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Greg Paul’s Dinosaurs: A Field Guide

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Paul (2010): cover of the A & C Black edition.

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Greg Paul is an independent researcher who specialises on dinosaurs; he’s well known for his popular articles and books and his technical papers, but in particular for his hugely influential artwork. Paul’s most recent book – the 2010 Dinosaurs: A Field Guide (aka The Princeton Field Guide to Dinosaurs) – is, simply put, the ultimate Greg Paul book. It’s a large (320 pp.), heavily illustrated catalogue of over 400 reconstructed skeletons, accompanied throughout with life restorations and brief chunks of text that present data on the world’s Mesozoic dinosaur species. The idea that this book might function as a “field guide” is of course fanciful, and indeed it’s stated early on that the book is intended to be “in the style of a field guide”. A lengthy introductory section reviews dinosaur anatomy, biology, evolution, behaviour, and the climate, atmosphere and palaeogeography of the Mesozoic.

Most basic pieces of biographical information about Paul are already well known. Studying informally under the famously iconoclastic Robert Bakker at Johns Hopkins University during the 1970s and 80s, Paul became interested both in the idea that most dinosaurs were metabolically similar to extant mammals and birds, and that dinosaurs (and other fossil archosaurs) were being portrayed inaccurately by other artists. Under Bakker’s guidance, and inspired by the work of Charles Knight and other artists interested in anatomy, Paul honed a distinctive visual style for both the high-fidelity skeletal reconstructions he has become famous for, and for his reconstructions of dinosaurs in their environments.

One of Greg Paul's most famous scenes: the giant Tendaguru brachiosaur Giraffatitan brancai, with the diplodocoid Dicraeosaurus at left. Image (c) Greg Paul.

It is difficult to overstate the impact and significance of Paul’s work. Like it or not, when most of us think about dinosaurs (or other Mesozoic archosaurs), the images we have in our minds are generally “Greg Paul dinosaurs”. Paul wasn’t the first to depict slim-limbed, fully terrestrial sauropods, galloping ornithischians, or theropods with horizontal bodies and tails, drumstick-like shank muscles, or feathery pelts – Bakker did all of this in his articles from the 1960s and 70s. But the fact that Paul did this consistently, produced both black and white illustrations and colour paintings, and became published across popular mainstream sources, soon made him a dominant force in the world of dinosaur art. While many palaeontologists dislike or disagree with what Paul says about dinosaurs and their biology and evolution, I think that his role in the dinosaur renaissance, and especially in the way dinosaurs are portrayed in art and the media, should always be credited (Naish 2009).

Greg Paul's skeletal reconstructions of the iguanodontians Dollodon bampingi (top) and Mantellisaurus atherfieldensis (below). The status of the former is controversial. Images (c) Greg Paul, used with permission.

Furthermore, Paul’s massive influence mostly comes from the fact that his reconstructions have always been based on an underlying, apparently empirical effort to depict anatomy. In an ideal world, all attempts to reconstruct fossil animals would proceed this way; alas, most illustrators of prehistoric life have done their work by looking at mounted skeletons, guessing the limits of the surrounding soft tissue, and producing the final product with little or no recourse to the anatomy of extant animals. Historically, even those who knew anatomy well – Charles Knight is a classic example – thought it ok to imagine dinosaurs with massive, flabby bodies and (paradoxically) small, lizard-like muscles, despite substantial skeletal evidence to the contrary. In articles, papers and books, Paul argued that one should strive to produce multi-view skeletal reconstructions of fossil archosaurs, and that a good understanding of the overlying musculature should result in a reconstructed form that – bar integument – is essentially that of the living animal (Paul 1987, 1988, 1991). His 1987 ‘rigorous how-to guide’ on the reconstruction of dinosaurs and other Mesozoic archosaurs (Paul 1987) remains a classic that has not really been bettered, even if it does now require substantial update.

The Mongolian deinonychosaurs Velociraptor (l) and Saurornithoides (r) squabble over a Protoceratops carcass. Image (c) Greg Paul.

On the subject of integument, Paul has always been careful to restore his archosaurs with the sort of skin known from certain rare fossils – not with the imaginary wrinkled, elephant-like skin so often given to big dinosaurs by naïve artists – or, in the case of smaller or especially bird-like taxa, with feathery or furry plumes, crests or coats. I’m not alone in recalling a time when certain palaeontologists decried the reconstructing of small dinosaurs as feathery or furry as wholly unscientific and as evidence of the obviously inferior intellect and experience of Paul and his artist colleagues, but look where we are now.

Paulian dinosaurs, but not by Greg Paul. This scene - depicting Therizinosaurus, Tarbosaurus and some remarkably stupid avimimid oviraptorosaurs - is by Luis Rey.

In view of all of this, a distinctive ‘Paulian’ style is present throughout the dinosaur art world today, with many artists producing animals clearly inspired in form, pose and posture by – or even direct copies of – Paul’s dinosaurs. The Jurassic Park dinosaurs are Paulian (though, shame about those unfeathered dromaeosaurs and the burly, tree-trunk-like limbs on the brachiosaur): in fact, we even see a Greg Paul skeletal reconstruction in the movie. In view of this movement, artists who produced non-Paulian dinosaurs as late as the 1980s or 90s seemed anachronistic even at the time.

As Paul explains, it has long been an aim to reconstruct, and publish together, the skeletons of “almost all dinosaur species for which sufficient information is available” (Paul 2010, p. 6). A previous effort to produce a compilation of Paulian dinosaurs – the Japanese volume The Complete Illustrated Guide to Dinosaur Skeletons (Paul 1996) – is far less comprehensive, and is also hard to obtain. This new volume is a guide to (nearly) all valid, non-avialan Mesozoic dinosaur species published at the time of going to press. Some species aren’t illustrated because Paul decided that published or illustrated information was insufficient to allow a reconstruction, but all are provided with a brief description. This consists of data on the taxon’s size, age and distribution, but it also includes an ‘Anatomical characteristics’ section.

Ceratosaurus pages from Paul (2010), from Princeton University Press site.

Dinosaurs: A Field Guide really is the sumptuous visual treat that dinosaur fans, and fans of Paul’s artwork and reconstructions, have long wished for. Numerous dinosaurs never before reconstructed by Paul, nor (in cases) by anyone, are present, including the theropods Juravenator, Sinocalliopteryx, Mei long, Jinfengopteryx, a scansoriopterygid (Paul calls it Scansoriopteryx, whereas the name Epidendrosaurus is probably more appropriate), the sauropodomorphs Jingshanosaurus and Gongxianosaurus, the ankylosaurs Saichania and Pinacosaurus, Pachycephalosaurus, and Olorotitan and numerous other hadrosaurs. Surprises come in the form of the apparently ridiculous Atlasaurus, Beipiaosaurus (but see below), the absurdly shaped Gastonia and the impressively long neural spines of Hypacrosaurus altispinus. Paul describes in the Preface how the recent explosion of new dinosaur discoveries – concerning new feathered theropods, new data on dinosaur pigmentation, skin texture, and bizarre new groups like therizinosaurs – make the modern world of dinosaur research radically different from the one he first got to know.

Three negative points

One of the stegosaur pages from Paul (2010), from NHBS site.

Three main points stand out as areas that could definitely have been improved upon. The first concerns the descriptive text, the second the volume’s format, and the third the taxonomy and classification that Paul uses throughout. At this point it has to be noted that this book will primarily be used by artists; it will not be used by, nor is it intended for, technical scientists, the majority of which seem to have little interest in, or knowledge of, inferred dinosaur life appearance.

Negative point 1: descriptive text

On that note, the ‘Anatomical characteristics’ section included in the descriptive text for each species is frequently all but useless, failing to include material that seems appropriate. I think this is because Paul’s general aim was to describe the overall form of the animal as if it were alive, and not to refer to autapomorphies or other distinctive bony attributes. The tendency to describe species as “standard” for their group, or as “uniform” or “fairly uniform” is frustrating, but refers I suppose to the fact that the respective animal is inferred to be typical for its group in general shape. The reference to contemporaneous species as “enemies” is slightly irksome. Should “friends” have been listed as well?

The pages of field guides.

Negative point 2: format

On the second negative point, the book’s format is also frustrating. ‘Field guides’ do not have illustrations of animals scattered throughout: rather, similar species are illustrated together such that the reader can best appreciate their similarities and differences. I really wish that this format had been used in Dinosaurs: A Field Guide – it would have made it so much earlier to compare related animals. To give one example: apatosaurine sauropod skeletons are spread across three pages, making it hard to appreciate how Apatosaurus ajax compares in limb and body proportions to the three species that Paul considers similar enough to be grouped together as ‘Brontosaurus morph’ apatosaurines.

It is also unfortunate that specimen numbers and scale bars are not included alongside the reconstructions. This would have increased the volume’s value enormously and would make it look more authoritative. It’s not as if there wasn’t the room for the inclusion of such data: there are enormous white spaces alongside every single reconstruction. Paul does say early in the book that the specimen numbers of all reconstructed individuals are provided in an online appendix, archived at http://press.princeton.edu/titles/9287.html. A link available through that site does include specimen numbers, but they’re listed in connection with size estimates – it isn’t immediately clear that they refer to the same specimens used in the reconstructions, but I suppose they must.

Negative point 3: taxonomy, phylogeny, nomenclature

How many 'genera' do you see, one or three? It doesn't matter, so long as we know what we mean. Most workers would interpret these three skulls as (clockwise from top left) representing Centrosaurus, Styracosaurus and Pachyrhinosaurus. Images from wikipedia: see below.

On the third negative point, one of the first rules about this book is that Paul’s taxonomy should be ignored. We all know that Greg has his own views on which taxa should be congeneric, but the use of names across the book is misleading and totally confusing, especially for non-specialists. Paul has argued before (e.g., Paul 1988) that dinosaur genera are oversplit and that tyrannosaurid and ornithomimid species, various of the centrosaurine horned dinosaurs, some of the crested lambeosaurine duckbills and so on should really be placed in the same genera, in part because (say) Styracosaurus and Pachyrhinosaurus are (in Paul’s view) more similar to one another than are species included in such extant genera as Varanus. [In composite image above, Centrosaurus by Sainterx, Styracosaurus by Claire Houck, Pachyrhinosaurus by Sebastian Bergmann.] Authors are of course free to reclassify species based on their own understanding or interpretation of phylogenetic relationships (this is itself an unfortunate consequence of the fact that Linnaean binomials frame a specific hypothesis for a taxon’s affinities; they are not just labels). But authors should only do this when they can justify or explain their reclassifications. Paul doesn’t do this, and in fact his reclassifications seem mostly based on whimsy.

But a little of the morphological variation present within Varanus. Top to bottom: Komodo dragon (V. komodoensis), Savannah monitor (V. exanthematicus), Green tree monitor (V. prasinus).

In any case, it is both naïve and futile to imagine that the entities we term genera should be somehow consistent across different animal clades. It doesn’t make any difference as goes our understanding of diversity or phylogeny whether the name Centrosaurus is understood to be unique to the species apertus, or to apply to all species within the clade typically called Centrosaurinae, or whether Centrosaurus encompasses the same amount of morphological disparity as Varanus, Loxodonta or Cricetus; what matters is that researchers within a given subject area use a consistent nomenclature. Many people – and remember that this is a popular volume, not written just for dinosaur nerds and technical specialists – just won’t get it should they see, for example, the Argentinean Giganotosaurus referred to as a species of the otherwise African Carcharodontosaurus. All in all, the taxonomy that Paul opts to use in his volume represents a real failure of communication. Readers will be perplexed, not enlightened. [In adjacent composite, Komodo dragon photographed at ZSL London Zoo, Savannah monitor image by Shizhao, tree monitors by El Cattivo86.]

On a related note, the way in which Paul classifies the species is frustrating, not necessarily because he is idiosyncratic, but rather because the placements he favours are not explained or justified. To take just one example… Sapeornis chaoyangensis – a long-armed, short-skulled, short-tailed theropod with a pygostyle and reversed hallux – is generally regarded as part of Avialae, close in phylogenetic position to the root of Pygostylia (Zhou & Zhang 2002). Yet Paul regards it as an oviraptorosaur – a placement that many of us have considered informally but one which has yet to be supported by any character analysis. The idea that the long-winged, presumably volant Sapeornis might be an oviraptorosaur is, needless to say, an exciting speculation in view of Paul’s idea about the repeated evolution of flightlessness in Mesozoic maniraptorans (Paul 1988, 2002), but that’s all it is – a speculation. The classification of Epidexipteryx hui within Oviraptorosauria also requires explanation, and why is Epidexipteryx regarded as an oviraptorosaur while the extremely similar Epidendrosaurus is not?

In a few cases, Paul uses new names for certain clusters of species. I can understand that one might need to lump animals together into paraphyletic grades for the purposes of a book like this, but I think it’s misleading to refer to (say) non-lithostrotian titanosaurs as ‘baso-titanosaurs’ (as Paul does), since this immediately creates the impression that such a name is in widespread use (it isn’t) and will be understood by others (it won’t). Minmi and Liaoningosaurus are grouped together as ‘minmids’ and what exactly are ‘paxceratopsians’? So far as I can tell, the latter name is wholly novel (Paul uses it for psittacosaurs and neoceratopsians).

One of my favourite Greg Paul pieces: pair-bonded, nesting azhdarchids with altricial chicks fend off a tyrannosaurid. Image (c) Greg Paul. Art like this is controversial specifically because it is bold and daring. And, no, that doesn't mean that I support the behavioural hypotheses depicted in this painting.

In a work of this size, particularly one containing both novel skeletal reconstructions and a huge amount of controversial re-naming and re-classifying, it’s inevitable that numerous small matters of contention will arise. Some researchers say that the very raison d’etre of this work – Paul’s body of high-fidelity skeletal reconstructions – is problematic, with the underlying reconstructive process being subjective, prone to bias and misinterpretation, and far more artistic than Paul makes clear (Mallison 2010, Norman 2011). Producing skeletal reconstructions of this sort involves extrapolation, interpretation and a degree of guesswork, so perhaps it would be helpful – and this is not a specific criticism of Paul, but one that could be directed at all technical skeletal reconstructions – if the reconstructions were framed as hypotheses where some (SOME, not all) of the details are open to alternative interpretations. Indeed, some of the things that look intuitively reasonable in reconstructions – Paul’s quadrupedally bounding plateosaurian sauropodomorphs are a good example – are unlikely to be correct, in this particular case because, among other things (e.g., Mallison 2010), plateosaurs could not pronate the manus (Bonnan & Senter 2007) and were thus likely incapable of quadrupedal walking or running.

Life reconstruction of Guanlong wucaii, by Renato Santos (from wikipedia).

On more trivial matters, I especially disliked seeing the tyrannosauroid Guanlong included among the allosauroids as a second species of Monolophosaurus (note that Monolophosaurus itself is no longer regarded as an allosauroid by other workers: Benson 2010, Brusatte et al. 2010). This idea only has its origin in a conference abstract and its associated presentation (Carr 2006) and the full argument has yet to be presented in print. Whether it withstands scrutiny or not (I agree with Brusatte et al. (2010) that it seems unlikely to be correct), Paul shouldn’t have reclassified Guanlong on the basis of a conference presentation. Neovenator, an uncontroversial allosauroid allied with carcharodontosaurids, is said by Paul to be the centre of a disagreement over whether it’s a tyrannosauroid or allosauroid. Unless I’ve missed something, this is incorrect.

Therizinosaur Beipiaosaurus, with 'dorsal fin' visible above its dorsal vertebrae.

What’s with the crazy ‘dorsal fin made of fuzz’ depicted on the therizinosaur Beipiaosaurus? Paul illustrates another, later therizinosaur – Nothronychus – with a subtriangular ridge in the middle of its back (that is, with the peak of the ridge being mid-way along the length of the torso), but here the ridge is formed by tall neural spines. My hypothesis is that Paul is hinting at the possibility that therizinosaurs found mid-dorsal fins highly fashionable, and swapped soft-tissue ones for bony ones at some point during their evolution (elsewhere in the book, Beipiaosaurus gets referred to as “a refugee from a Warner Brothers’s cartoon” (p. 12)). But is there any evidence for a ‘dorsal fin’ in Beipiaosaurus? An excellent referred specimen preserves the subtriangular patch of integument that Paul has restored as a ‘dorsal fin’ (Xu et al. 2009), but, like other integument-bearing patches preserved adjacent to the specimen, I don’t think you can confidently infer that it represents a soft-tissue structure in life position. The Liaoning Province fossils are mostly flattened. Like most fossils with soft tissues attached, their outlines are not sharp and life-like, but messy and the result of decomposition and compression. Taphonomic experiments have shown that, when the bodies of modern birds are crushed flat, large feathery crests not present in life typically result (Foth 2011).

Reconstructed skull of Nemegtosaurus (though - controversially - given 'cheeks'), by palaeozoologist (NOT by Paul).

Paul puts the Nemegtosaurus skull on the Opisthocoelicaudia body [adjacent skull illustration by palaeozoologist]. This is objectionable if you follow phylogenies where the two are recovered as but distantly related (e.g., Curry Rogers 2005), and it isn’t supported by any overlapping material (see discussion in Wilson 2005). For now, it’s an interesting idea, but not a ridiculous one, especially in view of the fact that – the more we learn about sauropod skulls – the more samey they appear. Also on sauropods, Paul’s idea that the raised tails present in some mamenchisaurid specimens might represent the actual life condition has so far proved unpopular (I know: I brought it to attention at a recent meeting devoted to sauropods). I’ll leave this idea for those with more experience of sauropods and their tails.

The panel-mounted chasmosaurine NMC 8538 as we're used to seeing it. Skull comes from a different specimen and the ribs are scrunched up on right side. Photo courtesy of ReBecca Hunt-Foster.

Styracosaurus albertensis (Centrosaurus albertensis of Paul’s usage) is illustrated with an enormously long, tapering nasal horn, despite the fact that Ryan et al. (2007) showed the actual horn to be about half as long as the one reconstructed on mounted specimens. Also on ceratopsids, we now know that the wonderfully complete ‘Anchiceratops ornatus’ skeleton NMC 8538 (shown here), reconstructed by Paul, is a composite (the skull is a cast from another specimen). Furthermore, it turns out that it was only ever identified as Anchiceratops by default, not because it can be convincingly referred to this taxon (Mallon & Holmes 2010). On the subject of ceratopsians, Cerasinops is inadvertently featured twice in the book, and Paul accepts the proposal that Torosaurus is a growth stage of Triceratops, not a separate taxon. On ornithopods, we now know that the cranial crest of Tsintaosaurus spinorhinus is not just a sub-vertical spike as classically depicted, but a more complex structure. I think that some of the dryosaurids in the book are incorrectly labelled.

Another of my favourite Greg Paul paintings. Giraffatitan and Ceratosaurus ingens contemplate one another; pterosaurs and a mammal are in the foreground. The full version includes several diplodocids at far right. Image (c) Greg Paul.

It’s a matter of taste whether you like or dislike Paul’s artwork. The flat horizons, low viewer angle, and tendency of animals to be depicted in tidy profile are features disliked by some. And a minor artistic and scientific movement away from ‘shrink-wrapped’, Paul-style dinosaurs (that is, those where the edges of many of the skull bones, and the distinct margins of the bony skull openings, are far more distinct than they are in any living animals) is currently underway. Anyway, those who enjoy Paul’s colour pieces will be happy to see several new ones included here. Paul also includes modified, ‘colourised’ versions of pieces that were either originally produced in black and white, or originally showed the animals standing alone, without any obvious background. These haven’t worked at all in my opinion (e.g., Lesothosaurus diagnosticus on p. 216, Euoplocephalus tutus on p. 235). The many small life reconstructions of animal’s heads suffer from their fuzzy outlines – a real contrast to the typically sharp lines of Paul’s artwork.

Some of the spelling is sloppy. ‘Ornithsichians’ are mentioned on p. 273 and Paul’s own taxon Dollodon bampingi is consistently referred to as Dollodon bambingi (pp. 289-290). Then there’s Crylophosaurus (p. 11) (= Cryolophosaurus), Pacycephalosaurus (p. 22) (= Pachycephalosaurus), Archiornis (p. 52) (= Anchiornis), Pycnoneosaurus (p. 79) (= Pycnonemosaurus), Aerosteons (p. 99) (= Aerosteon), Ansermimus (p. 113) (= Anserimimus) and so on.

What is the purpose of this book? People will enjoy looking at it, for sure, but doesn’t Paul produce those high-fidelity skeletal reconstructions so that other scientists and artists have access to excellent, useable data on the animals that Paul reconstructs? Well, no, apparently not, for the great irony is that a major ruckus erupted in the dinosaur art world at about the same time as this book appeared in print.

The 'no GSP' logo you can find online. I won't say who produced it.

Apparently inspired by the fact that he was losing paying work to competitors, Greg Paul spent considerable time and effort during 2011 demanding that other artists stop using his work as reference points for their own art, that people compensate him adequately should they use or pass his reconstructions on to others, and that those who produce skeletal reconstructions of their own should ensure that the poses they choose are visually distinct from the Greg Paul standard. Paul’s proposals understandably caused great animosity from many quarters: an enormous amount of discussion is archived online on this issue at blogs and the dinosaur mailing list and I don’t wish to cover it here. Suffice to say that, while Paul should get appropriate credit for his work and art, he cannot and will not stop people from using his published work as an available resource.

Princeton University Press cover.

Any lengthy piece of work by Greg Paul is likely to attract a degree of criticism, either because of his taxonomic and phylogenetic proposals, because of certain controversial or uncertain details of his reconstructions or art, or because of his outspoken views on dinosaur physiology or behaviour. But, then, these areas are part of the appeal. People like reading what Paul writes because he is well known for being controversial; for promoting new and sometimes daring and weird ideas about dinosaur evolution, biology, locomotion and behaviour. This is the person who was arguing for feathered theropods and fuzzy ornithischians before such ideas went mainstream, argued for the evolution of widespread secondary flightlessness across maniraptoran theropods, and worked to emphasise the idea that watching live dinosaurs would be like watching modern animals on the Serengeti – there would be dust in the air, interspecies conflicts, occasional herbivory in predators and occasional carnivory in herbivores. If Dinosaurs: A Field Guide is anything, it is indeed a visual treat, with reconstructions of tens of species representing most of Mesozoic dinosaur diversity as we currently understand it. What’s more, the book is extremely affordable for its size and quality. Bottom-line: most people interested in dinosaurs will value it, despite its problems.

The book comes in two editions. The US version, published by Princeton University Press, features two running tyrannosaurs on the cover and is properly titled The Princeton Field Guide to Dinosaurs. The UK version, published by A & C Black, is black with six life restorations on the cover. The cover image shown at the very top of this article has three ostrich dinosaurs at the top and I’m not sure if this version exists in the real world: the one I have with me here now features Leptoceratops, Euoplocephalus and Shantungosaurus at the top.

Paul, G. S. 2010. Dinosaurs: A Field Guide. A & C Black (London). Hardback, index, refs, pp. 320. ISBN 978-1-4081-3074-2.

For previous Tet Zoo articles relevant to some of the stuff discussed here, see…

Refs – -

Benson, R. B. J. 2010. A description of Megalosaurus bucklandii (Dinosauria: Theropoda) from the Bathonian of the UK and the relationships of Middle Jurassic theropods. Zoological Journal of the Linnean Society 158, 882-935

Bonnan, M. F. & Senter, P. 2007. Were the basal sauropodomorph dinosaurs Plateosaurus and Massospondylus habitual quadrupeds? Special Papers in Palaeontology 77, 139-155.

Brusatte, S. L., Benson, R. B. J., Currie, P.  J. & Zhao, X. 2010. The skull of Monolophosaurus jiangi (Dinosauria: Theropoda) and its implications for early theropod phylogeny and evolution. Zoological Journal of the Linnean Society 158, 573-607.

Carr T. 2006. Is Guanlong a tyrannosauroid or a subadult MonolophosaurusJournal of Vertebrate Paleontology 26, 48A.

Curry Rogers, C. 2005. Titanosauria: a phylogenetic overview. In Curry Rogers, C. & Wilson, J. A. (eds) The Sauropods: Evolution and Paleobiology. University of California Press (Berkeley), pp. 50-103.

Foth, C. (2011). On the identification of feather structures in stem-line representatives of birds: evidence from fossils and actuopalaeontology Paläontologische Zeitschrift DOI: 10.1007/s12542-011-0111-3

Mallison, H. 2010. The digital Plateosaurus II: An assessment of the range of motion of the limbs and vertebral column and of previous reconstructions using a digital skeletal mount. Acta Palaeontologica Polonica 55, 433-458.

Mallon, J. C. & Holmes. R. 2010. Description of a complete and fully articulated chasmosaurine postcranium previously assigned to Anchiceratops (Dinosauria: Ceratopsia). In Ryan, M. J., Chinnery-Allgeier, B. J. & Eberth, D. A. (eds) New Perspectives on Horned Dinosaurs: the Royal Tyrrell Museum Ceratopsian Symposium. Indiana University Press (Bloomington and Indianapolis), pp. 189-202.

Naish, D. 2009. The Great Dinosaur Discoveries. University of California Press (Berkeley and Los Angeles).

Norman, D. B. 2011. Ornithopod dinosaurs. In Batten, D. J. (ed.) English Wealden Fossils. The Palaeontological Association (London), pp. 407-475.

Paul, G. S. 1987. The science and art of restoring the life appearance of dinosaurs and their relatives – a rigorous how-to guide. In Czerkas, S. J. & Olson, E. C. (eds) Dinosaurs Past and Present Vol. II. Natural History Museum of Los Angeles County/University of Washington Press (Seattle and London), pp. 4-49.

- . 1988. Predatory Dinosaurs of the World. Simon & Schuster (New York).

- . 1991. The many myths, some old, some new, of dinosaurology. Modern Geology 16, 69-99.

- . 1996. The Complete Illustrated Guide to Dinosaur Skeletons. Gakken.

- . 2002. Dinosaurs of the Air: the Evolution and Loss of Flight in Dinosaurs and Birds. Baltimore: Johns Hopkins University Press (Baltimore), pp. 536.

- . 2010. Dinosaurs: A Field Guide. A & C Black (London).

Ryan, M. J., Holmes, R. & Russell, A. P. 2007. A revision of the late Campanian centrosaurine ceratopsid genus Styracosaurus from the Western Interior of North America. Journal of Vertebrate Paleontology 27, 944-962.

Wilson, J. A. 2005. Redescription of the Mongolian sauropod Nemegtosaurus mongoliensis Nowinski (Dinosauria: Saurischia) and comments on Late Cretaceous sauropod diversity. Journal of Systematic Palaeontology 3, 283-318.

Xu, X., Zheng, X. & You, H. 2009. A new feather type in a nonavian theropod and the early evolution of feathers. Proceedings of the National Academy of Sciences 106, 832-834.

Zhou, Z. & Zhang, F. 2002. Largest bird from the Early Cretaceous and its implications for the earliest avian ecological diversification. Naturwissenschaften 89, 34-38.

Darren Naish About the Author: Darren Naish is a science writer, technical editor and palaeozoologist (affiliated with the University of Southampton, UK). He mostly works on Cretaceous dinosaurs and pterosaurs but has an avid interest in all things tetrapod. His publications can be downloaded at darrennaish.wordpress.com. He has been blogging at Tetrapod Zoology since 2006. Check out the Tet Zoo podcast at tetzoo.com! Follow on Twitter @TetZoo.

The views expressed are those of the author and are not necessarily those of Scientific American.





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  1. 1. John Conway 1:32 pm 02/21/2012

    I concur with everything you’ve said (in this review). I wish Greg would give up on taxonomic fiddlings and concentrate more on anatomy.

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  2. 2. naishd 1:33 pm 02/21/2012

    Aww, shucks – I thought you meant everything I’ve said, ever.

    Darren

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  3. 3. Halbred 2:29 pm 02/21/2012

    For my money, the book is infuriating to read, but pretty to look at. The taxonomic quibblings would be more tolerable if Paul was more consistent: centrosaurines get the short stick, but chasmosaurines are relatively stable. Ornithomimids were all lumped together, but hadrosaurs retained their generic diversity for the most part. And you’ve mentioned the bizarre cases with Sapeornis, Epidexipteryx, and Guanlong. I’m not sure where he’s getting these ideas (apart from Guanlong’s case).

    I own the book–although I apparently can’t use it for reference purposes–and I do enjoy leafing through it now and then, but its utility is ultimately limited.

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  4. 4. michaels07 3:15 pm 02/21/2012

    I have the book and enjoy looking at the illustrations, since I was a Child i like many others have been fascinated by the Dino World.Since I am a novice even at my age i can`t argue about the books scientific merit.

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  5. 5. Brad McFeeters 3:51 pm 02/21/2012

    Paul also claims “Omeisaurustianfuensis and various “Mamenchisaurus” referred species are too different in their overall body plans to really belong to those genera… but there are no reconstructions of the type species for the reader to compare them to, so why would anyone find this persuasive?

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  6. 6. dinogami 4:10 pm 02/21/2012

    Purely as a matter of personal taste (and not a concern about actual content, such as those that Darren pointed out), I was extremely surprised that the majority of the illustrations in the book were…well, not what one has come to expect from Greg Paul! They appear to have been done in colored pencil, and lack the vivacity and, frankly, solidity of any previous Greg Paul illustration that I have seen. I don’t mind colored pencil as a medium…but for the purposes of creating life-like portraits of the animals, it fell quite flat. Of course, it would have taken Greg an inordinately long time to produce each portrait in his usual painting style, and that’s unreasonable to have expected, but I would have rather had his terrific black-and-white pencil sketches than what are in this book.

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  7. 7. MMartyniuk 4:58 pm 02/21/2012

    “Paul calls it Scansoriopteryx, whereas the name Epidendrosaurus is probably more appropriate”

    Whether or not it seems more appropriate, Epidendrosaurus was an online-only name until well after Czerkas self-published Scansoriopteryx.

    I agree that the Beipiaosaurus is one of the weirdest aspects of this book. In fact despite having pioneered feathered dinosaurs, most of Paul’s maniraptorans look more like “dinosaurs with feathers” as Andrea Cau put it. Aside from the obvious issue of restoring these things as if they were decaying theropodan zombies with frayed patches of integument all over the place, something about the appearance of the feathers themselves, the way wings fold, etc. doesn’t look natural (I suspect some of this is a compromise allowing Paul to “show his work” and not hide the anatomical details under integument).

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  8. 8. Henrique Niza 5:02 pm 02/21/2012

    I mainly agree with your negative point 3. I don’t mind Greg Paul’s taxa lumping because I could actually see myself agreeing with some but without an explanation as to why it looks somewhat… incomplete, for lack of better word. I definitely agree people that aren’t “dino-nerds” will probably scratch their heads with many of the terms and names of the book.

    But anyway, I basically grew-up with Greg Paul artwork and Greg Paul inspired artwork, and I found in this book the perfect opportunity to get something from him.

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  9. 9. Heinrich Mallison 5:18 pm 02/21/2012

    This is such an enormously fair review that I herewith nominate you for the FBPotY* award! It’s not even March, but nobody’s going to be able to beat this :)

    *Fairest Blog Post of the Year

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  10. 10. naishd 5:28 pm 02/21/2012

    Thanks for comments so far, much appreciated. Scansoriopteryx vs Epidendrosaurus (comment 7): the situation with these two names is a little complicated, as Harris (2004) explained. For one thing, the volume containing Scansoriopteryx wasn’t technically “available” (according to the provisions of the ICZN) until Sept 2nd 2002, after the digital publication of the Epidendrosaurus paper (Aug 21st 2002). I suppose your point remains that Epidendrosaurus was, however, digital-only while Scansoriopteryx was out on paper. It’s so dumb though – I mean, I saw Epidendrosaurus printed on paper before the Scansoriopteryx paper was available for purchase.

    Darren

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  11. 11. naishd 5:32 pm 02/21/2012

    Heinrich (comment 9) – whoop, thanks :)

    Darren

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  12. 12. JAHeadden 5:44 pm 02/21/2012

    It doesn’t make any difference as goes our understanding of diversity or phylogeny whether the name Centrosaurus is understood to be unique to the species apertus, or to apply to all species within the clade typically called Centrosaurinae, or whether Centrosaurus encompasses the same amount of morphological disparity as Varanus, Loxodonta or Cricetus; what matters is that researchers within a given subject area use a consistent nomenclature.

    I think the point here is that everyone who changes nomenclature should have explicit reasons for altering previous nomenclature (such as naming new “genera” to contain older species, or conjoining species and thus tossing out previosuly supposed “genera”). The big lesson from Paul is that his reasoning is typological: he eschews now seemingly standard practices of explicit phylogenetic analysis for the sake of gut-based, “feels-right” hunches. This leads to there being no real line between what the “consensus” has to say about the nomenclature, and what Paul alone has to say about it.

    I mentioned much of this here, where I focused on one egregious portion of his non-explicit, gutsy lumping of taxa, and I couldn’t even finish the attempted “nice” review of the larger work, posted in part here. Mickey Mortimer followed my review of “Citipati gracilis” with his own look here, where he then goes into detail in the different major subgroups and what Paul did with them, taxonomically. Pal follows a very iconoclastic path for his “analyses,” one which doesn’t lend itself well to the scientific model of falsification or verifiability, and that is telling. Much of it has to do with the wholly artistic endeavor of renaming things for the sake of how they “feel” (remember, Paul doesn’t use phylogenetic analysis to test phylogenetic hypotheses, he uses his gut). This is the biggest takeaway from the book, and any review that doesn’t come up slammed in the face from the inability to parse the “Why” of his nomenclature will find this a bigger pill than can be swallowed.

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  13. 13. naishd 5:52 pm 02/21/2012

    “and any review that doesn’t come up slammed in the face from the inability to parse the “Why” of his nomenclature will find this a bigger pill than can be swallowed”

    - – so, did I fail? Can’t tell from your wording. Thanks for comment though, Jaime. As I just said to Andy Farke on twitter, I “deliberately didn’t read other reviews to stay untainted by thoughts of others :) ”.

    Darren

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  14. 14. JAHeadden 7:19 pm 02/21/2012

    No, I think you did an admirable job of trying to be positive, given the subject. Note that I also tried … and could only remark on the quality and number of reconstructions offered. Thus, my own review was … subjective. The point I was trying to make had nothing to do with your particular review, but extending the comments about the taxonomy.

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  15. 15. JAHeadden 7:24 pm 02/21/2012

    Ooops — I meant to add:

    It would have been an interesting tangent to note that there isn’t a strict consensus on varanid “generic” taxonomy, and some authors suggest that the current “subgenera” splitting of Varanus should be its “generic” splitting, making “species groups” into “genera.” The major problem with this is merely that it is not conventional, and that this step is simply not scientific.

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  16. 16. naishd 7:25 pm 02/21/2012

    Ok, thanks. Sorry for misunderstanding.

    Darren

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  17. 17. naishd 7:32 pm 02/21/2012

    By the way… Varanus – well, I’ve actually written about this a few times on Tet Zoo (mostly in the comments). Yes, there is a complex history of people naming ‘subgenera’ within Varanus, but it doesn’t seem that we’re going to see an end to the super-inclusive version of Varanus any time soon, especially given that none or few of those traditional ‘subgenera’ have been established to be monophyletic. In any case, as people give up on the idea of hierarchical ranks and move increasingly to the idea that clades can be named wherever they are in the tree, there is a trend for people to be happy with the recognition of, say, an Odatria that represents a clade within Varanus. Losos covers this in his excellent recent book on anoles – and he’s writing, of course, about one of the ‘lumpiest’, most arguably-in-need-of-splitting tetrapod ‘genera’ of them all.

    Darren

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  18. 18. Therizinosaurus 8:00 pm 02/21/2012

    Overall a good review that agrees with mine in most respects, you just seem to value art more than I do.

    I gotta disagree in that I consider Dinosaurs of the Air to be the ultimate Greg Paul book. You say yourself the text of the Field Guide is “frequently all but useless” and the taxonomy “should be ignored.” Which leaves us with a bunch of pretty pictures, while DA actually has exhaustive and interesting text.

    I’m curious if your cover is also like the picture you show in mislabeling every taxon Alwalkeria maleriensis.

    I was all ready to plug my own reviews of Paul’s “field guide”, but I see Jaime did it for me in the comments. One thing I’ve noticed since then based on coding Beipiaosaurus is that it doesn’t have the weird pointed snout Paul gives it. The pointiness is an illusion caused by the palatal shelf on the left premaxilla of STM31-1, while the right premaxilla is exposed in lateral view and shows a more normal blunt snout.

    I see Matt already caught that Scansoriopteryx was published in print before Epidendrosaurus. I agree the ICZN is dumb in this respect, but we have nothing else to follow. Because of it, a few of the dates on my website are wrong, and I’ll have to go through it soon and check for taxa which were technically named a year later than I have them.

    Halbred said “you’ve mentioned the bizarre cases with Sapeornis, Epidexipteryx, and Guanlong. I’m not sure where he’s getting these ideas (apart from Guanlong’s case)”
    The Sapeornis thing is no doubt ultimately based on Czerkas and Ji’s (2002) Omnivoropteryx paper which noted the strong resemblence between omnivoropterygids and caudipterid skulls. Zhang et al. (2008) stated “Epidexipteryx and Epidendrosaurus also show some striking similarities to oviraptorosaurs.” Xu et al. (2011a, 2011b- the SVP abstract and Xiaotingia paper) seemingly agree, and miscode these taxa in several ways to make them seem more similar. For instance, they wrongly code Epidexipteryx and Sapeornis as having oviraptorid-like premaxilla-antorbital fossa contact and a caudipterid-like enlarged first premaxillary tooth for instance, and Scansoriopteryx as having a significantly dorsally angled posterior lacrimal process like oviraptorosaurs. So I wouldn’t be surprised to see this relationship supported explicitly in analyses soon, but if it is, be sure to check coding accuracy.

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  19. 19. naishd 8:21 pm 02/21/2012

    Mickey – good points :) Yes, I obviously like pretty pictures, and I will admit that I was an idiot in thinking that an “ultimate Greg Paul book” would be a compilation of illustrations, not a wordy tome like DA. No, the cover does not have all taxa labelled as Alwakeria, though the coelophysid is wrongly labelled Acrocanthosaurus. Regarding the ICZN and Epidendrosaurus, I’m too tired to check (I’m all ICZNed-out right now) but if you check Article 8 of the Code there is considerable ambiguity over what is classified as ‘published’. I expect someone to beat me down with relevant quotes and cited passages, but it isn’t clear that digital publications don’t count.. plus there’s all that slop about when the Czerkas volume was really “available”.

    Omnivoropteryx and scansoriopterygids: good point on coding accuracy. It’s easy to see superficial similarities in, say, skull shape and jump to conclusions. But people need to remember that the characters that make certain maniraptorans look oviraptorosaur-like or troodontid-like, say, are actually tremendously labile in other dinosaur (and tetrapod) clades.

    PS – It might be helpful to have a linked list of all online reviews of Paul (2010) in one place. Anyone want to do it? I can tweak the html behind the scenes if need be.

    Darren

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  20. 20. Therizinosaurus 11:42 pm 02/21/2012

    Well, since you asked for an ICZN beat down…

    “Article 9. What does not constitute published work.”
    “9.8. text or illustrations distributed by means of electronic signals (e.g. by means of the World Wide Web);”

    The relevent part of Article 8 is

    “8.6. Works produced after 1999 by a method that does not employ printing on paper. For a work produced after 1999 by a method other than printing on paper to be accepted as published within the meaning of the Code, it must contain a statement that copies (in the form in which it is published) have been deposited in at least 5 major publicly accessible libraries which are identified by name in the work itself.”

    And since the electronic form of Zhang et al. (2002) (which I still have a copy of) merely states it was published online, not deposited in five physical libraries, it doesn’t count.

    As for when Czerkas’ volume was out, Olshevsky and Ford both got copies by September 4th (http://dml.cmnh.org/2002Sep/msg00075.html and http://dml.cmnh.org/2002Sep/msg00078.html).

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  21. 21. Andreas Johansson 3:48 am 02/22/2012

    Obedient to the rule that anything criticizing spelling or grammar to has to have a similar error, you’ve missed an ‘s’ in Opisthocoelicaudia.

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  22. 22. naishd 3:50 am 02/22/2012

    Andreas: ha ha, I was expecting someone to say “Glass houses, thrown stones” at some point. Thanks.

    Darren

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  23. 23. Dartian 7:51 am 02/22/2012

    Darren:
    The reference to contemporaneous species as “enemies” is slightly irksome.

    That’s about as silly as Paul’s use of the word “firepower” when describing the dromaeosaurs’ claws in Predatory Dinosaurs of the World.

    it doesn’t seem that we’re going to see an end to the super-inclusive version of Varanus any time soon, especially given that none or few of those traditional ‘subgenera’ have been established to be monophyletic

    Tradition didn’t stop people from taking the viviparous lizard out of Lacerta and placing it in the monotypic Zootoca. Nor did tradition stop people from taking the natterjack toad out of Bufo and placing it in the monotypic Epidalea. Why should Varanus be treated any differently? If herpetologists think it’s too inclusive, they should just split it already and be done with it.

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  24. 24. David Marjanović 1:02 pm 02/22/2012

    It is also unfortunate that [...] scale bars are not included alongside the reconstructions.

    …Oh fuck. That makes it useless for me. To update and publish my MSc-equivalent thesis on the evolution of body size in Mesozoic dinosaurs, I’ll someday need as many measurable skeletal reconstructions as possible – I may well have ended up buying this book, but if there are no scale bars in it, I can forget about it.

    But authors should only do this when they can justify or explain their reclassifications. Paul doesn’t do this, and in fact his reclassifications seem mostly based on whimsy.

    Unfortunately, that’s perfectly fine with the ICZN.

    It’s so dumb though – I mean, I saw Epidendrosaurus printed on paper before the Scansoriopteryx paper was available for purchase.

    Apparently it’s difficult to establish when the print issue with Epidendrosaurus in it was actually published. Is “September 30th” just a default derived from Art. 21.3.1? And has anybody seen both specimens?

    >>
    21.3. Date incompletely specified. If the day of publication is not specified in a work, the earliest day on which the work is demonstrated to be in existence as a published work is to be adopted as the date of publication, but in the absence of such evidence the date to be adopted is

    21.3.1. the last day of the month, when month and year, but not day, are specified or demonstrated, or

    21.3.2. the last day of the year when only the year is specified or demonstrated.
    <<

    So I wouldn’t be surprised to see this relationship supported explicitly in analyses soon, but if it is, be sure to check coding accuracy.

    Heh.

    Nor did tradition stop people from taking the natterjack toad out of Bufo and placing it in the monotypic Epidalea.

    But that was done as part of a great big phylogenetic revision. All the genera that replace Bufo in the traditional sense came out as monophyletic in the analysis by Frost et al. (2006) who did the taxonomic revision. Such an analysis still hasn’t been done for Varanus.

    Bufonid genera, with number of included species for each, on the AMNH site curated by Frost. Yes, Epidalea has 1 species, but Pseudepidalea has 16, Amietophrynus has 39, and Rhinella (R. marina is the former Bufo marinus) has no less than 86…

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  25. 25. Heteromeles 2:00 pm 02/22/2012

    I may be off base here, but it certainly looks (to an outsider) that Paul is arguing from the stance of old-school evolution, whereas the criticisms are coming from people who were first educated in cladistics.

    This isn’t a criticism of cladistics, since that’s where I’m coming from too. It’s just that evolutionary arguments used to be weighted more by appeals to the eminence, experience, and reputation of the systematists involved, rather than by objective tests of hypotheses against data sets.

    Does Paul have a cladistics background that I’m missing?

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  26. 26. Henrique Niza 4:08 pm 02/22/2012

    “You say yourself the text of the Field Guide is “frequently all but useless”… [w]hich leaves us with a bunch of pretty pictures, while DA actually has exhaustive and interesting text.”

    There is more to the book than the “field guide” portion. Like Darren said “A lengthy introductory section reviews dinosaur anatomy, biology, evolution, behaviour, and the climate, atmosphere and palaeogeography of the Mesozoic” is present in the book even though it’s more a summary than anything else.

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  27. 27. Therizinosaurus 7:45 pm 02/22/2012

    “Unfortunately, that’s perfectly fine with the ICZN.”

    Well, as Chris Taylor pointed out in my review of the book, the ICZN doesn’t care about reassignments of existing species to existing genera.

    “Is “September 30th” just a default derived from Art. 21.3.1?”

    Yes.

    “And has anybody seen both specimens?”

    Not that I know of. Scansoriopteryx was on a traveling exhibit, but is seemingly now back in Utah. Epidendrosaurus has been at the IVPP. I’d guess most paleontologists haven’t tried to see Scansoriopteryx, since they tend to ignore Czerkas’ taxa, but maybe they’ll see them and just not publish on them?

    “Does Paul have a cladistics background that I’m missing?”

    Paul actually used unweighted numerical cladistic analyses fairly early (e.g. his 1984 segnosaur paper), but has since considered it an unreliable way to determine phylogeny. While he used paraphyletic taxa in PDW, he now only uses them informally, so is a cladist in that sense. I think the bigger issue is that Paul’s a believer in Linnaean ranks. So a genus means something to him (apparently a certain range of morphological variation) and he tries to make that a constant within Tetrapoda. While most of the rest of us don’t care how extensive genera are as long as they’re monophyletic.

    “There is more to the book than the “field guide” portion.”

    Yeah, but an introductory summary to dinosaurs is hardly the “ultimate” Greg Paul writing, while DA is all about his most famous scientific hypothesis- secondarily flightless maniraptorans/iforms.

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  28. 28. Hydrarchos 9:44 pm 02/22/2012

    Apologies for this having nothing to do with dinosaurs or this book review, but I found this photo fairly randomly and thought it might be of interest to Darren Naish (and/or others here), as he has posted about really big snakes in the past.

    Assuming those humans are in the “normal” height range (I can’t identify the ethnic group or locality), the snake looks to me like it must be *at least* 7.5m, perhaps over 8m long. I’m guessing it’s one of the bigger pythons (molurus or reticulatus?) as the pattern’s all wrong for an anaconda. I don’t know anything about the source of the photo (it’s from one of those blogs where people post photos without comment or attribution) but maybe someone here has seen it before or has an idea where it’s from?

    (I couldn’t make the “contact” form on this blog work on my computer – it gave me a JavaScript error message…)

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  29. 29. JAHeadden 10:28 pm 02/22/2012

    While Paul accepts some forms of cladistic analysis, he seems to be opposed to the “cladistic ideology” of explicit clade formation and qualification through phylogenetic nomenclature. He uses the latter, but not the former (i.e., he defines his clades, but seems to prefer apomorphy-based stem clades, as it were = Averostra, etc.). I think Paul’s personal views of bird evolution and dinosaur arranegment are essentially typological, in that he actually weighs his taxa by degrees of “valuable” characters, with some holding more sway than others. This is how he qualifies his “gut”-based phylogenies in PDW and DA.
    He follows this with very little explanation in PFGD, which is the second big problem with the book.

    I can actually admire (and was impressed by) his argument in PDW that there can be some form of explicit criteria by which taxa can be split/lumped, but later became disillusioned because Paul never demonstrated his metric (the “genericometer”).

    Ok, that’s it with my Paul-bashing.

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  30. 30. Cameron McCormick 10:49 pm 02/22/2012

    Hydrarchos –

    It’s a 6.9 meter reticulated python and the men are Agta, so-called “Negritos” from the Philippines. The publication is available here.

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  31. 31. Dartian 3:35 am 02/23/2012

    David:
    But that was done as part of a great big phylogenetic revision. All the genera that replace Bufo in the traditional sense came out as monophyletic in the analysis by Frost et al. (2006) who did the taxonomic revision.

    Perhaps I misread Darren’s comment, but I interpreted him as suggesting that what’s mainly keeping people from splitting Varanus into several genera is reluctance to upset the traditional subgenus-level classification (and perhaps also a dislike of the idea of ending up with lots of monotypic varanid genera). That may be part of the explanation, but, as I pointed out, in some other squamate and lissamphibian groups, far more extensive and tradition-upsetting taxonomic changes have taken place with (seemingly) little serious protest. If ‘taxonomic inertia’ was insufficient to prevent the splitting of Lacerta or Bufo*, surely Varanus can be split too?

    * Or, indeed, the traditional Python genus, which perhaps is an even better analogue to the case of Varanus (among other similarities, extant Pythonidae and Varanidae have near-identical global distributions). Until just a couple of decades or so ago, Python, too, was super-inclusive; today, virtually everyone seems to agree that the various Australo-Papuan species need to be placed in several separate genera. (More taxonomic changes are surely on the way for the Paleotropical pythons, too – the reticulated python, for example, will probably be taken out of Python and placed in the genus Broghammerus instead.)

    Such an analysis still hasn’t been done for Varanus.”

    Well, I’m not entirely sure of what qualifies as a “great big” phylogenetic revision but there is, at least, this study:
    Ast, J.C. 2001. Mitochondrial DNA evidence and evolution in Varanoidea (Squamata). Cladistics 17, 211-226.

    Mickey/Therizinosaurus:
    most of the rest of us don’t care how extensive genera are as long as they’re monophyletic

    I hope you’re not suggesting that a majority of those contemporary taxonomists who use (or “believe in”) Linnaean ranks don’t care about whether their genera are monophyletic or not, because such an assertion would just be flat-out incorrect.

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  32. 32. naishd 4:49 am 02/23/2012

    One quick comment on the nomenclature used for Varanus and some of other extant taxa mentioned above: part of the reason that the splitting up of the traditional versions of Bufo, Lacerta etc. has been (mostly) welcomed comes from the fact that these entities are horribly paraphyletic. Varanus can be broken up into clades, of course, but the main reason people mostly aren’t using the proposed divisions is that there are no concerns about its monophyly (and, as I said above, the proposed ‘subgenera’ have been a bit unstable in phylogenies).

    Darren

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  33. 33. Dartian 5:34 am 02/23/2012

    Darren:
    the main reason people mostly aren’t using the proposed divisions is that there are no concerns about its monophyly

    There is no doubt about the monophyly of chameleons either. Should they all therefore be lumped into the genus Chamaeleo?

    Or, since alligators and caimans are undoubtedly monophyletic too, should Caiman, Melanosuchus and Paleosuchus therefore be merged into Alligator? If not, why not?

    (Mind you, I’m not trying to be a prat; those were earnest questions.)

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  34. 34. naishd 6:26 am 02/23/2012

    Dartian: I think a whole essay (or blog post) could be written on this issue – it concerns social inertia, what we consider useful, and subjective ideas of ‘distinctiveness’, ‘generic distances’ etc. All I’ll say for now is that Chamaeleo of tradition is paraphyletic with respect to the traditional ‘genus’ Brookesia, and that alligatorids include several additional genera that are so morphologically disparate with respect to the taxa you list (e.g., the nettosuchids) that they would screw with the idea of a consistent, super-inclusive Alligator should it be suggested.

    Darren

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  35. 35. Dartian 6:55 am 02/23/2012

    Darren:
    alligatorids include several additional genera that are so morphologically disparate with respect to the taxa you list (e.g., the nettosuchids) that they would screw with the idea of a consistent, super-inclusive Alligator should it be suggested

    If you think that (say) Purussaurus is morphologically too disparate with respect to other alligatorids to be lumped into Alligator (or even into Caiman), then do you also think that (say) Megalania is too morphologically disparate with respect to other varanids to be lumped into Varanus?

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  36. 36. naishd 7:00 am 02/23/2012

    Well, that’s a subjective issue of course.. but, personally, sinking Megalania into Varanus looks fine to me (it really isn’t that ‘distinct’ in terms of morphology), whereas the caimanines (including the nettosuchids) are easily ‘distinct enough’ to be kept separate from alligatorines. As I always say, it depends in any case on what the relevant community finds most useful.

    Darren

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  37. 37. Jerzy New 7:43 am 02/23/2012

    This Beipiaosaurus really has a fin, or it is uniformly long fur on the back getting clumped?

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  38. 38. Therizinosaurus 7:44 am 02/23/2012

    “I hope you’re not suggesting that a majority of those contemporary taxonomists who use (or “believe in”) Linnaean ranks don’t care about whether their genera are monophyletic or not, because such an assertion would just be flat-out incorrect.”

    Nope, not suggesting that at all. I honestly don’t know how many Linnaeists insist on monophyletic genera (there are very few in dinosaur paleontology), though I’d bet it’s lower than the percentage of non-Linnaeists who do.

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  39. 39. Dartian 8:31 am 02/23/2012

    Therizinosaurus:
    I honestly don’t know how many Linnaeists insist on monophyletic genera (there are very few in dinosaur paleontology), though I’d bet it’s lower than the percentage of non-Linnaeists who do.

    Well, considering that only a tiny, tiny minority of biological taxonomists specialise in Mesozoic dinosaurs, I would be careful with making generalisations of that kind. The reality is, of course, that the vast majority of biological taxonomists are still “Linneaists” – and that fact will not change anytime soon. Indeed, that fact shouldn’t change before that much-touted alternative (you know what I mean) has officially been launched.

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  40. 40. David Marjanović 9:01 am 02/23/2012

    While he used paraphyletic taxa in PDW, he now only uses them informally, so is a cladist in that sense.

    That has nothing to do with cladistics. Paul is the one known example of someone who uses phylogenetic nomenclature but doesn’t accept cladistics.

    part of the reason that the splitting up of the traditional versions of Bufo, Lacerta etc. has been (mostly) welcomed comes from the fact that these entities are horribly paraphyletic.

    …Oh yes. I should definitely have mentioned that. Bufo was paraphyletic with respect to almost all other bufonid genera, so the two possibilities for making all genera monophyletic were either to make Bufo and Bufonidae almost synonymous or to split the genus Bufo.

    It must have helped that the new genera are mostly identical with long-recognized species groups – Pseudepidalea was Bufo (viridis), Anaxyrus was Bufo (americanus) and so on. Similarly, raising the subgenera of Rana to genus status seems not to have been a big deal (though a bigger deal than splitting Bufo).

    Well, I’m not entirely sure of what qualifies as a “great big” phylogenetic revision but there is, at least, this study:
    Ast, J.C. 2001. Mitochondrial DNA evidence and evolution in Varanoidea (Squamata). Cladistics 17, 211-226.

    (Yay! I have access!!! :-) :-) :-) )
    It trashes all the traditional subgenera, leaving only Varanus (Odatria) mostly intact. Varanus (Varanus) even comes out as polyphyletic, as does Varanus (Empagusia).

    Maybe the biggest factor, socially speaking, is the fact that Ast herself only spent half a page out of 16 talking about subgenera and didn’t make any recommendations about how to split, say, V. (Varanus). What is the type species of V.? Ast doesn’t say! Is it V. salvator? If so, Megalania might be resurrected for the clade of V. komodoensis, V. salvadorii and V. varius… unless V. (Papusaurus), the monotypic subgenus for V. salvadorii, has priority. Or, of course, if M. prisca is actually closer to V. giganteus, the perentie, which is more closely related to V. (Odatria), the dwarf monitors, than to V. komodoensis.

    This Beipiaosaurus really has a fin, or it is uniformly long fur on the back getting clumped?

    Scroll back up to the photo and read what it says under it.

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  41. 41. Heteromeles 12:37 pm 02/23/2012

    Of course, if we had a time machine, and could do DNA analyses on the extinct members of extant genera, we’d probably find that almost every genus with extant and extinct members was paraphyletic. Allopatric speciation generally works by rendering clades paraphyletic, after all.

    (If this doesn’t make sense, here’s an example. There are three species in one genus, with A and B more closely related than C. The tree looks like (A,B),C. A small group of B gets washed to another island by one of those proverbial storms, and soon enough, that population is species D. (A,(B,D)),C. A bit thereafter, D is so morphologically distinct (perhaps it’s a tree, while A, B, and C are herbs), that everyone regards it as a separate genus. Nothing has changed with A, B, C on the mainland, but due to the evolution of D somewhere else, they are now paraphyletic.

    Yes, I’m being annoying. The point is that evolution happens in four dimensions (geography plus time) while phylogenies happen in two dimensions on paper. That inevitably leads to distortions. We should probably be a bit thoughtful when we rename things.

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  42. 42. Heteromeles 12:46 pm 02/23/2012

    On a more serious note, I can put out a plea to the systematists who are busy splitting up genera?

    If you have to create a new genus or specific epithet, especially for a living species, please make it something that sounds good.

    The reason is that many of these new species will need conservation, and it’s a lot easier to conserve things that have cool names.

    An example: I survey a little rare plant that used to be called Lotus nuttallianus. A few years ago, someone determined that the native Lotus in our area belong to the genus Acmispon, and Lotus nuttallianus became Acmispon prostratus. The researcher was stuck with Acmispon (it had priority, thanks to a stone-tongued researcher in the 1800s), but foolishly he proposed that the new common name should be Nuttall’s acmispon. That’s now propagating through all the databases that people use.

    Later this year, I’ve got to go in front of a City Council and tell them to save a pretty little beach flower, except that its name now sounds like a tropical disease. Acmispon prostratus. Way to go, systematist. I appreciate your support.

    If you’re giving a name to something, please make it a name that sounds like it’s worth saving. Okay? Think of the name as part of the future marketing campaign to save the species. We unwashed conservationists will thank you later.

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  43. 43. Jerzy New 5:20 pm 02/23/2012

    @Heteromeles
    You should be proud of London zoo, which renamed the mundane Panay Cloud Rat into poetic Panay Cloudrunner.

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  44. 44. Therizinosaurus 5:46 pm 02/23/2012

    “The reality is, of course, that the vast majority of biological taxonomists are still “Linneaists” – and that fact will not change anytime soon. Indeed, that fact shouldn’t change before that much-touted alternative (you know what I mean) has officially been launched.”

    You may be right that most biological taxonomists are Linnaeists, but in the sense I mean it, it has very little to do with using the IC(Z/B)N vs. the Phylocode. I don’t think the level of family really means anything, but I still strictly adhere to the ICZN when it comes to using taxa that end in -idae.

    “That has nothing to do with cladistics. Paul is the one known example of someone who uses phylogenetic nomenclature but doesn’t accept cladistics.”

    Cladistics is just classifying organisms based on shared derived characters. It doesn’t have to involve using unweighted numerical analyses to derive that classification.

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  45. 45. vdinets 12:01 am 02/24/2012

    Dartian: just for the record, Caiman apparently isn’t monophyletic unless Melanosuchus is lumped into it, so a few people (myself included) strongly support doing so.

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  46. 46. Dartian 1:54 am 02/24/2012

    Vladimir:
    “Caiman apparently isn’t monophyletic unless Melanosuchus is lumped into it

    I didn’t know that, interesting! Do you have a reference?

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  47. 47. Dartian 7:22 am 02/24/2012

    In partial response to my own inquiry, I noticed that Poe (1996) and Brochu (1999) have indeed published results of morphological (osteological) analyses that suggest the non-monophyly of Caiman. (Specifically, by recovering a sister-species relationship between Caiman latirostris and Melanosuchus niger.) Are these the studies you base your claim on, Vladimir?

    If so, there would seem to be some problems here. For starters, these particular results do not seem to be very strongly supported; the bootstrap support values for the Melanosuchus + C. latirostris clade are quite low, particularly in Brochu’s study. Furthermore, in Brochu’s study, that clade collapses when molecular data are included. Brochu says (p. 75): “Given the lack of support in the combined analysis, as well as the modesty of support from morphology alone, taxonomic revision is premature.” (Emphasis mine.)

    Additionally, a more recent, molecule-based study (Hrbek et al., 2008) does not recover a paraphyletic Caiman; according to this study, Melanosuchus niger is the sister taxon of a monophyletic Caiman. (Of course, a lumper could thus still argue for placing Melanosuchus in Caiman.)

    Now, I may well have missed some relevant studies, but based on those that I have found, it would seem to me that morphology offers only rather weak support for the notion that Caiman is paraphyletic, whereas molecules offer no support for it at all. Based on which data, precisely, do you think that the black caiman should be included in Caiman?

    References:
    Brochu, C.A. 1999. Phylogenetics, taxonomy, and historical biogeography of Alligatoroidea. Memoir (Society of Vertebrate Paleontology) 6, 9-100.

    Hrbek, T. Vasconcelos, W.R., Rebelo, G. & Farias, I.P. 2008. Phylogenetic relationships of South American alligatorids and the caiman of Madeira River. Journal of Experimental Zoology Part A: Ecological Genetics and Physiology 309A, 588–599.

    Poe, S. 1996. Data set incongruence and the phylogeny of crocodilians. Systematic Biology 45, 393-414.

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  48. 48. David Marjanović 9:28 am 02/24/2012

    If this doesn’t make sense, here’s an example.

    There’s a completely different reason why it doesn’t make sense the way you worded it: don’t say “clade” when you just mean “taxon”. Clades are by definition monophyletic, the definition being “an ancestor and all its descendants”; nothing can render a clade paraphyletic.

    In your example, phylogeneticists sooner or later figure out the tree you explain, and then they adjust the classification accordingly. DNA from extinct taxa would of course help, but it’s not as strictly necessary as you imply.

    its name now sounds like a tropical disease

    Come on. :-)

    but foolishly he proposed that the new common name should be Nuttall’s acmispon.

    Yeah… that doesn’t actually sound like a common name…

    Cladistics is just classifying organisms based on shared derived characters. It doesn’t have to involve using unweighted numerical analyses to derive that classification.

    They don’t have to be unweighted (and molecular ones commonly aren’t), but even Hennig himself made numerical analyses all the time.

    (Probably literally, because doing that stuff by hand takes a while or three.)

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  49. 49. Heteromeles 11:00 am 02/24/2012

    @David: the example I used was a paraphrase of a well-known case of adaptive radiation: the origin of Hawaiian silversword alliance (http://www.botany.hawaii.edu/faculty/carr/silversword.htm). There are trees on Hawaii that evolved from small herbaceous tarplants in California, and they are genetically similar enough that you can make a half tree, half weed hybrid. Such hybrids are sterile.

    The phenomenon is so well-known that Carlquist devoted 78 pages to a chapter on “Insular woodiness” in Island Biology (1974). He also devoted about 250 pages to adaptive radiation.

    AFAIK, the Hawaiian silversword alliance are well-embedded in the California tarplants, but no one is suggesting name changes in California or Hawaii to accommodate this relationship. They’re not useful. The silverswords are tetraploid relative to the tarplants, and are ecologically distinct from the tarplants.

    It also possible (though I don’t see the reference at darwin.uky.edu/~sargent/EvolutionFAQ/silverswords.pdf) that the silverswords arose from allotetraploid hybrids between two tarplant species. Like bread wheat, some of the silverswords can form (and possibly resulted from) intrageneric hybrids. It makes things rather complicated.

    So anyway, you were saying something about name changes? It might be useful to talk to some botanists first.

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  50. 50. Lars Dietz 11:24 am 02/24/2012

    David: The type species of Varanus is V. varius, according to this, which also has synonymies for all the varanid “subgenera”. Maybe some of these synonyms will have to be resurrected.
    Heteromeles: When I saw the name “Acmispon” I immediately thought “this looks like a Rafinesque name!” Googling showed I was right. His names usually do sound better than that, but something about the name just looked typical for him. Anyway, if you coin a few thousand generic names like Rafinesque did, a few of them probably are going to sound bad. (For those interested, the name is supposed to mean “point hooked”.)

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  51. 51. Heteromeles 12:38 pm 02/24/2012

    Thanks Lars. I hadn’t taken the time to track that one down. The “hook tip” is from the shape of the fruit according to the new Jepson Manual.

    The point I was trying to make still stands: nowadays, names matter to more than systematists. I’ve been surprised at the number of modern systematists I’ve run into who regard naming as their sacred privilege and private sport, and the rest of the world has to lump it with whatever they come up with. That’s a workable attitude when dealing with fossils and museum specimens, but if you want to help conserve the group you’re working on, give them names that sound good and/or meaningful.

    We can giggle at the Panay Cloudrunner, but if that gets more Philippinos to want it to stay alive, so much the better. The world doesn’t need more species like the human folly butterfly (Philotes sonorensis extinctus).

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  52. 52. naishd 2:23 pm 02/24/2012

    I agree with Heteromeles. Within recent months a long-running dispute has been unfolding in the Bulletin of Zoological Nomenclature over the name of the Aldabran giant tortoise. Some purists are insisting that Dipsochelys dussumieri is the correct name, whereas a larger number of ecologists, conservationists and so on are saying that we should stick with Aldabrachelys gigantea – not necessarily because it has technical precedence, but partly because it’s the name used throughout the conservation literature, the one involved in policy formation etc. The latter considerations should trump the one about nomenclatural precedence.

    Darren

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  53. 53. Jerzy New 7:39 pm 02/24/2012

    @heteromeles
    Recently I saw it named panay cloud rat again, so apparently the name change did not have the desired effect.

    I completely agree with your view that names function mainly for clear identification of things, so in changing them science should balance practical usefulness vs taxonomic opinions.

    BTW, some time ago I argued that the name Drosophila melanogaster is too embedded in genetics and biotechnology as a standard small animal, so entomologiss who wished to change it to Sophophora will be plainly ignored.

    So this week I walked past the local university and saw a conference with several lectures about genetics and development of …yes, Drosophila.

    :)

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  54. 54. Jerzy New 7:46 pm 02/24/2012

    @Heteromeles
    Thanks for silversword pictures. Really bizarre hybrids! Remember me douc langur x proboscis monkey hybrid.

    Link to this
  55. 55. David Marjanović 2:04 pm 02/26/2012

    I agree with Heteromeles. Within recent months a long-running dispute has been unfolding in the Bulletin of Zoological Nomenclature over the name of the Aldabran giant tortoise. Some purists are insisting that Dipsochelys dussumieri is the correct name, whereas a larger number of ecologists, conservationists and so on are saying that we should stick with Aldabrachelys gigantea – not necessarily because it has technical precedence, but partly because it’s the name used throughout the conservation literature, the one involved in policy formation etc. The latter considerations should trump the one about nomenclatural precedence.

    Indeed, petitions to the ICZN to conserve widely used junior synonyms often succeed. If it hasn’t happened yet, someone should submit one to the Bulletin of Zoological Nomenclature.

    …although… those are the same people that refused to change the type species of Drosophila to D. melanogaster. Hey, Sophophora, “wisdom-bearer”, isn’t a bad name, is it?

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  56. 56. Dartian 2:31 am 02/27/2012

    Darren:
    it’s the name used throughout the conservation literature, the one involved in policy formation etc.

    Not to dispute the more general point you made (which I basically agree with), but surely this particular case you chose as an example is much more complex than that? I mean, how firmly established is the name Aldabrachelys gigantea in the literature, really? It’s my (non-specialist’s) impression that the nomenclature and the taxonomy of the Indian Ocean giant tortoises are quite messy issues.

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  57. 57. Christopher Taylor 3:56 am 02/27/2012

    If it hasn’t happened yet, someone should submit one to the Bulletin of Zoological Nomenclature.

    I believe a petition on this subject has been submitted, and is currently under consideration (if it hasn’t been resolved already). Last I saw, letters had been printed in the Bulletin of Zoological Nomenclature arguing both for and against the petition.

    Personally, I see complaints like this about taxonomic changes not as a problem with the taxonomic process, but a problem with basing conservation on lists of protected species.

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  58. 58. David Marjanović 8:31 am 02/27/2012

    basing conservation on lists of protected species

    As opposed to areas/ecosystems?

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  59. 59. Heteromeles 11:02 am 02/27/2012

    re:basing conservation on lists of protected species as opposed to areas/ecosystems.

    Here’s the problem: the only “weapon” we in the US have is the Endangered Species Act, and similar legislation such as CITES. Note these laws give priority to species (and in the case of the ESA, subspecific taxa). There are massive problems with the ESA, but there is also powerful opposition to it in the US, and if we open it for amendment, we’re likely to lose it altogether. Given the situation, we’ll keep working with it as written.

    The ESA is the stick that allows conservation groups and agencies to dangle a carrot in front of landowners, so that the landowners will sell their high quality wildlands to government or conservation groups, rather than develop them. Without the costs and legal issues associated with the ESA, most landowners would sell to developers. They may want to save their lands, but if they have health issues and their kids want to be rich, it’s really hard to persuade them to not develop their land. The ESA raises the development cost of the land high enough that keeping it wild can be a reasonable fiscal alternative.

    The bottom line is that, like it or not, species have a legal definition. Worse, designation of a new species of living vertebrate or plant almost always has legal repercussions, because a new species is almost by definition rare, or it would have been named years ago. The only common, unknown vertebrates live in the deep ocean.

    I know that many systematists already know this, but a surprising number apparently do not. Personally, I hope that everyone training live-animal systematists will require their students to take conservation biology and/or environmental law, so that they understand the legal ramifications of their work.

    At Rancho Santa Ana Botanic Garden, they offer a course in which grad students create conservation plans for rare plants that lack these documents, and each student does a separate plant. It would be wonderful if more schools created such courses, because RSABG has done quite a bit of conservation work that way.

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