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Ryan et al.’s New Perspectives on Horned Dinosaurs: a review

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


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It says something of the invigoration of dinosaur research that an enormous technical tome, 624 pages long and containing 36 chapters, could be produced on horned dinosaurs (or ceratopsians) alone. New Perspectives on Horned Dinosaurs, published in 2010 and edited by Michael Ryan, Brenda Chinnery-Allgeier and David Eberth, stems from the Royal Tyrrell Museum Ceratopsian Symposium, held at Drumheller, Alberta, in September 2007. The organisers of this meeting were inspired by the major upsurge in horned dinosaur research currently underway – it involves the description of new taxa, a renewed interest in anatomy, behaviour and functional morphology, and the application of new techniques to such areas as the mechanical behaviour of bone, niche partitioning, phylogeny, biogeography and ontogeny.

Despite the popular name, not all horned dinosaurs are horned. Ceratopsia in fact includes psittacosaurids (a group of Asian bipedal forms, the skulls of which are often superficially likened to those parrots), the deep-headed, hornless leptoceratopsids, an assemblage of small- to medium-sized, mostly quadrupedal forms that were once grouped together as protoceratopsids (they have bony frills, and some, like the eponymous Protoceratops, have short or incipient nasal horns), and the members of the large-bodied, horned Zuniceratops + ceratopsid clade*. Ceratopsidae includes both the mostly long-frilled chasmosaurines with their long supraorbital, postorbital or brow horns, and the mostly short-frilled centrosaurines with their long nasal horns and typically short (or absent) postorbital horns. Zuniceratops and several other fossils seem to show that postorbital horns are primitive for the Zuniceratops + Ceratopsidae clade. Protoceratops, ceratopsids and their frill-headed kin (that is, all ceratopsians closer to Triceratops than to Psittacosaurus) are united within Neoceratopsia, while the node-based clade that includes Protoceratops and Triceratops is termed Coronosauria (Sereno 1998). [Highly simplified cladogram below borrowed from Thomas R. Holtz's University of Maryland lecture notes. Version below is low-res, pdf here has far better resolution.]

Simplified cladogram of Ceratopsia (and other members of the ornithischian clade Marginocephalia), compiled by Thomas R. Holtz using skeletal reconstructions by Greg Paul and others. Follow link above for higher-res version.

* There’s no name for the node-based clade that includes Zuniceratops, Ceratopsidae, and all descendants of their common ancestor. However, the names Ceratopsoidea and Ceratopsomorpha both apply to the branch-based clade that includes all taxa closer to Triceratops than to Protoceratops (Sereno 1998, Wolfe & Kirkland 1998). Ceratopsoidea has been used more frequently in the literature than Ceratopsomorpha and this is the best name we have at the moment for the “Zuniceratops + Ceratopsidae clade”.

New Perspectives on Horned Dinosaurs consists of five sections: overview; systematics and new taxa; anatomy, functional biology and behaviour; phylogeny, biogeography, taphonomy and palaeoenvironment; and the history of collecting. The bulk of the book is made up of the second and third sections. The first section includes but a single article, and the last section includes just two. Virtually all contributions are very well illustrated and there is even a colour plate section. The book is large-format (c. 29 x 22 cm) and hence very different from most of the other multi-authored dinosaur-themed volumes published by Indiana University Press.

Homage to Prof. Dodson: “40 years of Ceratophilia”

Prof. Peter Dodson, professor of anatomy and paleontology at University of Pennsylvania, here holding the skull of Auroraceratops rugosus.

The quality throughout is high and most students of the Ceratopsia were evidently compelled to contribute interesting work. Some articles do stand out as especially interesting, strong, or both.

Peter Dodson’s opening article (the single contribution in section one) – ‘Forty years of Ceratophilia’ – provides an excellent, personal overview of ceratopsian studies of the past four decades. Dodson says that his apparent modern role as “the dean … of ceratopsian studies” (Dodson 2010, p. 3) is a sort of happy accident; we know, in fact, that he is deserving of this role, having led work on the group through innovation, excellent research and brilliant writing (Dodson 1996). The ‘genealogy of Dodson ceratopsian students’ is a really nice touch, paralleling the efforts of other palaeontologists to produce phylogenies of academic ‘relatedness’. [Adjacent image of Dodson from his blog.]

Among other articles that really stand out, Dodson, You and Tanoue’s article on the basicranium and palate anatomy of psittacosaurids and non-ceratopsid neoceratopsians includes some wholly new anatomical information. Scott Sampson and Mark Loewen’s chapter is an excellent review of ceratopsid biogeography and phylogeny. One of their main conclusions – perhaps surprising to those who think that there might now be too many ceratopsids in Late Cretaceous North America! – is that “diversity will increase greatly once less explored geographic regions and temporal intervals are subject to greater sampling” (Sampson and Loewen 2010, p. 423). Indeed, as anyone who’s even vaguely aware of horned dinosaur diversity will know, a surprising number of new (mostly North American) taxa have been named within the last few years.

Those many, many new taxa

The volume itself includes the names of no fewer than six new taxa (one of which represents a renaming, not a wholly new taxon).

Awesome life restoration of Coahuilaceratops magnacuerna, by Lukas Panzarin. Lukas's horned dinosaurs (and other ornithischians) are easily among the best and most accurate dinosaur life restorations ever produced.

Coahuilaceratops magnacuerna Loewen et al., 2010 is a new chasmosaurine from the Cerro del Pueblo Formation of Mexico, notable for its gigantic, massively robust postorbital horncores, among the largest of any ceratopsian. Phylogenetic analysis recovers it as a close relative of Anchiceratops and Arrhinoceratops (Loewen et al. 2010) (though see Sampson et al. 2010). The second new taxon, Diabloceratops eatoni Kirkland and Deblieux, 2010, is a new brow-horned centrosaurine from the Wahweap Formation of Utah, named for a spectacular skull. Its nasal horn is tiny, the epijugal processes on the cheeks are especially long, and slender, outwardly curved epoccipitals are present at the posterior edges of the parietals. As noted above, we would predict that centrosaurines began their history with short nasal horns and long brow horns: nevertheless, it is good to have this confirmed in the form of both Diabloceratops and the also recently described Albertaceratops. The authors report a second specimen that seems to represent a second, as-yet-unnamed Diabloceratops species.

Wonderful life restoration of Rubeosaurus by Lukas Panzarin, licensed under Creative Commons Attribution 2.5 Generic license.

Rubeosaurus McDonald & Horner, 2010 is the new generic name for the centrosaurine previously known as Styracosaurus ovatus. While the inclusion of this Upper Two Medicine Formation taxon in Styracosaurus had never previously been challenged (see Ryan et al. 2007), it is not, in fact, a close relative of Styracosaurus proper (S. albertensis) if new phylogenetic studies are to be believed. In fact it is closer to Einiosaurus within the pachyrhinosaur lineage. Today it seems all too easy to forget that, just 20 years ago, Pachyrhinosaurus canadensis was regarded as the sole representative of a peculiar and otherwise enigmatic centrosaurine lineage.

One of the first papers to report new pachyrhinosaurine taxa – Horner et al. (1992) – made news at the time by proposing that Styracosaurus, Rubeosaurus, Einiosaurus, Achelousaurus and Pachyrhinosaurus belonged to an anagenetic lineage, the evolution of which was ‘forced’ by a marine transgression that caused ‘habitat bottlenecking’ and consequent intense selection pressure and rapid evolution. McDonald & Horner (2010) note that this hypothesis is not redundant altogether since rapid evolution and the displacement effects of the marine transgression both seem to have occurred; nevertheless, new species and new studies seem to show that cladogenesis was occurring instead or in addition. Indeed, yet another member of the pachyrhinosaur lineage is described in another of the volume’s chapters. It’s an unnamed form from the Upper Dinosaur Park Formation. Given that it likely represents a new species of Pachyrhinosaurus, this clade alone (that is, Pachyrhinosaurus) now includes four species.

Skull reconstruction of Ojoceratops fowleri, incorporating both holotype squamosal and referred elements, produced by Robert Sullivan. Available under Creative Commons CC0 1.0 Universal Public Domain Dedication, from wikipedia.

Ojoceratops fowleri Sullivan & Lucas, 2010 is named for a left squamosal from the Ojo Alamo Formation of New Mexico’s San Juan Basin, identified as that of a Triceratops-like chasmosaurine. Already it has been suggested that O. fowleri may in fact be synonymous with Triceratops (Longrich 2011). One peculiarity of Sullivan & Lucas’s (2010) terminology is their use of ‘crown chasmosaurine’ (p. 177). Another new chasmosaurine – Medusaceratops lokii Ryan et al., 2010 – is named for parietal fragments from the Judith River Formation of Montana, originally referred to the centrosaurine Albertaceratops. Large, robust postorbital horns from the same bonebed are inferred to belong to it. Medusaceratops is the oldest reported chasmosaurine.

Skull reconstruction of Tatankaceratops sacrisonorum (from Ott & Larson 2010), with (B) showing it superimposed on the skull of Triceratops horridus.

Then there’s Tatankaceratops sacrisonorum Ott & Larson, 2010 from the Hell Creek Formation of South Dakota. The existence of a new chasmosaurine in the late Maastrichtian of western North America is interesting in view of debates about dinosaur diversity at this time and place, and it is inevitable that some will immediately identify the type and only specimen as a juvenile Triceratops (as anyone interested in dinosaurs will know all too well, debate continues as to whether some or all late Maastrichtian chasmosaurines represent distinct taxa, or growth stages of the same species). However, Tatankaceratops has proportionally short, subvertical postorbital horns that look different from both the far longer, posteriorly curving horns present in juvenile Triceratops and the even longer, anteriorly curving horns present in adult Triceratops (Horner & Goodwin 2006). The possibility that it might represent a dwarf form of Triceratops (Longrich 2011) appears plausible, as does the suggestion that it could be an aberrant individual. These ideas could perhaps be tested via histological analysis.

A new species of Archaeoceratops, A. yujingziensis, is also named in the volume. A redescription of the Montanoceratops cerorhynchus holotype and a new report of Prenoceratops from the Oldman Formation add new data points to the growing body of literature on leptoceratopsids.

Spinops sternbergorum, restored by Dmitry Bogdanov.

I should finish this discussion of new taxa by noting that descriptions of new horned dinosaur taxa have not exactly been restricted to this volume. Since this book has appeared, North America has yielded the additional new centrosaurine Spinops sternbergorum Farke et al., 2011 as well as the new chasmosaurines Utahceratops gettyi Sampson et al., 2010 and Kosmoceratops richarsoni Sampson et al., 2010. The new name Vagaceratops Sampson et al., 2010 has been given to the taxon originally described as Chasmosaurus irvinensis, and the somewhat controversial Mojoceratops perifania Longrich, 2010 and Titanoceratops ouranos Longrich, 2011 have also been named. Then there’s the Asian centrosaurine Sinoceratops zhuchengensis Xu et al., 2010, the new leptoceratopsids Zhuchengceratops inexpectus Xu et al, 2010, Gryphoceratops morrisoni Ryan et al., 2012 and Unescoceratops koppelhusae Ryan et al., 2012 and the protoceratopsid-grade taxa Ajkaceratops kozmai Ősi et al., 2010 and Koreaceratops hwaseongensis Lee et al., 2011.

Chasmosaurine phylogeny (showing positions of the 2010 taxa Utahceratops and Kosmoceratops) from Sampson et al. (2010). From PLoS ONE, licensed under Creative Commons Attribution License.

CMN 8547, mounted with a replica Anchiceratops skull. Photo courtesy of ReBecca Hunt-Foster.

One of my favourite chapters is Jordan Mallon and Robert Holmes’s description of CMN 8547, a near-complete chasmosaurine specimen (mounted at Ottawa’s Canadian Museum of Nature with a replica Anchiceratops skull), conventionally assigned to Anchiceratops due to the association of some supposedly diagnostic frill fragments. It turns out that those fragments aren’t all that diagnostic and that the taxonomic status of the specimen is uncertain. This is unfortunate (and needs resolving) since CMN 8547 is such a beautifully preserved, near-complete specimen. Its robust build, massive limbs and short tail are peculiar features that might suggest a hippo-like lifestyle.

Horns, frills, herding and lifestyle… a few unorthodox ideas

What of behaviour and ecology? The diverse and often spectacular horns, frills and other cranial structures present in the group have of course invited substantial speculation on social behaviour, sexual selection, the need to deal with contemporaneous theropods, thermoregulation and even acoustics. Needless to say, there is a huge amount of information here that will be of interest to those investigating horned dinosaur ecology, behaviour and palaeoenviromental preferences. Chapters include David Krauss and colleagues’ on the correlation between horn and frill morphology in chasmosaurines (parietal fenestrae are positioned just outside horn reach), Donald Henderson’s on niche partitioning as indicating by skull shape, and Rebecca Hunt and Andrew Farke’s on behavioural information as inferred from bonebeds. They conclude that, while there is good evidence for herding behaviour in some taxa, the evidence is not so good that we should make assumptions about herding across the clade.

Skull of Protoceratops andrewsi (though this one is without the sclerotic rings you need to determine eye size). Photo by Jordi Payà, from wikipedia.

Two behaviour-themed articles in particular stand out as unusual, and indeed the editors note in the preface that they are “sure to spark debate” (Ryan et al. 2010, p. xiii). Nick Longrich uses data from sclerotic ring size to propose that the unusually large-eyed Protoceratops might have been scotopic (or nocturnal). Given the abundance of specimens and quality of preservation, surprisingly little has been published on the palaeobiology of Protoceratops. Most work has concentrated on the supposed presence of sexual dimorphism and on the nests and eggs associated (sometimes incorrectly) with this dinosaur; its probable diet and habits have not been well explored. Schmitz & Motani (2011) used a similar technique to Longrich (2010) to analyse possible activity patterns in dinosaurs and other Mesozoic archosaurs, though did not report the same conclusions for Protoceratops. While this angle of analysis looks promising, already there are uncertainties given that Microraptor – inferred from eye form to be scotopic – is known to possess glossy feathers, a feature never present in extant scotopic species (Li et al. 2012). [Adjacent photo by Jordi Payà, licensed under Creative Commons Attribution-Share Alike 2.0 Generic license.]

Psittacosaurus preserved alongside the turtle Manchurochelys - proof of aquatic habits in a psittacosaurid! (irony). Image by Christopher, Tania and Isabelle Luna, from wikipedia (uploaded by FunkMonk). Released under Creative Commons Attribution 2.0 Generic license.

In the second ‘unusual’ chapter, Tracy Ford and Larry Martin put forward the surprising (but not wholly novel) proposal that Psittacosaurus was amphibious. The evidence used to support this idea is underwhelming; none of the features they point to are reliable indicators of aquatic habits. They make vague and unconvincing comparisons between the psittacosaurid forelimb and that of sea-turtles, cetaceans and other swimmers, imply that flexible hindlimb joints provide evidence for a swimming habit, suggest that gastroliths may have been present because of a role in buoyancy control, and draw attention to the presence of a laterally compressed tail skeleton and dorsally placed nostrils and orbits. [Adjacent photo by Christopher, Tania and Isabelle Luna]. Most or all of these features either do not link consistently with swimming habits, or are clearly present in other animals that do not, or did not, regularly swim. Their suggestion that the long bristle-like tail structures seen in one psittacosaurid specimen “may have supported a caudal fin that was somewhat analogous to the caudal fin in modern amphibians, such as the Hellbender … and tadpoles” is surprising (Ford & Martin 2010, p. 335). I’m not sure that it’s completely untenable, but the very slender, often overlapping fibres on the psittacosaurid tail clearly seem to be external to the epidermis, not sandwiched within it (as they’d have to be if they were within a continuous skin frill or fin). And, so… we have this vision (below, courtesy of Zach Miller of When Pigs Fly Returns).

Imaginatively restored aquatic psittacosaurid, by Zach Miller. Used with permission.

That famous psittacosaurid with the quilly tail - so far the only one known to have these structures (from Mayr et al. 2002). Did I ever say that Naish & Martill (2001) were just about the first to illustrate this specimen? Yeah, like that means something. And I do use the term "illustrate" rather loosely...

As David Eberth points out in his review of palaeoenvironmental associations and taphonomy, the unusually high number of fully articulated psittacosaurid specimens suggests that their carcasses did not endure a lengthy ‘bloat-and-float’ phase prior to burial, an observation apparently at odds with Ford and Martin’s model. Nevertheless, the idea is not so bizarre that it can be dismissed entirely without consideration. As the authors note, the proposal may not apply to all psittacosaurid species, and we have to keep in mind the ecological and behavioural diversity seen in certain extant ‘genera’. Furthermore, amphibious habits should not be ruled out entirely for all ceratopsians. The good news is that we have so many psittacosaurid specimens that testing this hypothesis would be very simple, should someone feel it worthy of proper investigation.

An accompanying CD ROM includes two lengthy contributions that would not have worked well as published articles but are worth having for completists: Tracy Ford’s stratigraphically arranged specimen list, and Darren Tanke’s substantial, date-arranged compilation of discoveries, events and biographies relevant to horned dinosaur research in Alberta.

All in all, New Perspectives on Horned Dinosaurs is arguably the most significant dinosaur book to appear in recent years, and this is against a lot of competition. It demonstrates – just in case there was any doubt – that feathered maniraptorans and tyrannosaurids are not the only sections of the dinosaur tree where exciting research and discoveries are happening. In term of density, significance, novelty and sheer volume of content, and in the quality of the text and illustrations, it’s outstanding – certainly head and shoulders above the many other dinosaur-themed volumes published by Indiana University Press. It does a superb job of capturing the status of horned dinosaur research at it was in the first decade of the present century. Surely, with this much exciting research and investigation underway, there are many surprises yet to come.

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. Hardback, index, refs, pp. 624. ISBN 978-0-253-35358-0. Here on Amazon, here on Amazon.co.uk.

There’s now quite a lot on Tet Zoo about horned dinosaurs. For previous articles, see…

Refs – -

Dodson, P. 1996. The Horned Dinosaurs. Princeton University Press, Princeton, NJ.

- . 2010. Forty years of Ceratophilia. 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, pp. 3-13.

Ford, T. & Martin, L. D. 2010. A semi-aquatic life habit for Psittacosaurus. 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, pp. 328-339.

Horner, J. R. & Goodwin, M. B. 2006. Major cranial changes during Triceratops ontogeny. Proceedings of the Royal Society, London B 273, 2757-2761

- ., Varricchio, D. J. & Goodwin, M. B. 1992. Marine transgressions and the evolution of Cretaceous dinosaurs. Nature 358, 59-61.

Li, Q., Gao, K.-Q., Meng, Q., Clarke, J. A., Shawkey, M. D., D’Alba, L., Pei, R., Ellison, M., Norell, M. A. & Vinther, J. 2012. Reconstruction of Microraptor and the evolution of iridescent plumage. Science 335, 1215-1219.

Loewen, M. A., Sampson. S. D., Lund, E. K., Farke, A. A., Aguillón-Martínez, M. C., De Leon, C. A., Rodríguez-De La Rosa, R. A., Getty, M. A. & Eberth, D. A. 2010. Horned dinosaurs (Ornithischia: Ceratopsidae) from the Upper Cretaceous (Campanian) Cerro del Pueblo Formation, Coahuila, Mexico. 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, pp. 99-116.

Longrich, N. R. 2010. The function of large eyes in Protoceratops: a nocturnal ceratopsian? 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, pp. 308-327.

- . 2011. Titanoceratops ouranos, a giant horned dinosaur from the Late Campanian of New Mexico. Cretaceous Research 32, 264-276.

Mayr, G., Peters, D. S. & Plodowski, G. 2002. Bristle-like integumentary structures at the tail of the horned dinosaur Psittacosaurus. Naturwissenschaften 89, 361-365.

McDonald, A. T. & Horner, J. R. 2010. New material of “Styracosaurus” ovatus from the Two Medicine Formation of Montana. 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, pp. 156-168.

Naish, D. & Martill, D. M. 2001. Boneheads and horned dinosaurs. In Martill, D. M. & Naish, D. (eds) Dinosaurs of the Isle of Wight. The Palaeontological Association (London), pp. 133-146.

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.

- ., Chinnery-Allgeier, B. J. & Eberth, D. A. 2010. Preface. 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, pp. xiii-xiv.

Sampson, S. D. & Loewen, M. A. 2010. Unravelling a radiation: a review of the diversity, stratigraphic distribution, and evolution of horned dinosaurs (Ornithischia: Ceratopsidae). 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, pp. 405-427.

- ., Loewen, M. A., Farke, A. A., Roberts, E. M., Forster, C. A., Smith, J. A. & Titus, A. L. 2010. New horned dinosaurs from Utah provide evidence for intracontinental dinosaur endemism. PLoS ONE 5(9): e12292. doi:10.1371/journal.pone.0012292

Schmitz, L., & Motani, R. (2011). Nocturnality in Dinosaurs Inferred from Scleral Ring and Orbit Morphology Science, 332 (6030), 705-708 DOI: 10.1126/science.1200043

Sereno, P. C. 1998. A rationale for phylogenetic definitions, with application to the higher-level taxonomy of Dinosauria. Neues Jahrbuch für Geologie und Paläontologie, Abhandlungen 20, 41-83.

Sullivan, R. M. & Lucas, S. G. 2010. A new chasmosaurine (Ceratopsidae, Dinosauria) from the Upper Cretaceous Ojo Alamo Formation (Naashoibito Member), San Juan Basin, New Mexico. ). 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, pp. 169-180.

Wolfe, D. G. & Kirkland, J. I. 1998. Zuniceratops christopheri n. gen. & n. sp., a ceratopsian dinosaur from the Moreno Hill Formation (Cretaceous, Turonian) of west-central Montana. New Mexico Museum of Natural History and Science Bulletin 14, 303-317.

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. Heinrich Mallison 3:43 am 04/8/2012

    I have but one gripe with this volume: 2007 –> 2012 is way too long! That’s very likely in part the fault of the American Misinvestment Crisis, and I experienced it in a lesser way with my contributions to the Sauropod Biology volume, too.

    Oh, and another gripe: I ordered a lot of book recently from IUP, but this any many other interesting volumes weren’t available just yet. Bleh!

    Link to this
  2. 2. naishd 5:44 am 04/8/2012

    To those interested.. Tracy Ford and I have exchanged a few messages on facebook, have asked him to post comment here. I don’t agree with Ford & Martin’s hypothesis, but I’m pleased that they published it.

    Darren

    Link to this
  3. 3. VDog3EK0!uNz 3:12 pm 04/8/2012

    I really do not mean to be dismissive… If the climate radically changed in the future to favor habitats for horned lizards, so that they became huge and greatly varied, what would be the difference?

    Link to this
  4. 4. MikeTaylor 4:16 pm 04/8/2012

    Excellent review of a book that I now feel stupid for not having bought when it was on special offer direct from IUP. Darn.

    One thing: I notice that your Amazon links at the end are not affiliate links. It’s probably well worth your while to make affiliate accounts: back when I was reviewing programming books on The Reinvigorated Programmer I was getting $50-$100 per month in affiliate fees.

    Link to this
  5. 5. Therizinosaurus 5:27 pm 04/8/2012

    Is there any extensive online geneology of paleontology students?

    Link to this
  6. 6. VDog3EK0!uNz 6:40 pm 04/8/2012

    That really was not a rhetorical question.

    Link to this
  7. 7. naishd 6:05 am 04/9/2012

    Thanks indeed for comments.

    Mike (comment 4): I did set up an amazon affiliates account a while ago, but have never made a single penny, thus can’t be bothered.

    Darren

    Link to this
  8. 8. naishd 6:15 am 04/9/2012

    Therizinosaurus (comment 5): I’ve now seen something like four different ‘phylogenies’ for vertebrate palaeontologists. (1) There’s the published Dodson one, (2) Tom Kemp showed one of Cambridge researchers at the ‘Sea Dragons of Avalon’ 2009 seminar, (3) via email, I’ve seen one compiled in California, linking researchers back to Osborn and Cope, and (4) I believe Don Henderson compiled one, incorporating as many researchers as possible. If anyone knows of others, please say so. I can’t see that any of these are available online.

    VDog3EK0!uNz: can’t really see what you’re getting at. Modern horned lizards are lizards, they aren’t dinosaurs, and there are no indications that they might end up looking like horned dinosaurs, given a hypothetical evolutionary trajectory. Maybe you’d be interested in the Squamozoic project :)

    Darren

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  9. 9. David Marjanović 9:38 am 04/9/2012

    I really do not mean to be dismissive… If the climate radically changed in the future to favor habitats for horned lizards, so that they became huge and greatly varied, what would be the difference?

    First, ceratopsians aren’t lizards. Just… look at their skeletons. It’s completely obvious that they’re not lizards. It’s not just the size and the horns; I don’t even know where to begin.

    Second, how can a habitat be for something horned? Horns hardly depend on the environment, they’re mostly products of sexual selection.

    If anyone knows of others, please say so.

    I’d love to see them, too. There’s always the Ostromidae (continued here). I once put a page about my own lineage together, but I no longer have any webspace; let’s see if I find it on my harddisk…

    Aaaah yeah. Huxley, Osborn, Gregory, Romer, Carroll, Reisz, Laurin, self. Other Laurin graduates (doctorate only): Damien Germain, Aurore Canoville; other Reisz graduates: David Dilkes, IIRC Johannes Müller, Linda Tsuji; other Carroll graduates: Jason Anderson, Philip Currie; Anderson graduates: Jennifer Olori, Hillary Maddin, Taran Myers, and I think Jason Pardo. I know most of this from Michel.

    Also, You and Martin taught Jacobs, who taught Kobayashi; Martin also taught Zhou Zhonghe. I must have found that on the DML somewhere, but can’t find the source.

    Was Cope a Huxley student?

    Link to this
  10. 10. llewelly 1:19 pm 04/9/2012

    I had thought Cope was a student of Joseph Leidy (the character who argued some early, nearly complete hadrosaur was a biped)

    Wikipedia seems to confirm this – or maybe it only means he took anatomy from Leidy, I can’t tell.

    Link to this
  11. 11. VDog3EK0!uNz 2:15 pm 04/9/2012

    What is the closest present day analogue to a ceratopsian? What creature would be most likely to evolve into something like a ceratopsian in the future given the necessary conditions?

    Link to this
  12. 12. A.Bonnin 2:47 pm 04/9/2012

    “What is the closest present day analogue to a ceratopsian?”

    Answer: a bovid

    “What creature would be most likely to evolve into something like a ceratopsian in the future given the necessary conditions?”

    Answer: a bovid

    What a strange, strange, strange line of inquiry. Are you deliberately being strange?

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  13. 13. VDog3EK0!uNz 4:25 pm 04/9/2012

    No. Climate may be cyclical and then evolution would necessarily be to some degree cyclical. There is a very good possibility that climate is cyclical. This question has received very serious treatment by William James Burroughs in his Cambridge University Press book, Weather Cycles: Real or Imaginary (Second edition 2003).

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  14. 14. A.Bonnin 6:46 pm 04/9/2012

    What. The. Hell?? Even if this is true (that climate is cyclical) what does it have to do with lizards evolving into dinosaur-like animals? evolution does not run to some sort of inevitable plan. I mean, there is no reason to think that animals mimicking horned dinosaurs would ever evolve again.

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  15. 15. Heteromeles 9:08 pm 04/9/2012

    VDog3EK0!uNz: What kind of dinosaur do you personally mimic? That’s what your logic says. If evolution runs in circles, you’re mimicking a dinosaur. The problem is that evolution doesn’t run in cycles. Worse than that, during the first three billion plus years of life on Earth, there were nothing but bacteria present. Animal life on land is around 400 million years old (that’s less than the last 10% of Earth’s history) so if evolution is cyclical, you’re currently mimicking a bacteria. Just as those ceratopsians were. Do you begin to see how ridiculous the whole idea of circular evolution is?

    Here’s another example. As Darren noted in the previous blog entry, it’s quite possible that there was glaciation during the Mesozoic, and it’s certain that there was glaciation both before and after that. This does NOT mean that there were things like Neanderthals or woolly mammoths in the early Cretaceous, nor back in the Carboniferous. Mammoths and Neanderthals only showed up during the last Ice Age, and none of them mimic any dinosaur.

    Nor do you.

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  16. 16. llewelly 11:00 pm 04/9/2012

    The word evolution occurs exactly once in the book to which you refer. I doubt the book says anything about cyclic evolution.

    While there are many cyclic forces on climate, such as the changes in the shape of Earth’s orbit, and the angle of its axis of rotation (known collectively as Milankovitch cycles), there are also many acyclic forces on climate, such as human emissions of green houses gasses, continental drift, and so on. Note in particular continental drift; evolution is affected primarily by local climate, not global climate, and local climates are strong affected by continental drift.

    But the most serious flaw in the notion of cyclic evolution is the fact that evolution is inherently destructive; lineages must die, species must go extinct, and genes must mutate. All of these processes destroy information. Selection can turn energy into new information, but it cannot re-create the lost information.

    Cyclic processes, such as planetary orbits and rotations, are dramatically different; they lose energy very slowly, or not at all.

    (As a side issue, that is a terrible title for a book. It’s three fails rolled into one. First, nearly every climate scientist accepts that there are cyclic drivers of climate, such as the changes in the shape of the Earth’s orbit, and the tilt of the Earth’s axis (known collectively as Mikhailovanitch cycles). Acyclic drivers, such as human emissions of CO2 are also accepted by nearly all climate scientists. “Real or Imaginary” is a false dichotomy. Second, weather is not climate. Third, essentially all meteorologists accept there are both cyclic (such as ENSO and AO) weather phenomena and acyclic weather phenomena. On the other hand, we’re all too aware of good books with bad titles, so it’s not a comment on the quality of the book.)

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  17. 17. Jerzy New 4:59 am 04/10/2012

    This must be true – for example trolls come in circles, again and again :)

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  18. 18. Jerzy New 5:07 am 04/10/2012

    Mobile hindlimbs of Psittacosaurus are intriguing anyway. Some rock-climbing behaviour? Adaptation to hiding in burrows?

    Amphibious reconstruction requires radically different view of animal’s feet from how ceratopsian feet are usually reconstructed. I guess it would be pretty easy to disprove/prove conslusively.

    Re: new Ceratopsian genera. I see that paleontologists view different arrangement of horns as sufficent to name a new genus, resulting in many small genera similar in postcranial skeleton. Much like bovids and proboscideans are sometimes considered oversplit.

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  19. 19. Andreas Johansson 6:19 am 04/10/2012

    David Marjanović

    First, ceratopsians aren’t lizards. Just… look at their skeletons. It’s completely obvious that they’re not lizards.

    What’s completely obvious to a zoologist frequently isn’t to a layman. I don’t know anything about VDog’s level of background knowledge, but lots of laymen have very vague ideas of what lizards are like.

    (I once suggested, as an example of an “obvious” difference between lizards and sauropods, that the former have sprawling legs and the later vertical ones. It fell flat because my interlocutor had never reflected on what direction a lizard’s legs may point.)

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  20. 20. Heteromeles 11:49 am 04/10/2012

    Still, if evolution is cyclical, we’re all either recycling as bacteria, Ichthyostegians, dinosaurs, or at least therapsids.

    Even though I think there’s something reptilian about those currently in power (e.g. lawyers and financiers), I don’t think that’s evidence that we’re cyclically re-evolving as dinosaurs right now…

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  21. 21. llewelly 2:21 pm 04/10/2012

    Heteromeles, you know there are well over 10,000 species of dinosaurs alive today …

    Perhaps they’re not content with the air, and are plotting a cyclic reconquering of the land, which was the domain of their Mesozoic ancestors …

    Evolution, after all, works through extinction.

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  22. 22. naishd 2:42 pm 04/10/2012

    Jerzy says (comment 18)…

    ——————
    Re: new Ceratopsian genera. I see that paleontologists view different arrangement of horns as sufficent to name a new genus, resulting in many small genera similar in postcranial skeleton. Much like bovids and proboscideans are sometimes considered oversplit.
    ——————

    This is only partly accurate – the taxa you have in mind do differ in horn arrangement, but they’re also different in numerous other ways. And, as we’ve said before in connection with ceratopsians and hadrosaurs, the idea that these animals are all alike postcranially is a myth, perpetuated by the fact that postcrania are all alike because everyone “knows” they are, and destroyed every time anyone actually describes and compares postcranial elements in detail (e.g., Brett-Surman & Wagner 2007, Mallon & Holmes 2010).

    Having said all that, the thorny issue of whether horned dinosaur (and other dinosaur) ‘genera’ are ‘oversplit’ or ‘overlumped’ is pretty much subjective – I covered it in reasonable detail in the review of Greg Paul’s Dinosaurs: A Field Guide. As I said then, never forget that ‘genera’ are human constructs, not necessarily ‘obvious’ natural units. Do we lump all centrosaurines in a super-inclusive Centrosaurus, or do we stick with tradition and recognise Styracosaurus, Einiosaurus, Achelousaurus, Pachyrhinosaurus and so on? We’ve been doing the latter for so long, it doesn’t make much sense to confuse everyone by giving up on it and doing something different.

    Darren

    Refs – -

    Brett-Surman, M. K. & Wagner, J. R. 2007. Discussion of character analysis of the appendicular anatomy in Campanian and Maastrichtian North American hadrosaurids – variation and ontogeny. In Carpenter, K. (ed) Horns and Beaks: Ceratopsian and Ornithopod Dinosaurs. Indiana University Press (Bloomington & Indianapolis), pp. 135-169.

    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, pp. 189-202.

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  23. 23. naishd 2:47 pm 04/10/2012

    I only just discovered that the word ‘Perspectives’ had been spelt ‘Pespectives’ throughout the whole of the above article. What a dumbass – good job nobody noticed (right?).

    Darren

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  24. 24. VDog3EK0!uNz 4:45 pm 04/10/2012

    I appreciate you all have been considerate enough to discuss such an unusual conjecture. I acknowledge my ignorance of zoology. However, from the viewpoint of the history of natural philosophy, I think you are all still very much under the influence of Etienne Tempier, bishop of Paris. In 1277 CE he issued a list of condemnations meant to bring under control Aristotelian influence. Proposition #92 condemned belief in cyclical concepts of history and had a strong influence tending to make belief in such concepts taboo in Western Europe. To judge from your overall negative reception I suggest you are (as most Westerners still are) under Tempier’s (and Augustine’s) influence. However, the science of geology is much more open to and accepting of cyclical concepts because there is so much evidence of cycles in geology.

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  25. 25. VDog3EK0!uNz 4:48 pm 04/10/2012

    Planets, Stars, and Orbs: The Medieval Cosmos, 1200-1687 by Edward Grant c.1994

    Science and creation : from eternal cycles to an oscillating universe
    by Stanley Jaki historian of astronomy
    c.1986

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  26. 26. VDog3EK0!uNz 5:37 pm 04/10/2012

    Heteromeles: “Do you begin to see how ridiculous the whole idea of circular evolution is?”

    I think what is ridiculous is the use of the straw man method of argument you have employed. Nothing was said of any kind of Nietzschean absolute ultimate cycles but only of cyclical influence or factors due to climate.

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  27. 27. VDog3EK0!uNz 5:44 pm 04/10/2012

    llewelly:”But the most serious flaw in the notion of cyclic evolution is the fact that evolution is inherently destructive”

    There is something called convergent evolution, and the typical confounding of extinction and extirpation in most discussions tends to exaggerate the amount of extinction really taking place. Perhaps evolution has not necessarily been quite as destructive as currently supposed.

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  28. 28. VDog3EK0!uNz 5:55 pm 04/10/2012

    llewelly

    Really, the mutations and variations are so abundant that it seems evolution is mainly creative.

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  29. 29. BilBy 6:00 pm 04/10/2012

    PLEASE can we have a ‘recent comments’ button?

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  30. 30. Halbred 6:18 pm 04/10/2012

    Convergent evolution is great, but it doesn’t negate extinction rates or events. Dolphins look superficially ichthyosaur-like, but do note that all the ichthyosaurs are now EXTINCT, and dolphins are NOT ichythosaurs. And, when you really start looking at the two, dolphins aren’t all that similar to ichthyosaurs aside from gross outline.

    Let’s take the ceratopsid example: in the Permian, there were wierd critters called dinocephalians (like Estemmenosuchus) who have wierd horns and thickened domes. But they lived completely different lives. And it wasn’t the climate that led to the evolution of horns and bosses and spikes, it was sexual selection (in both groups).

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  31. 31. Heteromeles 7:27 pm 04/10/2012

    Sorry VDog3EK0!uNz, that was only a straw man to someone who doesn’t understand convergent evolution.

    Convergent evolution doesn’t work in circles. Rather, it’s works through things like aerodynamics and hydrodynamics. To pick one example, aquatic plants tend to look similar because there are a few good ways to deal with the problems posed by living in water (streamlining, limited gas for photosynthesis). Similarly, trees have evolved multiple times, because an arborescent growth form is a good way to compete for light in a crowded environment. There’s nothing circular about it, and if you read something like Carlquist’s Island Biology you’ll find out that tree-like forms evolve, not in some sort of circular history, but all the time. On islands.

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  32. 32. Margaret Pye 9:56 pm 04/10/2012

    Whether or not climate works in cycles (not my area), two geological periods with the same climate may evolve completely different life forms, depending on what life forms they started out with and on what chance mutations happened to occur.

    Now, I suspect that there’s /some/ degree of niche and lifestyle overlap between some modern hoofed mammals and the smaller ceratopsians, but a wild boar is clearly not the same thing as Protoceratops.

    Could a boar evolve a bony frill on its skull, for visual display or neck protection? Quite plausibly, although they haven’t yet. Are boars obliged to evolve frills because they are like ceratopsians and ceratopsians had frills? No – it would be just as easy for them to evolve other display/intraspecific combat features (a lot of pig species and extinct pig-like species have had striking display/combat features, but as far as I know no hoofed mammal has ever had a ceratopsian-style frill), or them to keep the same display/combat features or reduce the display/combat features and put the energy into something else (fast growth, fecundity…) instead.

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  33. 33. punchfish 11:32 pm 04/10/2012

    I have a phylogeny question (which feels like a derail even though it shouldn’t).

    The first cladogram nests Marginocephalia within Genasauria. Is that the consensus? I’m curious where people stand on the Heterodontosauriformes (Heterdontosauridae + Marginocephalia). It seemed like a big deal when Yinlong was first announced but I don’t hear much about it anymore …

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  34. 34. Jerzy New 4:22 am 04/11/2012

    @trolls
    You can say rhino is a very good modern version of ceratopsian dinosaur.

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  35. 35. Jerzy New 4:35 am 04/11/2012

    @naishd
    Genus is artifical concept, but oversplitting/lumping problem is real. The concept – whatever the definition – needs to be used consistently in a group like dinosaurs or mammals.

    In mammals, it was noted that large ungulates have many genera with one species and small mammals have speciose genera, so large mammals are likely oversplit and small mammals overlumped (another thing which I find surprisingly right but never had time to think more). The same seems true for ceratopsians.

    Of course, at the end, dinosaurs are likely overlumped in general – it is hard to find a dinosaur genus with 8 or 10 valid species.

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  36. 36. vdinets 12:35 pm 04/11/2012

    Jerzy: who says the number of large and small genera has to be the same in every taxon? Large mammals have better dispersal abilities and so are more likely to evolve into different lifestyles (which ultimately means different body plans, while small mammals are likely to have numerous allopatric species. There is only one pronghorn and one buffalo in North American grasslands, but lots of ground squirrels and pocket gophers.
    Of course, this argument doesn’t work for bats – and note that there is only one large genus of bats in North America.

    As for dinosaurs, I suspect that many congeneric species simply can’t be distinguished from fossils, especially if the fossils are not complete (which is almost always the case).

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  37. 37. David Marjanović 12:40 pm 04/11/2012

    evolution is inherently destructive; lineages must die, species must go extinct, and genes must mutate. All of these processes destroy information. Selection can turn energy into new information, but it cannot re-create the lost information.

    Mutation creates information. However, it is random; the probability that mutation recreates lost information is… limited.

    What’s completely obvious to a zoologist frequently isn’t to a layman. I don’t know anything about VDog’s level of background knowledge, but lots of laymen have very vague ideas of what lizards are like.

    True. I should have worded it as “compare the skeleton of a lizard to that of a ceratopsian, and the scales shall fall off your eyes”.

    There’s much more I’d like to address, but I have no time today.

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  38. 38. VDog3EK0!uNz 5:24 pm 04/11/2012

    “Mutation creates information. However, it is random; the probability that mutation recreates lost information is… limited.”

    This is again a straw man criticism assuming cyclical evolution would be some sort of exact repetition such as the Stoics insisted upon. A mutation would survive under similar conditions if it had similar traits.

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  39. 39. VDog3EK0!uNz 5:30 pm 04/11/2012

    “Convergent evolution doesn’t work in circles.”

    This is also straw man because again we are not talking about exact repetition. Convergent evolution repeatedly brings about similar forms, due to similar conditions. This could well be described as cyclical evolution to a degree, could it not?

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  40. 40. Heteromeles 5:32 pm 04/11/2012

    @VDog3EK0!uNz: so circular evolution is whatever you want it to be, so long as you win the argument? You’re throwing up more obvious straw men than we ever could, what with citing dead philosophers at us ignorant biologists, as if that disproved what we were saying.

    @Everyone else: getting back to ceratopsians, what do we know about their climatological tolerances? While I can amuse myself with the idea of “Crinitoceratops,” is there any evidence of species that dealt with snow or ice on a regular basis?

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  41. 41. VDog3EK0!uNz 5:34 pm 04/11/2012

    “Whether or not climate works in cycles (not my area), two geological periods with the same climate may evolve completely different life forms, depending on what life forms they started out with and on what chance mutations happened to occur.”
    Yes! This is why cyclical components of evolution would not result in exactly identical repetition.

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  42. 42. VDog3EK0!uNz 5:38 pm 04/11/2012

    Why hasn’t anyone mentioned Dollo’s Law?

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  43. 43. VDog3EK0!uNz 6:12 pm 04/11/2012

    Dollo’s Law of Irreversibility (also known as Dollo’s Law and Dollo’s Principle) is a hypothesis proposed by French-born Belgian paleontologist Louis Dollo (1857-1931) in 1890 that states that evolution is not reversible. This hypothesis was first stated by Dollo in this way: “An organism is unable to return, even partially, to a previous stage already realized in the ranks of its ancestors.”. According to this hypothesis a structure or organ that has been lost or discarded through the process of evolution will not reappear in exactly the same form in that line of organisms.

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  44. 44. VDog3EK0!uNz 6:13 pm 04/11/2012

    -Wikipedia

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  45. 45. Halbred 6:52 pm 04/11/2012

    Heteromeles wrote: “@Everyone else: getting back to ceratopsians, what do we know about their climatological tolerances? While I can amuse myself with the idea of “Crinitoceratops,” is there any evidence of species that dealt with snow or ice on a regular basis?”

    Sure! Alaska’s Pachyrhinosaurus perotorum (in press) dealt with freezing temperatures, snow, and long periods of darkness on the North Slope (which was actually farther north than it is today). Erickson & Drunkmiller (2011), using histology, demonstrated that our pachyrhinosaurus probably did not migrate or hibernate, but stayed active throughout the year. They grew to sexual maturity by nine years and died around nineteen or twenty.

    Our other dinosaurs, including Albertosaurus, Dromaeosaurus, Troodon, and Edmontosaurus went through the same stresses.

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  46. 46. Schenck 9:04 am 04/13/2012

    Just a question, as far as pedigrees. I see a few connections to Darwin’s Bulldog through Osborn, I hadn’t heard he was his student. Checking on wikipedia, they have Osborn as having worked with Huxley, but not as his graduate student. They don’t list Osborn’s Sci.D advisor (also seems to be a connection to Cope as an undergrad).

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  47. 47. Bruce Mohn 9:31 am 04/13/2012

    The various suggestions that fibers or quills associated with the tails and spines of dinosaurs are indications that those species were amphibious ignores the general adaptations to amphibious or aquatic life. All such animals, be they mammals, birds, reptiles or amphibians have a reduction in the lengths of their femora and tibiae/fibulae and an increase in the length and or number of the bones in their pes. These adaptations aren’t seen in dinosaurs. It seems likely that if these structures were collagenous fibers supporting a frill, then they served a display role. That said, all of the evidence points to the fibers or quills being external independent structures ie feathers or quills.

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  48. 48. Heteromeles 6:49 pm 04/13/2012

    @Halbred: Thanks! (head slap: I’d forgotten that Nova did an episode on those dinosaurs last season).

    Are there any skeletal correlates (proportions, reduced frill and horn sizes, bigger eyes) that go with living near the poles? As I recall, Pachyrhinosaurus perotorum had that weird nasal boss in place of a horn. Probably too much to speculate whether that’s a climate adaptation in the genus, but it does make me curious.

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  49. 49. Halbred 7:39 pm 04/13/2012

    It was easy to forget about that NOVA episode.

    The expansive nasal boss is actually a pachyrhinosaurine apomorphy: Montana’s Achelousaurus has one you might call an “incipiant” boss, but all three species of Pachyrhinosaurus (P. canadensis, P. lakustai, P. perotorum), as well as a potential fourth species described in this volume, have big bosses as adults. Juveniles start out with narrow nasal horns, but the horn grows laterally and the top starts to honeycomb and the interior starts to reabsorb. It’s a wierd process.

    P. perotorum isn’t much different, morphologically speaking, from either of the southern species. Like its description says, it’s really just features of the parietal, its age, and its location that differentiate it (so far–only the holotype skull and paratype parietal fragments have been described). What IS interesting is that Pachyrhinosaurus seems to be the last surviving centrosaurine, and then only in Alaska. I could be wrong on this–anyone know of any bitter-end-of-the-Cretaceous centrosaurines I’m forgetting?

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  50. 50. David Marjanović 9:04 am 04/14/2012

    so circular evolution is whatever you want it to be, so long as you win the argument?

    Exactly. How much convergence counts as cyclical, and how little is too little?

    Why hasn’t anyone mentioned Dollo’s Law?

    Because it’s not 1915 anymore? Dollo’s “law” isn’t a law of physics (even though Dollo may have thought otherwise); it’s just a statement about probability.

    Erickson & Drunkmiller

    Druckenmiller.

    also seems to be a connection to Cope as an undergrad

    Ah.

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  51. 51. LPanzarin 11:26 am 04/19/2012

    Wow! Thanks Darren for the kind words, I really appreciated (although I have to disagree…there is still a lot to learn!)
    Cheers,
    Lukas

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  52. 52. John Conway 11:59 am 04/27/2012

    A Gentleman Scholar (VDog3EK0!uNz) wrote:

    I think you are all still very much under the influence of Etienne Tempier, bishop of Paris. In 1277 CE [...]

    That’s some (as the kids say) epic lulz right there. Where do you get these, ahem, amusing people?

    Link to this

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