborn human does not look much like an adult in body proportions, for example. If past species also changed significantly over their lifetimes, the different stages could easily be mistaken as completely different species. And that seems to be the case here.

By looking closely at the trends of skull shape and indicators of maturity, Scannella and Horner believe that in fact Torosaurus individuals are older and more mature individuals of Triceratops. This means that later in their development individual Triceratops specimens changed significantly as they reached maturity, developing the large openings in the neck frill and increasing in overall size.

The implications for other dinosaur species are clear. If individuals can change dramatically during their lifetimes as they mature, perhaps there are many named dinosaurs that are not truly different and unique species, and we need to match youngsters with adults. No doubt this will keep paleontologists busy for the next 100 years.

And in case you are worried, the name Triceratops will remain, since it was the first name given to the species that we now realize includes those individuals that one were called “Torosaurus.” So, despite some headlines Triceratops did (and still does) exist!

Scannella, J. B., and J. R. Horner. 2010. Torosaurus Marsh, 1891, is Triceratops Marsh, 1889 (Ceratopsidae: Chasmosaurinae): synonymy through ontogeny. Journal of Vertebrate Paleontology 30(4):1157 – 1168.

I am a paleontologist

I love the science of paleontology for many reasons. The science combines so many other areas of study into one bundle, such as geology, biology, functional morphology, evolution, stratigraphy, and systematics.

Not only that, dinosaurs and other prehistoric animals are just fun! And being fun, paleontology is a great way to introduce people to science in an engaging way. How many young people start their interest in science by learning about dinosaurs, and say they want to be a paleontologist when they grow up–a bunch!

Well, someone shared this video with me and I love sharing it with you. Enjoy! (you may need to scroll down).

Why dinosaurs are not extinct

In the twenty plus years I have been involved in paleontology I have been witness to a revolution within science. The revolution has been quiet, not noticed by most of the public. Like any good revolution, the battles of this revolution took place between two camps, the “traditionalists” and the “radicals” who were out to change things. And this shift is illustrative of how science as a whole moves from one way of understanding to a brand new way of looking at the world. It is, in fact, a paradigm shift that has profoundly changed biology and paleontology forever.

At issue is how we explore and classify the relationships of all living things. The traditional view, the one that I was taught as a young student, was the classification of living things into the taxonomy originally begun by Carl Linnaeus. This system started with a group, and then sought to put things into the group. For example, one can make the observation that animals that look like “dogs” could be grouped together, so you would start with the idea of a dog-group and look for animals that should be included.

You might put foxes, wolves, domestic dogs into the group, and call it the dog family. You might also note that “cats” could likewise be grouped, and do the same thing, creating a cat family. In this view, the families were equal in rank—and there could be no overlap. An animal would be included in only one of the equal-ranked families. Any animal was included in only one class, for example Amphibia, Reptilia, Aves, or Mammalia.

The equal-ranked heirarchy of classifications worked well enough when we mainly were concerned with modern animals. Clearly, birds look different than mammals and reptiles, so it seemed evident they belonged in their own class. But this classification scheme, however well it served us as a place to start, is myopic about how evolution actually operates—how organisms actually evolve. This is understandable since it was started 100 years before evolution as a theory was established.

In trying to shoehorn life into the system, we repeatedly ran into problems as we expanded our knowledge of the diversity of living things and our understanding that the history of life is a complex branching bush. We knew that early tetrapods (organisms with four limbs) gave rise to the early amphibians that crawled out on land, and that they in turn evolved into reptiles, mammals and birds. But despite this branching within tetrapods, the class ranks were forced to be exclusive, so somewhere in evolutionary history was an “amphibian” that had to become a “reptile,” and a “reptile” that had to become a “bird.”

The many transitional forms in the fossil record increasing became impossible to classify. These intermediate animals had to be forced into one class or another. Increasingly, it became evident that many times the criteria used to put an organism into one class were the whims of an individual scientist, and another equally qualified expert with different opinions might place the same animal in a different class with equal validity.

The origin of birds was for a long time a great mystery to paleontologists. Birds are a pretty unique and specialized group, and while we knew that they originated from reptiles somehow, exactly how and when was unclear. One early paleontologist noted that dinosaurs had many features in common with birds, but the early concepts of what dinosaurs were like distracted most scientists from comparing them too closely. After all, the common conception of dinosaurs was as big, lumbering, dim-witted, swamp-dwelling beasts. The bird ancestor must have been light, fast moving, and energetic.

However, dinosaur research over the last thirty years has completely changed our view of them. Evidence from many lines, including things like footprints and the cellular structure of the bones, all point to dinosaurs as being very dynamic creatures. With this new view, the notion that birds were linked to dinosaurs became clear too. Now, we have dinosaur fossils with feathers, and birds with teeth and dinosaur tails to attest to their close relationships. In fact, birds are most closely related to the meat-eating raptor-like dinosaurs of Jurassic Park fame.

To go along with the revolution in our view of dinosaurs was that revolution in science that I mentioned above–the emergence of a new way to understand the interrelationships of life on Earth. This new model accommodated the myriad branching events that life actually experienced in order to produce the great variety of living things. So, instead of starting with a conception of the group and looking for members, this new concept looked at the branching patterns evident in life, and then sought to apply names.

Below is an illustration of the branching pattern of selected tetrapods, those vertebrates with four well developed limbs. As the first tetrapods gave rise to new and different groups, the branches split off. An early tetrapod gave rise to amphibians and the other animals above it on the chart (mammals, turtles, etc.). A later tetrapod developed traits related to the production of eggs and young that we recognize as the Amniota. Some of those early amniotes went off on an evolutionary trajectory that we can recognize as being the early mammals, and all the diversity that resulted from them. And so it goes up along the branches.

Branching pattern of the tetrapods, mostly the land vertebrates

We now explore the branches and can apply names to the groups that we find to be meaningful. For example, in the illustration below we can call everything in the box a reptile. Note that it includes things that used to be called reptiles, turtles, lizards, snakes, crocodiles, and dinosaurs, but now also includes birds.

Group that includes all the reptiles

Likewise, if we draw a line around the dinosaurs, they also include the birds. This view of life tells a more complete evolutionary history and retains the branches, letting the animals “fall where they will.” We do not pull birds out of their relationships and give them special consideration. Instead of birds being equal in rank with reptiles, they are included among them. This upsets the tradition that being a bird is somehow equally important to being a reptile, but better reflects the reality of descent, without forcing nature into earlier human conventions of naming and grouping. Of course, birds are a group within their own right, and we could zoom in to explore their branching pattern, but it does not change the group to which they belong.

Group of dinosaurs

This leads to another startling statement. Below I have highlighted the groups that are extant (still around today).

Groups of tetrapods that are alive today (extant)

Because of our grouping scheme, birds are included in the dinosaur group, so dinosaurs are not really extinct! They live among us today flitting about, singing their mating songs in the trees. It is funny how things can change in science. Twenty years ago scientists would have told you the dinosaurs were all extinct, and today we say the opposite. I love scientific progress–it can be so startling.

Science in dinosaur movies: Jurassic Park, then and now

The 1993 movie Jurassic Park, based on the book by Michael Crichton and directed by Steven Spielberg, is seen by most enthusiasts as the best dinosaur movie that Hollywood has produced. It set a high-water mark in the genre for many reasons: it took dinosaurs seriously as a topic, and did not portray the animals simply as ridiculous extras; and the movie was amazing for its visual effects. For any movie from Jurassic Park onward, your dinosaurs had better look real, scary, and believable.

Jurassic Park was also important in that it showed dinosaurs more or less accurately, consulting with real paleontologists in its making, and working to utilize the latest and greatest views on dinosaurs. This is not to say that they did not put in a Hollywood spin, or as I have called it in the past, “Spielbergize” some of the dinosaurs, but as a paleontologist I could really see that the ideas were not completely out of the blue. In fact, Spielberg foreshadowed some of the findings about dinosaurs that were to come.

I want to review some of the key features of Jurassic Park as they were thought of in Hollywood in 1993 and compare that with the state of the art today.

Dinosaur DNA

The entire premise of Jurassic Park is that DNA from extinct species was collected and cloned in order to bring the animals back to life. Are we any closer to being able to do this? Well, not really.

The complete DNA code of any single species is very long and complex, and it is very unlikely that any DNA molecule will survive intact for millions of years. We cannot even clone species that are modern or recently extinct with much success, and we have access to their DNA. The technical difficulties of getting DNA intact, knowing how to put that DNA together on chromosomes, knowing how to trigger the genes on the chromosomes to turn on and off during development, means that even if we could somehow get a complete dinosaur DNA sequence, we could not make a living animal.

However, there have been some amazing advances in molecular paleontology, where protein fragments and amino acids have been shown to be able to survive within fossil bone for an extraordinarily long time, much to the surprise of scientists who assumed that fossilization would destroy the tissues at the molecular level. Making predictions is difficult, especially about the future. Who knows what discoveries await us, but for now, the current best answer is that we will never be able to clone a dinosaur. (See Mammoth protein designed to be cool for more on molecular paleontology).

Excavation Scene

Early in the movie we are treated to a scene of a paleontology excavation as modern paleontologists dig into the past to understand dinosaurs. As with any profession, portrayal in a movie is not often close to reality. Cop movies do not realistically show what it is like to be a cop. Lawyer and doctor movies stretch the true on those professions, and the excavation scene was the one where me and my professional colleagues got a good laugh.

We see the field crew effortlessly dusting sand away from crisp fossil bone. We see the team firing off seismic charges to send waves into the rock to visualize complete dinosaur skeletons underground, just waiting to be effortlessly dug out. Oh boy. This is so far from the truth.

We cannot simply use a type of remote sensing technology to visualize unexposed fossils, however there are a few technologies that people have tried to use. Sometimes the minerals that fill fossil bone have a higher concentration of radioactive elements, and so mapping the concentration of radioactivity over a site has helped to locate concentrations of fossils in those cases. There is a technology called ground-penetrating radar which under certain circumstances could be applied to fossils, but its use is limited. The main problem with both of these techniques is that to find fossils underground, you have to be able to tell them apart from the surrounding rock, and too often the fossils are very similar to the rock that encases them.

Fossils are still found the old fashioned way—by looking for bones weathering out on the surface, and digging around them in hopes that something more is there.

And of course, it is not as simple as dusting them off. Fossils are often enclosed in a hard matrix of rock, which can take many hours of tedious labor to remove. Frequently in the field the fossils are exposed enough to understand how they are laid out, and then removed in giant blocks to be worked on back in the museum lab for the next several years.

Velociraptor

The undeniable stars of the movie were the “raptors.” As shown, they were cunning and relentless killers, bent upon creating havoc for their human character counterparts. In the movie, the velociraptors were shown to be about as tall as an adult human and perhaps 12 feet long nose to tail. That was an exaggeration to say the least.

Real velociraptors have been excavated in Central Asia, and are not known from North America as fossils. However, there are Velociraptor relatives known from this continent. But in life, real velociraptors were only about half the size shown in the movie, maybe the size of a mid-sized dog.

However, Spielberg did not know it, but his velociraptors did not have to be exaggerated in size if he had just said that they were a dinosaur species that was discovered in 1991, and named in 1993—Utahraptor (Kirkland et al. 1993). The same year that Jurassic Park was released also saw the emergence of Utahraptor, a dinosaur that much better fits the dinosaur shown on film. It was discovered in North America, as was suggested for Velociraptor in the movie, and was the size of the animals shown in the film. So, in a way, Spielberg was showing a real dinosaur, just not the one he thought.

Tyrannosaurs Running

It might be a close call as to which was more popular in the movie, Velociraptor or the seminal favorite dinosaur Tyrannosaurus. Who did not thrill to see the giant animal trash Jeeps, eat lawyers, and run amuck? In a harrowing scene, tourists of Jurassic Park are chased at top speed by the Tyrannosaurus and only just manage to escape in their vehicle.

Could Tyrannosaurus almost outrun a Jeep? Well, likely not.

Large animals today do not run well. The heavier an animal is, the more force there is on the animal’s joints and bones, and running compounds the effects of those forces. Modern elephants cannot run, but rather trot. They can move quickly, but they are too large to achieve a full-scale run.

How to kill Tyrannosaurus, from Farlow, Smith, and Robinson, Journal of Vertebrate Paleontology, vol 15(4).

Likewise, tyrannosaurs were very large and heavy animals, and there are physical constraints based upon the strength of their bones and joints. And unlike an elephant, Tyrannosaurus supported all their weight upon two legs, teeter-tottered over their hips. Running would have placed tremendous stresses on the hip joint.

Also, unlike an elephant, the large head of a tyrannosaur was extended out over the ground, as much as 15 feet above the surface, and they did not have forelimbs of any size to speak of. This means that if they did get up to a significant running speed and were to stumble, their heads would fall with great force to the ground without any way to break the fall. In short, if they did run and fall they would bash their brains out on the ground. Running, in this case, would be fatal.

Venomous dinosaurs

In Jurassic Park, the dinosaur Dilophosaurus was portrayed as being able to spit blinding venom into its victim’s eyes. The suggestion that a dinosaur was venomous was groundbreaking. Earlier this year there was a report of the discovery of a venom delivery system in a raptor dinosaur, Sinornithosaurus (Gong et al. 2010), seeming to once again make Spielberg a paleontological prognosticator.

However, it does not seem likely that the interpretation of Sinornithosaurus as being venomous will stand up to further scrutiny. Secondary investigations of the fossils suggest that characters which were viewed as supporting a venom delivery system are actually not what they were first thought (Gianechini and Agnolin 2010), so it looks like we still have to wait to find a venomous dinosaur, much less one that can spit!

Jurassic Park stands as one of the greatest dinosaur movies. From a paleontology stand point, while the movie is fiction several interesting propositions were shown, and this is, after all, what drives our curiosity to explore.

Dinosaur movies at Amazon

References:

Gianechini, F. A., and F. L. Agnolin. 2010. A reassessment of the purported venom delivery system of the bird-like raptor Sinornithosaurus. Paläontologische Zeitschrift.

Gong, E., L. D. Martin, D. A. Burnham, and A. R. Falk. 2010. The birdlike raptor Sinornithosaurus was venomous. Proceedings of the National Academy of Sciences 107(2):766-768.

Kirkland, J. I., R. Gaston, and D. Burge. 1993. A large dromaeosaur (Theropoda) from the Lower Cretaceous of eastern Utah. Hunteria 2(10):1-16.

Boneblogger: Science and the outdoors

Exploring the natural world