Category Archives: Science

A Paleontologist’s Critique of Jurassic World

I have written here before about being a professional paleontologist. As such, I have to say I was not enthusiastically looking forward to the newest installment of the Jurassic Park franchise, Jurassic World. In fact, I expected to hate it.

From the previews the story line was hinted at: another park with dinosaurs, many unrealistic reconstructions of the fossil animals they were supposed to portray, a new genetically engineered dinosaur, and packs of raptors being led against the new bad dino by a motorcycle-riding hero (a paleontologist, we thought surely). Oh boy, we thought collectively. A “paleontologist” leading a pack of trained raptors against other dinosaurs to defend humanity. Proving to doubters that his rag-tag team of raptors could be led and become the heroes he knew them to be. What a cliché and a stinker of a movie this will be.

"Jurassic World poster" by Source (WP:NFCC#4). Licensed under Fair use of copyrighted material in the context of Jurassic World">Fair use via Wikipedia.

Jurassic World poster” by Source (WP:NFCC#4). Licensed under Fair use via Wikipedia.

But I went, as I knew I had to be culturally literate about what 10 year olds would be asking me for the next dozen years. Things like, what will it be like to be the alpha raptor?

And to my surprise, I didn’t hate the movie. I actually liked it. Here is why: there is not a single paleontologist in the entire thing!

This movie took strides to move away from the science of paleontology altogether. Sure, the park has big dinosaurs, but none of the dinosaurs they created were “real.” Even in the original park, they pointed out, all the dinosaurs had additional genetics to make them viable animals, so they were always facsimiles of dinosaurs anyway. And now in Jurassic World they are going all out and creating attractions, not reality.

In the past Jurassic Park movies to one degree or another there was an attempt to conform to current knowledge of dinosaur biology. And by walking the line between science and movie making they repeatedly failed to satisfy the picky scientists. “Velociraptor was not that big.” “Most of the dinosaurs are from the Cretaceous, not the Jurassic.” “The T. rex should have feathers, why didn’t they put feathers on them!”

But in Jurassic World they didn’t need a single cartoonish paleontologist character to advise them on how the animals looked or behaved (“She cannot see you if you don’t move.” Yeah, right), or espousing the latest dinosaur lore. It is as if the movie makers were saying “Get off our backs you paleontologists!”

chris-pratt-velociraptor-jurassic-worldThere is no real pretense to be scientific. Hybrid dinosaurs? We are just making them up as attractions, so no problem. Using packs of dinosaurs led by a human against other dinosaurs. Sure, why not. The evil characters were the marketers and the genetic engineers making things up for profit, and the ever-present corporation looking to weaponize something. No paleontologists needed.

And Chris Pratt’s character, Owen Grady, the one who looked suspiciously like the love child between Indiana Jones and, well, a paleontologist version of Indiana Jones…not a paleontologist. OK fine, he can train all the wild animals he wants to.

The franchise may never die, and now they can continue to make thrilling movies with spectacular special effects unrestricted by scientific sour grapes. They can concoct all the crazy, wild, mean, giant critters they want, and I for one will not get a professional (dinosaur) feather ruffled. Just don’t pretend that they represent real prehistoric critters.

Finally, paleontologists have been freed from “the Park.”

*I cannot help myself. Mosasaurs were not that big, and pterosaurs could not have carried off full grown women. There, I said it.

jurassic-world-trailer

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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 - http://commons.wikimedia.org/wiki/File:Sues_skeleton.jpg#mediaviewer/File:Sues_skeleton.jpg

“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.

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Rare Meteorite from Mars is Donated to Science

The Natural History Museum in London has recently become the proud owner of the largest piece of the Tissint Martian meteorite. The new addition is now the largest piece of meteorite held in the prestigious museum, weighing in at 1.1kg. The museum is delighted with the donation, but do not know who to thank because the donor has decided to stay anonymous. The piece of meteorite would not have come cheap, and is thought to have cost much more than a Mediterranean cruise or a flashy new sports car.

Scientists hope to find answers to questions about the Red Planet, like what its atmosphere used to be like and whether life could have once flourished on the planet. Dr. Caroline Smith works at the Natural History Museum, and has said the Tissint meteorite is the, “most important meteorite to have landed on Planet Earth in the last 100 years”.

How the Martian Meteorite Ended up at the Natural Science Museum

Last year in July, eyewitnesses in Morocco heard two loud sonic booms as a bright light sped towards the ground leaving a distinctive trail behind it. That bright light was a meteorite, which entered Earth’s atmosphere and broke up into smaller pieces before landing in a desert in southern Morocco. The pieces of rare Martian meteorite, called Tissint, were quickly searched for and collected up before the Earth’s atmosphere could contaminate them too much.

A man named Darryl Pitt, of the Macovich Collection in New York City, heard about the meteorite landing and set out to track a piece down. Rumors spread about it being retrieved and Mr. Pitt frantically searched for people possessing the alien rock. He almost gave up his quest, but then a phone call out of the blue lead him straight to the largest piece recovered. Mr. Pitt purchased the meteorite on behalf of an anonymous benefactor and then donated it to the Natural History Museum in London.

Details of how much the rare space rock actually cost have not been revealed, and the donor wishes for their identity to be kept private. But a spokesperson from Sotheby’s auction house in London has said that meteorites had previously sold for sums between £10,000 and £20,000, but the origin of the meteorite makes a lot of difference, as does its size. It might be the case that the Martian meteorite in question reached a price similar to the Moon Rock sold at Sotheby’s in 1993, which reached a staggering £250,000.

Why the Tissint meteorite is so rare

There have only been four recorded meteorites from Mars landing on Earth, and the last most recent one landing in Nigeria 50 years ago, in 1962. The three other occasions where in 1911, 1865, and 1815. In the last fifty years technology has developed so rapidly that there are new ways to analyze Martian rock, and scientists are excited at the prospect of studying a piece of the Tissint meteorite. Another reason that this particular meteorite is significant compared to earlier landings is the short amount of time between landing and collection. They landed in a dry area of desert, so contamination from the earth’s environment and organisms has been minimal.

Out of the 41,000 known meteorites in the global science community, only 61 of them originate from Mars, only 0.15% of all meteorites. Material from Mars has never been able to be transported back to Earth by human efforts, although this may happen in the next decade. Even so, the process of collecting rocks from Mars and bringing them back here would costs billions of dollars. So having them blasted from the surface of Mars and land on Earth is much easier, but it doesn’t happen often.

What scientists hope to find out from the meteorite

It has already been estimated that the Tissint meteorite was ejected from the surface of Mars approximately 600,000 to 17 million years ago. Scientists hope to be able to glean information about the history of the Red Planet, and maybe gain evidence on whether life existed on Mars in the past.

Further analysis will look at the exact chemistry of the rock, to see what elements it is made of. In particular they will see if any minerals that form when water is present are in the rock, and if it contains molecules rich in carbon. If these things are found, they would provide evidence that there once was life on Mars.

Knowing exactly what secrets the rock holds about the planet nearest to earth is some time away at the moment, but the investigation has begun. Let’s hope this donation inspires other people to help science unravel the many mysteries of the universe.

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Short primer on planning for and attending a professional meeting

I have been very fortunate over the years to have attended many professional meetings across several disciplines, and have learned some tricks over the years for successful meeting attendance. If you are thinking about attending your first meeting hopefully some of these insights will make your meeting experience more productive.

How do you find out about meetings?

If you are student starting a new career path, find out what the professional organizations are for your subject. Join the organization(s) as soon as you can, even as a student. Organizations usually have reduced student dues. It is never too early to begin participating in the field. Almost all organizations have a regular meeting. Some organizations are so large they may have sectional meetings as well as an annual meeting. The sectional meetings might be for a region of the country.

It is very common for the organization to have a special early registration rate, and you can save a little money if you are able to preregister. This allows the planners of the meeting to know how many people to expect, and to get accurate counts for any corporate catering needs. This is one of the hardest areas for planners to project as they don’t want to spend too much money on food, but they don’t want a riot of participants when they run out of coffee and donuts. It does not matter which profession it is, people get hostile when they run out of coffee!

Travel arrangements

Meetings are almost always somewhere else, which is one of their charms—being able to go to a new city, or at least getting out of town. But it does mean you will need to make travel arrangements, and of course the earlier you can do so the better.

Flying is common. If you have not flown recently, be aware that increased security restrictions have changed the experience forever. Also, airlines are now charging you for everything, including having checked and carryon baggage. Don’t forget to include these miscellaneous fees in your budget planning.

There are also some tricks to being prepared for the security screening. Check the restrictions on what you can have in your carryon, and of course avoid anything that will cause them to hold you up. If you take your computer, be sure to pack it at the top of your carryon stuff so you can pull it right out for the screening. Wear slip-on shoes if you can, or at least ones that are easy to tie. Do not have anything in your pockets. Put your cell phone and pocket change in a pocket of your carryon bag so you don’t have to mess with it at screening. Don’t wear a belt if possible, or put it in your carryon and put it on after the screening process. These simple things will help you waltz through the screening with minimal hassle.

Don’t be afraid to check your bags. Despite the horror stories you hear, most baggage handling systems are really amazingly good, and having flown a lot I have rarely had an issue with delayed baggage. Besides, when the bag is delayed, the airline will usually have it delivered to your hotel, so you are typically only inconvenienced for a day or so. Do carry on essential prescriptions and contact supplies or other things you really cannot do without. Being flexible and congenial during unexpected travel snafus will make the experience better for you and everyone else.

However, and this is a big red HOWEVER, if you are presenting at the conference, do not put your presentation in your checked luggage. More than once at a meeting I have seen some poor soul have to stand up and instead of presenting their latest and greatest bit of wisdom, have to say they lost the presentation en route. Not good.

An oral presentation today usually involves a PowerPoint show. This is easy enough to carry on your computer or a memory stick in your carryon. Most poster presentations today are printed out on a large format printer on one of more large sheets of paper. Place them in a cardboard tube and carry it on with you. Even folding it if necessary is better than not having it when you need it. I have also seen people design their poster layout using multiple sheets of regular typing paper arranged in a patch-work style. This way they just carry the ten pages they need for their presentation in a simple folder.

Lodging

Happy geeks at a professional meeting

Happy geeks at a professional meeting

The meeting will likely be at a large conference hotel, and often there is some special rate for attendees at the hotel. Sometimes the organizers will also contact several motels in the area and arrange special rates with them too. My strong advice—stay in the conference hotel. It is often a bit more expensive, but I have found for the convenience it is almost always worth it. It is so nice to be able to pop up to your room if you need to during the day, or to just wake and go to the first session without hassling with fighting morning traffic and parking. It is very common to share a room with a friend, which helps keep the cost down, and if you are willing, you can get a lot of students in one room. Make reservations early as the conference hotel often fills up first.

What to wear

This varies a great deal by profession so you have to know your own field. In general, wear things that are as comfortable as possible. Do you need a dress suit or can you get by with jeans and a t-shirt? I usually see both at any given meeting. Personally, I take “business casual” clothes that are easy to pack. I may pack a tie for the banquet dinner, maybe a sport coat, but less is more, so don’t overdo it.

One nice thing about a sport coat or a sweater is that often the meeting rooms are super-chilled with air conditioning, so having a few things to layer can make you more comfortable.

Most important is to have comfortable shoes. Leave the dress shoes at home, or plan only to wear them for the more formal events. Most of the days are spent walking around the vast conference center, and most evenings are spent standing around talking. Your feet will take a beating, so come prepared.

Registration

When you arrive at the meeting venue, look for the registration tables. Meeting organizers will have a place for attendees to check in and pick up meeting materials. Usually you will get a name tag that marks you as an attendee, maybe some meal tickets, information about the community and area attractions, and a conference schedule and map. Become familiar with this information as soon as you can.

Sessions

Typical presentation set up.

Typical presentation set up.

Most meetings have sessions, both oral and poster. There will likely be concurrent sessions, that is, talks given at the same time in several rooms. The organizers will try and group similar talks into blocks so if there is a topic you particularly want to learn about the talks are all in one place. However, depending upon your interests, you likely will have to move from room to room between talks to catch what you want to see. I like to find the rooms where the sessions will be held as early as I can so I can begin to learn how to move between them. At first it may seem awkward, but before long you will know the conference center well.

As stated, the oral presentations are almost always PowerPoint these days. Larger rooms may have two projector systems set up at different front corners of the room, both showing the same images so you can see from more places in the room. I like to try and sit on the side with the speaker’s podium. Almost always when they speak they make reference to the slides with a laser pointer and so being able to see where they are pointing on the screen can make that easier.

I like to sit as far up front as I can. It is easier to see. However, do think about your “plan of attack” a bit and be considerate of other attendees. If you are just coming into a room with sessions going on, or you know that after this talk you are going to go to another session, sit where you will disturb fewer people. People do come and go all the time and that is OK. Also for this reason I like to sit on the end of a row if possible. It makes leaving easier and more discrete.

If the meeting is well run the session leaders will work hard to keep to the schedule. Usually talks are in 15 minute blocks, and to keep the multiple sessions in sync is difficult. Speakers who are allowed to go over time throw off that session’s timing, and it can be frustrating to attendees who are trying to move between sessions.

This is an important note for speakers too. If you are giving a presentation, work hard ahead of time to fit it into the time slot. It can be very difficult to convey all you want to talk about in such a limited time, but it does not look good for you when the session moderator tells you your time is up and you are not all the way through. Plan ahead and practice your talk several times to get the timing down. A rule of thumb is that you can usually cover about one slide of information in a minute, so for a ten minute talk with five minutes of questions (a typical format) you can only get in about 10-15 slides max. Practice.

Poster sessions are becoming more and more popular at larger meetings. There are only so many speaking slots available in any given meeting, so presenting information in a poster session is a way of fitting in many more presentations. There is often a designated time to view posters and for the authors to be present. Look at the schedule of presentations and earmark those you really want to see ahead of time. An added advantage of the poster session is the author is present for you to informally visit with. This allows for a one-on-one exchange of information that you do not get in the oral presentations.

Also, if you are presenting a poster, bring along a small package of push pins, Velcro stick-on tabs, markers, note cards, masking and scotch tape, and similar items. You are often not really sure when you go to hang your poster what you will need. Sometimes the organizers have been very thorough and provide you everything, but more than once I have shown up and not been able to hang a poster on the wall. Being prepared will save you, and frequently other poster presenters around you, and make your set up a snap.

After you have seen those posters you have targeted to see, don’t forget to wander around the others. Not infrequently, the posters I thought I really wanted to see are a bit disappointing, but a title that I thought would be uninteresting turns out to be amazing. Be open to these kinds of experiences.

Also study the various poster presentations for effectiveness for planning your own future posters. My suggestions are to keep your design simple. It is easy, and tempting, with easy-to-use software to “over design” your poster and make it so cluttered with information and graphics that it is hard to follow. A large part of making a good presentation is knowing how to communicate in a graphic medium, so you might even refer to books on graphic design guidelines. Provide clear section headings in a logical sequence. Make sure to use large fonts for easy readability. As a rule, do not make a “textbook on the wall” by making a lot of long text blocks. Most will never read it. Pictures, graphs, and charts tell your story much better generally. Plus, you will be there to help provide commentary when needed, so keep that in mind.

Vendors

Often a highlight of the meeting is the vendors. Conference organizers will invite companies that provide services to the profession to set up display booths and sell their materials. Sometimes there are conference specials so you can get supplies at a discount. Books are a weakness of mine, and publishers come out in force to professional meetings. It is another good reason for packing light at home, because you will be bringing more back with you than you left with!

Social events

Banquet at a typical professional meeting

Banquet at a typical professional meeting

Conference organizers will likely plan some kind of social event for most evenings of the conference. Frequently there is some sort of snack food there, chips and cheese maybe, and drinks. Most often it is a pay-as-you-go bar, but you may have been provided with drinks tickets as part of your registration. Sometimes soft drinks are free, so just read your conference materials to see what the arrangements are. Frequently the snacks provided are not really enough for a meal, so you may need to hit a downtown restaurant with friends too. I personally really enjoy trying new foods and take in unusual restaurants whenever I can.

These social events are often the most important part of the conference. They are a time for you to catch up with old friends, to meet new ones, and to really talk with your colleagues about trends in your profession. Plan to go to all of them. Remember however to pace yourself. It will be very fun to stay up late tonight, but there are more sessions tomorrow morning. You will have spent a lot of money to come, you want to make the most of it, and you know your body and its resting needs best, so plan your resting times accordingly.

Budget

How much will going to a meeting cost? This is of course not a simple question to answer as tastes in travel, dining style, and purchases of professional materials, all varies by person. Do you like to travel comfortably or are you satisfied with cut-rate?

For a professional attendee traveling to a conference alone, a typical budget for a five-day conference might look like this:

Travel: $600 for airfare
Lodging: $350 for 5 days if room is split with a roommate. Double cost if rooming alone
Food: $180
Registration: $300
Other: $300 Might include ground transportation, books, conference t-shirts, etc.

In my experience, it costs approximately $1,000-$1,700 to attend. You can go less expensively, if you pile a lot of students in a van, pay student registration, and squeeze them into a cheap motel, for example, but this is a good round estimate.

I have never regretted going to a professional meeting. I always return tired, but with a renewed excitement about my profession. I am always inspired by my colleagues and frequently have new ideas I am eager to apply. The challenge is maintaining that momentum when you do come “back to reality” and face the day-to-day tasks again. It can be a good idea to keep a journal of your meeting experience to review when you get home, to help remind you of the excitement you felt with new ideas. Hopefully, that is enough to carry you forward for another year, when you can turn around and do it all again.

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The largest pterosaurs have not been grounded yet

In one post (New evidence on the size of pterosaurs) we explored the study by Henderson (2010) in which he modeled pterosaur body forms to generate estimates of body mass. He modeled different areas of the body separately, applying various densities to the different body sections to calculate his masses. His results suggested that the largest pterosaurs like Pteranodon (wing span of 17.5 feet) and Anhanguera (wingspan 13.5 feet) weighed about as much as the heaviest flying birds (41 and 14 pounds respectively). He reasoned that birds represent a reasonable analogy for flying limits in vertebrates, so this range of masses could represent the upper limit of being able to have powered flight in vertebrates.

His results for the giant pterosaur Quetzalcoatlus were astonishing. His calculations suggest that this animal weighed in at 1200 pounds, with a wingspan of almost 37 feet. After discussing various ways to interpret this result, Henderson suggested that maybe these truly giant animals did not fly at all, but were secondarily terrestrial. This evolutionary track can be found among the birds with giants like ostriches and emus growing large and losing the ability to fly.

The giant pterosaur Quetzalcoatlus northropi compared to a modern giraffe. Illustration by Mark Witton.

The giant pterosaur Quetzalcoatlus northropi compared to a modern giraffe. Illustration by Mark Witton.

Henderson’s work and conclusions was challenged by Witton and Habib (2010). Their criticisms involve several arguments. First, they suggest that birds may not be the best models for flight capacity, and that wing structure, overall anatomy, and launch mechanics were very different in pterosaurs. If so, then using birds as models for flight requirements and limitations in pterosaurs could significantly skew the results.

The heart of the arguments of Witton and Habib are the estimates of wingspan and mass suggested previously for pterosaurs. They note that relatively modest difference in wingspan calculations could have dramatic implications for calculations of mass. They state that mass estimates for a pterosaur with a 43 foot wingspan would be almost twice the estimate for a pterosaur with a 33 foot wingspan. Their assessment of the fossil material suggests that no pterosaurs had a wingspan of greater than 33-36 feet.

Likewise, Witton and Habib are critical of the body shape models used by Henderson for Quetzalcoatlus, arguing that his estimates of body size were too large, and were responsible for the very high mass values he obtained. Combined with Witton and Habib’s wingspan estimates, they calculate a body mass for Quetzalcoatlus of about 440 pounds, about one third the value of Henderson.

All of this discussion about wingspans and weights teases us with the question we really want to know—did the largest winged animals ever known actually fly? Could we have looked up into the Mesozoic skies and seen an animal flying overhead with a 34 foot wingspan and weighing as much as a tiger?

The problem, as is often the case in paleontology, is a lack of fossil material. The preserved material of these large pterosaurs is very fragmentary, and this significantly impacts our ability to accurately estimate their overall size and mass. We have in these two studies outlined here two extremes. We need more fossils before we can really know which study is most accurate.

Also, it is likely that birds may not be the best models for pterosaur flight as pointed out by Witton and Habib. Birds do things very differently than bats, our only other modern flying vertebrate, and it is most likely that pterosaurs had unexpected adaptations. For example, Habib (2008) is finding evidence for a vaulting launch in the largest pterosaurs.

Check out this video on the Quadrupedal launch in pterosaurs for an interesting viewpoint.

The largest pterosaurs have not been grounded quite yet.

 

References:

Habib, M.B., 2008. Comparative evidence for quadrupedal launch in pterosaurs. Zitteliana, B28: 159-166.

Henderson, D.M., 2010. Pterosaur body mass estimates from three-dimensional mathematical slicing. Journal of Vertebrate Paleontology, 30(3): 768-785.

Witton, M.P. and Habib, M.B., 2010. On the size and flight diversity of giant pterosaurs, the use of birds as pterosaur analogues and comments on pterosaur flightlessness. PloS One, 5(11): 1-18.

 

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