EDITORIAL

THE ANATOMICAL RECORD 297:341–343 (2014)

VVC 2014 WILEY PERIODICALS, INC.

What’s So Special About Squamates?

The study of the morphological structure of squa-mates (lizards and snakes) has been a popular subjectamong doctors, morphologists, herpetologists, andpaleontologists for more than three centuries. Some ofthe earliest known technical studies of these organ-isms focused on vipers and the medical aspects associ-ated with envenomation (e.g., Charas, 1669; Tyson,1683). In fact, most early works on reptile biologywere medically oriented and written by physicians.But today, scientists with diverse backgrounds andresearch interests study these organisms. Currentsquamate research encompasses evolutionary history,climate change, and space materials, to mention a few.

Squamate morphology is studied primarily by her-petologists and paleontologists. Yet despite the over-lapping interests of these two groups and the largeamount of morphological literature produced inrecent years, it is uncommon to find members ofthese communities working side by side. Herpetolo-gists and paleontologists tend to publish in differentspecialized journals and attend separate scientificmeetings. Many of them are, regrettably, not evenaware of the work of members of the other commu-nity! (although this varies and depends on eachresearcher’s bibliographic “appetite”). A clear exam-ple of this lack of collaboration between herpetolo-gists and paleontologists is the Deep Scaly project,which was the largest study on squamate evolutionever undertaken (http://archive.fieldmuseum.org/deepscaly/). This project originally included both her-petologists and paleontologists as co-funded collabora-tors, but the two teams diverged and publishedindependently, and each group developed a differentphylogeny based on their own independent analysesof a data set that was composed of the largest datapartitions for squamate reptiles ever produced(Gauthier et al., 2012; Wiens et al., 2012).

Last year, James D. Gardner (Curator of Palaeoher-petology at the Royal Tyrrell Museum of Palaeontologyin Alberta Canada) organized a symposium at the 7thWorld Congress of Herpetology entitled “Insights fromthe Fossil Record” (see, Pearson and Jones, 2013 foran overview of the meeting). One of the major achieve-ments from the two-day symposium was bringing pale-ontologists and herpetologists together. The majorityof presenters at the symposium were paleontologists,and they sent a clear message to the herpetologist-dominated audience: the study of paleoherpetology hasnot stopped producing awesome discoveries that helpus to better understand the biology of today’s livingforms. Likewise, many paleontologists at the meetingwere attending talks and posters by herpetologists to

find new sources of information that could apply totheir own research projects.

During that meeting I came across one poster thatexemplified the interdisciplinary integration betweenpaleontology and herpetology. The authors simulatedthe mechanics of mosasaur swimming using prostheticmosasaur-like tails attached to the semiaquatic monitorVaranus salvator (Young, 2013; see also Lindgren et al,.2011). Despite your opinion on the appropriateness oftaxon selection for this study (mosasaurs are eitherpart of the Scleroglossan stem or part of the crown Var-anoidea clade), the whole idea was very creative.

James D. Gardner wanted to put together a volumein which the attendants of that meeting could presenttheir research in more detail. That initiative was par-tially unsuccessful1, but I decided to borrow his ideaand I took on the challenge of combining herpetologyand paleontology in a single volume, in which squamatemorphology is operating as the interdisciplinary linguafranca. This task was not easy but, luckily for me, asthe guest editor and the person responsible for gettingpeople involved, I received positive responses from anumber of experts working on squamate morphology.

In recruiting contributions for this volume, I focusedon studies by specialists working on the major clades ofthe squamate tree of life, and gladly, I received manyinteresting contributions. The volume starts with Dr.Christopher J. Bell and Jim I. Mead’s appreciation ofthe status quo of skeletal collections in museums. Theyargue that the anatomical research program is still adynamic discipline and not an expired field of studyfrom the Victorian era that is slowly marching towardits end. Original research papers in this volume com-prise the anatomy of Iguania (the chameleon’s atlanto-axial complex, pedal grasping capabilities, and pectoralgirdle anatomy), Gekkota (a comprehensive fossil recordcatalog, cranial joints), Lacertoidea (hemipeneal mor-phology, brille formation, cranial joints), Scincoidea(a miniaturized and putative fossil form from thePyrenees), Amphisbaenia (ancestral morphologyand niche modeling of rhineurids), Anguimorpha (a newshinisaurid record for North America, the lower jawand tooth structure of the some anguids), and Serpentes(fossil record, jaw musculature, and gut morphology).

1In addition to the Anatomical Record special issue, JamesD. Gardner and Randall L. Nydam edited anothermulti-authored volume entitled: Mesozoic and Cenozoiclissamphibian and squamate assemblages of Laurasia. Palaeo-biodiversity and Palaeoenvironments, 93(4), Special Issue.

Returning to the question formulated in the title:what’s so special about squamates? More than one hun-dred years has passed since the current perception ofthe group was formed (e.g., Cope, 1864; Boulenger,1884). Ninety years ago, Camp (1923), in his character-based classification of lizards, produced the foundationsfor future research. In his monograph, he organized liz-ards and proposed methods to delimitate monophyleticgroups long before the revolutionary works of Willi Hen-nig (See Moody, 1985). Following this early classifica-tion, several authors have produced improvements tothe classification of squamates based on morphology(e.g., McDowell and Bogert, 1954; Underwood, 1954,1967; Kluge, 1967, 1989; Rieppel, 1979, 1980, 1984;Borsuk-Białynicka, 1983; Presch, 1983; Evans, 1984;Gauthier, 1984; Benton, 1985; Estes et al., 1988; Frostand Etheridge, 1989; Lee, 1997; Caldwell, 1999; Conrad,2008; Gauthier et al., 2012). These studies, along withmany more not mentioned, have provided a road mapthat has facilitated further advances in squamateresearch and promoted its applications in other fields.

Squamata originated in the Early Jurassic, around193 Mya (Jones et al., 2013). Today this group accountsfor the majority of living reptiles and includes morethan 9,200 species. In terms of diversity, that number isnearly comparable with birds (approximately 10,000species), and surpasses the number of mammals (5,702species) and amphibians (7,177 species). Members ofSquamata are important components of the world’s eco-systems. They are distributed on all the continentsexcept Antarctica, are found up to high latitudes in bothNorthern and Southern Hemispheres, and are distrib-uted in a variety of habitats from tropical forests, to bar-ren territories such as deserts and cold regions. Sadly,they are also disappearing fast as global temperatureschange and anthropomorphic impacts on their naturalterritories become more severe (Sinervo et al., 2010, seealso Clusella-Trullas and Chown, 2011).

In a time when the future of squamates doesn’t lookgreat, the minimum we can do is appreciate squa-mates for their evolutionary success and recognizetheir struggle for survival against the threats causedby our own civilization. I am optimistic that interdisci-plinary volumes like this one will help to demolish theintellectual wall between herpetologists and paleontol-ogists and will contribute to our understanding andconservation of these amazing organisms.

Finally, I want to mention that this special volumewouldn’t be in your hands (or glowing on your com-puter screen) without the tremendous help from ScottMiller, Kurt Albertine, and Rosalie McFarlane. I amalso grateful to the paleoartist Stephanie Abramowiczwho brought back to life the extinct gecko Hoburo-gecko suchanovi from H€o€ovor, Mongolia that isdepicted on the cover of this issue. Although my selec-tion of this squamate for the cover was biased by myown interests, gekkotans represent squamates wellbecause they are consistently recovered as one of themost basal squamate groups in both molecular andmorphological data sets, and they historically havebeen allied with virtually all other squamate clades.

I also cannot forget to thank Dr. Aaron M. Bauerand Villanova University for their support during theproduction of this volume. Finally, I want to acknowl-edge the effort of all the people that contributed tothis volume by spending hours editing these manu-scripts. In alphabetical order:

Aaron M. Bauer, Villanova University, USAFaysal Bibi, American Museum of Natural History,

USAArnau Bolet, Institut Catal�a de Paleontologia

Miquel Crusafont, SpainAndrej �Cer�nansk�y, Senckenberg Research Institute,

Germany/Geological Institute, Slovak Academy ofSciences, Slovakia

Jack L. Conrad, New York College of OsteopathicMedicine/American Museum of Natural History,USA

Ammon Corl, University of California at SantaCruz, USA

David Cundall, Lehigh University, USARui Diogo, Howard University/The George

Washington University, USAAnnelise Folie, Royal Belgian Institute of Natural

Sciences, BelgiumKathleen Foster, University of California at

Riverside, USAElyse S. Freitas, Villanova University, USAAnthony Herrel, CNRS/Mus�eum national d’Histoire

naturelle, FranceCasey Holliday, University of Missouri, USAKenneth Kardong, Washington State University, USAJozef Klembara, Comenius University in Bratislava,

SlovakiaNicholas Longrich, Yale University, USAJonathan Losos, Museum of Comparative Zoology/

Harvard University, USACarlo Meloro, Universit�a degli Studi di NapoliFederico II, Italy/The University of Hull, UKRicardo (Ueso) Montero, Instituto de Herpetolog�ıa/

Fundaci�on Miguel Lillo, ArgentinaScott Miller, The Anatomical Record/University of

Utah, USAKevin Neal, Villanova University, USARandal Nydam, Midwestern University, USASamantha Payne, University of Toronto, CanadaAna L�ucia Prudente, Museu Paraense Em�ılio

Goeldi, BrazilJean-Claude Rage, CR2P, UMR 7207 CNRS/Mus�eum

national d’Histoire naturelle, FranceBeate R€oll, University of Veterinary Medicine

Hannover, GermanySantiago J. S�anchez-Pacheco, University of Toronto,

CanadaKathleen K. Smith, Duke University, USAKrister Smith, Senckenberg Research Institute

Frankfurt/Main and Messel Research Station,Germany

Matthew Vickaryous, University of Guelph, Canada

342 EDITORIAL

Juan D. Daza*

Guest editorThe Anatomical Record

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*Correspondence to: Juan D. Daza, Biology Department,Villanova University, 800 Lancaster Avenue, Villanova PA19085. E-mail: juand.daza@gmail.com.

Present address: Department of Biological Sciences, SamHouston State University, 1900 Avenue I, Huntsville TX77341-2116, USA

Received 3 January 2014; Accepted: 3 January 2014.

DOI 10.1002/ar.22870Published online 31 January 2014 in Wiley Online Library(wileyonlinelibrary. com).

EDITORIAL 343