Pterosaurs: Natural History, Evolution, Anatomy

Pterosaurs, flying reptiles from the Mesozoic, have always taken a back seat to dinosaurs in terms of popular books. I own three books on pterosaurs:“The Illustrated Encyclopedia of Pterosaurs” by Peter Wellnhofer from 1991.“The Pterosaurs: From Deep Time” by David Unwin from 2005."Pterosaurs" by Mark Witton from 2013.These are all excellent books. The last is the subject of today's review. You should not confuse the Witton book "Pterosaurs" with a book from 2012 "Pterosaurs: Flying Contemporaries of the Dinosaurs," of which Witton is one of three coauthors.By the way, the first popular book on pterosaurs "Dragons of the Air" (1901) by H.E. Seeley is available as a free e-book at [...]Witton is at the School of Earth and Environmental Sciences at the University of Portsmith. He is a freelance artist as well as a paleontologist and has a blog at [...] .I will start with a little background on pterosaurs, which will make further discussions more understandable. Pterosaurs are the first vertebrates that learned powered flight. Compared to most vertebrates, pterosaurs tend to have extremely large heads and extremely small legs relative to their torsos. Many pterosaurs had a large ridge of bone above their dorsal vertebrae called the notarium, to which the scapula sometimes articulated. Bird wings are made of feathers attached to their (relatively short arms). Bat wings are made from skin stretched between the body and between five elongated fingers. Pterosaur wings were made from skin stretched from the body to an enormously elongated fourth finger, which is unique among vertebrates. There are enough fossils preserving the soft tissue of pterosaur wings, which is typically a few millimeters thick, that we can tell the wings contained, starting from the ventral side, a layer of blood vessels, a layer of muscle, and a layer of semi-rigid fibers. The wings and body of pterosaurs probably had some kind of fur or protofeathers, it is hard to tell which. All pterosaurs had a unique splint-like bone at the wrist called the pteroid, probably used to change the shape of the leading edge of the wing.Despite having a very different wing structure, pterosaurs are convergent with birds on may features. They had bones with very thin walls (presumably for lightness). They had very rigidified ribcages, and there is evidence in the bones for air sacs. Presumably these features could have allowed for an efficient one-way respiration system as in birds. Their brains tended to be large and globular, like a bird’s, and not elongated like a typical reptile’s. All these point to a life as agile fliers requiring large amounts of energy. (Forget the antiquated idea of pterosaurs as gliders needing to jump off high cliffs to fly.)Classically pterosaurs are divided into two types: rhamphorhynchoids (named for Rhamphorhynchus) and pterodactyloids (named for Pterodactylus). Rhamphorhynchoids lived from the Late Triassic until the Early Cretaceous. They generally were small and had large toothed heads on a short neck. They also had long tails with a rhomboid shaped vane at the end. Pterodactyloids lived from the Middle Jurassic until the Late Cretaceous. The had large heads on long necks, but no tails. Many of them were toothless.The fact that pterosaur bones are hollow means that most fossils end up looking like “roadkill,” and the fine anatomical details, such as the shape of the joints, is usually erased.Aspects of pterosaurs that were mysteries for 100 years are not so much of a mystery since about a decade ago. There are enough well-preserved specimens (e.g. from China) that we know where the wing membrane attached to the body. We have enough pterosaur trackways that we have a good idea of how they handled themselves on land: as quadrupeds walking with their legs underneath, walking on wrist pads and the sole of the foot. There are now several known pterosaur eggs, and we know pterosaur babies probably could fly as soon as they hatched. What remains a mystery is which branch of archosaurs the pterosaurs arose from. Also we do not know a specific animal that could be the "protopterosaur" ancestor, that could perhaps climb trees and glide in the style of a flying squirrel, but not fly.Witton's "Pterosaurs" has 26 chapters, the first 8 deal with general findings on pterosaurs, their anatomy, how they flew, how they got along on the ground, how they reproduced, etc. This is very similar to what you find in Unwin's book. One interesting perspective from Witton is about the idea of "weight reduction." The classical idea is that pterosaurs acquired hollow bones and air sacs to make them lighter and more airworthy. Witton reverses this and says the idea is to take animals of a constant weight and make them larger (e.g. more surface area for flight). I'm not sure one can really distinguish the two in practice, but it is thought-provoking. Another idea presented by Witton is that the masses of pterosaurs are underestimated by most workers in the field, such that the mass per wing area is much smaller than that of living birds. If we allow for larger masses in pterosaurs, we can allow for more powerful muscles, which are needed for flight.The real uniqueness of Witton's "Pterosaurs," compared to Unwin's book, is in the15 chapters on individual pterosaur subgroups. (There is a small irony here because the taxonomy is based on Unwin's system.) Each group is presented in detail: a discussion of each genus, unique features, the probable lifestyle, etc. Literature references are included. These chapters can be a little tough to get through in spots, since they are something like a professional review article, but that makes this book useful for professionals as well as interested amateurs like us. The first thing you learn is that pterosaur group names are pretty hard to remember (Anurognathidae, Wukongopteridae, Ctenochasmotoidae, etc.) But the important thing is that if you look within each group there is a tremendous diversity: longer vs. shorter heads, teeth vs. no teeth, crests vs. crests, larger vs. smaller legs and feet, long wings vs. short, claws on the hand vs. no claws, etc. Thus, pterosaurs were probably as diverse in anatomy and lifestyle as birds are now. Witton points out that the classical division into rhamphorhynchoids and pterodactyloids might not be useful in the sense that while pterodactyloids are probably a monophyletic group, the rhamphorhynchoids are probably a collection of primitive types, that might not be closely related to each other. Also, while we are pretty sure more groups of pterosaur are not likely to be identified, we know hardly anything about some groups like the Lonchodectidae because their remains are just so fragmentary.Pterosaurs can have some really bizarre anatomy. For my money, the most bizarre snout belongs to Pterodaustro (from South America). Both its mandible and maxilla are upturned. The lower jaw has hundreds of extremely elongated teeth arranged in a comb-like formation. One can only imagine Pterodaustro using this apparatus to filter feed like a flamingo. The most bizarre crest is found in Nyctosaurus (from Kansas). The crest branches into two cylindrical spars, one pointing up and one pointing back. The crest is about three times as long as the skull and about 20% longer than the head, body, and legs combined. You look at this animal and your first thought is "No way that can be real." However, there are two specimens with the crest intact, so there is no doubt.Speaking of crests, my impression from "Pterosaurs" is that the proportion of pterosaurs with crests is higher than anyone suspected before. While the crests of many pterosaurs are bony, or partly bony, some crests consist only of soft tissue. We see more of the latter now because we have more specimens with preserved soft tissue and/or we now know to look for soft tissue in fossils with ultraviolet light. The original Pterodactylus from Solnhofen, for instance, one of the first pterosaurs known, has a soft tissue crest along its entire snout. While a number of authors have suggested crests could have some aerodynamic or thermal function, it is most likely they were for sexual display since closely related species have different crests.Pterosaurs attained a size range that birds never came close to matching. Quetzalcoatlus (from Texas) is usually depicted as the largest known pterosaur in popular books, but Quetzalcoatlus belongs to a family of extremely large pterosaurs, the Azhdarchidae. The largest known is Hazegopteryx. It probably stood as tall as a giraffe, had wingspan of about 11 meters, and had the longest skull (3 meters) of any non-marine tetrapod. It is interesting that there are many large flightless birds, but as far as we know, there are no secondarily-flightless pterosaurs, even among the largest ones.The writing style of "Pterosaurs" is pretty informal, despite the "review article" format, sometimes verging on "cuteness." I don't mean this in a bad way. I was amused by section headings such as "In the Absence of Proper Data, Speculate Wildly" and figure captions such as "Tupandactulus imperator doing his best Clint Eastwood impression on the scrubby hinterland of the Aptian Crato lagoon.""Pterosaurs" has the expected photographs of fossil specimens and some very clear diagrams, plus world maps showing where key pterosaurs fossils are found. The pictures that depict living pterosaurs are of two types: the pterosaur in a standard "takeoff" pose, such that different genera can be compared, and the pterosaur in "real life" situations, flying, fighting, eating, etc. All of the restorations are watercolors done by the author. I enjoyed them and they get the point across, but they struck me as more "artistic" than "scientific", compared to comparable illustrations by, say, John Gurche.This book is well worth reading and is available at a reasonable price.

There once was a time that dragons flew through the air. Not the dragons of myth and legend but real flying reptiles that prospered and diversified during the Age of Dinosaurs. They didn't breathe fire but they were magnificent, marvelous creatures non the less. In Pterosaurs, Author/Paleontologist Mark P Witton has written what is probably one of the most comprehensive treatment of these unique animals to date. Although this well written book is accessible to the lay reader, I think it was meant primarily for the professional or student paleontologist. In depth and up to date (as of 2013), Pterosaurs delves into the anatomy, evolution and behavior of these "Dragons of the Air". Parts of the book are quite technical, the chapters on skeletons and soft tissue are rather daunting but Witton does a good job, giving the reader a kind of "Anatomy 101". Chapters 10 through 25 spotlight the various kinds of pterosaurs and the author pulls no punches when it comes to naming body parts and the scientific names of each species, so be prepared. Over the years since their discovery in the mid 1700s professional interest in pterosaurs has waxed and wained but some new discoveries in the early 20th Century has brought them back into the lime light. Flight is the pterosaurs signature behavior, but how did it come about? They must have had a non flying ancestor that somehow took to the air. Although there are no fossils (so far) of a protopterosaur (HyPtA) the search is on and specialist all over the world are digging in Triassic formations for their elusive remains. Were pterosaurs good or poor flyers? Over the years opinions have fluctuated back and forth but at this point in time the consensus seems to be that they were active, competent flyers. On every aspect of pterosaur study there seems to be a vast difference of opinion among the specialists on; relationships, anatomy, flight ability, fossil analysis, etc, etc, etc.. Each one has his or her own opinion and can make a convincing argument to support their view. Witton is very good about telling all sides of the story as well as his own. Everything we know about pterosaurs comes from fossils of one kind or another. Bones and teeth, all the hard parts, are readily fossilized and have much to tell us. The soft parts; skin, organs, fur, feathers and, in some cases, the remains of the animals last meal can also be fossilized but are very rare. Then there are the so called "trace fossils"; track ways, foraging impressions and the like. When properly analyzed these can reveal many secrets of animal behavior. Witton covers all aspects of fossil interpretation and what they have to say about relationships, flight, reproduction and diet. Interpretation of fossils can lead to speculation on various aspects of the organisms life style but Witton urges caution on that front. For example: is a specimen male or female? Are two slightly different pterosaurs different species or just variation of the form-type? Do head crests indicate male-female difference or growth patterns or different species? This book covers a lot of ground but, still, it doesn't answer all the questions, no book could. In addition to the text, the book has many fine illustrations: maps, graphs, charts, skeletal reconstructions and technical restorations to help you visualize the animals. Additionally, there are some beautiful water-color plates done by the author himself and some exceptional photographs of various fossils under both normal lighting and UV. In spite of some very difficult parts this was a good read and I highly recommend Pterosaurs to anyone with a strong background in science reading. I had no technical or formatting problems with this Kindle edition.LastRanger

The readability of this beautifully illustrated work by Mark P Witton, whose 'flippant prose has been turned into something that reads like science' (his words, not mine) by a lady called Sheila Dean, is first-rate. Mr Witton certainly has a great enthusiasm for his subject which is infectious and I found this book easy to read and absorb. He does all his own illustrations which are not only superb, but also inspiringly helpful.Apparently, our knowledge of pterosaurs has developed at a rocketing rate over the past 25 years as more and more fossil remains of them have been discovered. We now know beyond all reasonable doubt that pterosaurs were covered in something after the fashion of fine hair and that they were very probably hot-blooded. This book also answers a question that has always puzzled me: why are pterosaur wing membranes attached to just the one elongated finger - the one corresponding to our little finger, in fact - and not to several fingers as in bats? The answer is because, when pterosaurs were on the ground, they moved around on all fours and needed the other fingers free to form front feet for walking on.The book contains several excellent illustrations showing clearly how they did this. Several fossilised pterosaur tracks revealing how they walked on all fours, have been discovered in various places. It used to be thought that pterosaurs would have been very clumsy when grounded, but we now know that this was not the case. Unlike pterosaurs, bats cannot walk on all fours simply because most of the fingers of their front feet are used up for supporting the wing membranes. (There is a species of bat native to New Zealand which manages to move around on the ground fairly well after a fashion, but nothing like a trotting pterosaur)Although pterosaurs were not dinosaurs, Mr Witton brings forward evidence to support the belief that they were rather more closely related to dinosaurs than previously thought. It's not yet clear whether or not the insulating down-like covering on pterosaurs was more akin to feathers or hair. We do know that some dinosaurs were covered in downy feathers and that many of them also were probably hot blooded like birds which are descended from them.The book contains chapters on every known pterosaur family beginning with the earliest known pterosaurs which originated in the late Triassic. Pterosaurs continued to develop and branch out throughout the Jurassic period, reaching their zenith by the mid-Cretaceous, after which they gradually declined becoming extinct, along with the dinosaurs, in the great cataclysm at the end of the Cretaceous . Some of the very largest pterosaurs were also the most recent from the late Cretaceous and they were the largest flying animals ever known. One later pterosaur, known as Hatzegopteryx thambema, when it was walking around on all fours with its wings folded up its sides, was nearly as tall as a giraffe and had the largest wingspan of any known pterosaur, bird or bat.This readily accessible work is well supplied with helpful map, diagrams and illustrations and you can actually see pterosaurs walking around on all fours as well as flying all over the place. Mr Witton occasionally indulges us with subtle touches of helpful humour such as the caption to the picture on page 245 depicting two walking and several flying Romanian Hatzegopteryx thambema pterosaurs above the caption: 'Realising that the next chapter is about pterosaur extinction, a flock of Maastrichtian Romanian Hatzegopteryx thambena tries to fly back to an earlier part of the book to avoid the chop.' This is a great work, which really makes you feel that you are living with pterosaurs and I love it. Buy and enjoy.

Everything you ever wanted to know about pterosaurs; and then some! Written by a professional, it is both highly informative about pterosaurs and the latest finds/research as well as extremely engaging (and at times witty). Much more accessible than Unwin's tome and written for the (informed) lay reader, there is however a comprehensive glossary of source material (including papers written by the author) for those who wish to delve beyond the confines of the text and investigate the arguments and counter-arguments for the differing opinions about this most bizzare of beasts. The descriptions of the various clades of pterosaurs (I am finally getting to grips with cladistics) was well thought out and extremely useful in getting a handle on the evolutionary success of these creatures. The illustrations (by Witton himself) are first-rate and have a 'feel' about them which is akin to Ennion's and Warren's watercolour bird paintings. My only grouse is that whoever proof-read this book should be shot; 'textual errors' seemed to me to be numerous and, being pernickity about such things, marred my enjoyment a tad; after all, it is (a) a university publishing house and (b) it costs £25!. However this was not enough to warrant downgrading from a five star appraisal. Altogether a model for how 'natural history' books should be written for the lay reader with little or no detailed knowledge of the field.

Pterosaurs are perhaps the most interesting, bizarre, extraordinary and extreme of any extinct animals, and have been the subject of some of the finest books, combining popular science with academic rigour, on any palaeontological subject. Peter Wellnhoffers "The Illustrated Encyclopedia of Pterosaurs" (1991) is regarded by some - including myself - as the best of all such books, and David Unwin's "The Pterosaurs: From Deep Time" (2005) a worthy successor. When Mark Witton set out to write a book on pterosaurs, it must have been a daunting prospect to match the quality of older works.He has succeeded admirably. It may seem unnecessary to publish a new volume on pterosaurs only a few years after Unwin's but, as Witton makes clear, the volume of new finds and the light they cast on existing material makes it a timely addition to the literature. Of particular note is the recent discovery of pterosaur eggs which have had a considerable impact on our understanding of pterosaur behaviour and growth.The first few chapters cover general areas such as the history of pterosaur research, a overview of their anatomy and what can be deduced of their behaviour and flying abilities. They introduce a relatively high level of technical detail, but general readers should not be put off by this as it gives the information necessary to understand some of the detail in subsequent chapter.The chapter on pterosaur diversity forms a link to chapters on particular clades which form most of the book. Each of these chapters describes the taxonomic relationships of the clade and how it has been interpreted by different authors. The fossils are described and in many cases illustrated with both drawings and photographs, and from this what is understood of their anatomy. Their possible forms of locomotion on the ground, in the air and in some cases in water are explored, as are inferences on their behaviour.The concluding chapter gives an overview of the rise and fall of pterosaurs over geological time, and their decline towards extinction at the end of the Cretaceous period. Several issues are raised, such as the patchiness of the fossil record and if apparent declines in diversity are real, or are the result of collection bias and the low probability that the thin-walled bones of such animals become fossils.I thoroughly enjoyed this book. Witton's style is rather informal, but his coverage of the subject is academically rigorous, and his excellent illustrations convey both his knowledge of and passion for his subject. It tells a great story of the history of extraordinary animals, and should appeal to anyone interested in science, let alone palaeontology. It is worth its cover prices for the illustrations alone, many of which are the work of the author and presented with a quirky sense of humour.My only criticism is minor, and perhaps reflects my pedantry: something is unique or it is not unique. It can't be "very unique". Sorry Mark - and I hope the calcaneal spur heals now that you've learned the folly of persistently wearing high-heeled shoes!

This is a very well written and extremely thorough exposition of the current knowledge on pterosaur history. A reader who has a reasonable knowledge of skeletal anatomy will find the text easier to follow. To be fair the author has set out to explain a range of terms but it is a complex subject and inevitably some slip through. There has been an explosion of knowledge in recent years which adds to the fascination felt for these extinct animals but adds to the frustration felt as we realise how much more there is to know. Mark Whitton is one a of a small group of paelontologists ( I include Robert Bakker in this) who can turn such a text into a 'page turner'. I bought the Kindle version of this. The reader did quite well with the illustrations.

A serious popular science book written by a proper "pterosaurologist" which has opened up their world to me completely. He is fascinated by how they took off from the ground or water, and a large proportion of the illustrations reflect this. It will be very interesting if future discoveries let us know as to how they mated and if they built nests. Not just a book for people interested in "prehistoric monsters" but a readable account of the latest research and findings of this sadly extinct class of creatures.