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Department of Zoology



I received my BSc in biology from the University of Michigan in 1995, and my PhD in geology (with a concentration in vertebrate paleontology) from Southern Methodist University in 2002. I held a National Science Foundation Postdoctoral Fellowship in Biological Informatics at the Smithsonian Institution and Queen Mary, University of London from 2002-2005, and was faculty at the George Washington University, University of Toronto, and University of Nebraska-Lincoln prior to joining the Department of Zoology in 2015.

Museum- and field studies are fundamental components of my research and teaching. I have 30 years of natural history museum experience ranging from specimen preparation and conservation, database development, public education and outreach, and curation. My field research has covered the Mesozoic and Cenozoic of Africa, the Americas, and South Asia. My current focus is on the tropics, with projects spanning the Palaeocene through Holocene in Colombia, Kenya, Ethiopia, and Indonesia.


I am a broadly-trained vertebrate paleontologist and my research interests align along two axes, one primarily ecological and one primarily evolutionary developmental: 1) the evolution of modern tropical vertebrate clades, focusing on the relationship between fauna and environment during the Paleogene and Neogene; and 2) the evolution of vertebrate body forms and inferring the roles of regulatory genetic networks and novel developmental mechanisms from anatomy of extant and fossil taxa. Although the questions I address and the methods I employ are not taxon-specific, my focus is on reptiles because they are diverse, important components of modern ecosystems, possess a dense fossil record during the last 66 million years, and exhibit extraordinary plasticity in body form and ecophenotype, including axial elongation, limblessness, and the evolution of shells. My work integrates phenomic data, as quantified and qualified skeletal anatomy derived from field and museum studies, with molecular, environmental, and paleoclimate datasets. 

The newest component of my research is the integration of ecometric trait data from fossil vertebrates with modern records to help forecast biotic responses to anthropogenic climate change as a component of taxon-free conservation paleobiology. In this work, I collaborate with colleagues from Kenya, Ethiopia, Germany, Finland, France, and the United States.


Key publications: 

Parker, A. K., J. Müller, J-R Boisserie, and J. J. Head. 2023. The utility of body size as a functional trait to link the past and present in a diverse reptile clade. Proceedings of the National Academy of Sciences, U.S.A. 120(71).

Lauer, D. A., A. M. Lawing, R. A. Short, F.K. Manthi, J. Müller, J.J. Head, and J. L. McGuire. 2023. Disruption of trait-environment relationships in African megafauna occurred in the middle Pleistocene. Nature Communications, 14:4016.

Head, J. J., A. F. C. Howard, and J. Müller. 2022. The first 80 million years of snake evolution: The Mesozoic fossil record of snakes and its implications for origin hypotheses, biogeography, and mass extinction. Pps. 26-55 In D. Gower & H. Zaher (eds.). The Origin and Early Evolutionary History of Snakes. Cambridge University Press.

Jameson, T. J. M., J. W. Streicher, L. Manuelli, J. J. Head, and E. N. Smith. 2022. Miniaturization in direct-developing frogs from Mexico with the description of six new species. Herpetological Monographs, 36(1):1-48.

Criswell, K.E., L. E. Roberts, E. T. Koo, J. J. Head, and J. A. Gillis. 2021. hox gene expression predicts tetrapod-like axial regionalization in the skate, Leucoraja erinacea. Proceedings of the National Academy of Sciences, U.S.A. 118(51).

Head, J. J. 2021. A South American snake lineage from the Eocene Greenhouse of North America and a reappraisal of the fossil record of “anilioid” snakes. Geobios.

Head, J. J., K. de Queiroz, and H. W. Greene. 2020. Pan-Serpentes. Pp. 1093-1096 In: K. de Queiroz, P. D. Cantino and J. A. Gauthier (eds.), Phylonyms: A Companion to the PhyloCode. Berkeley: CRC Press. 

Head, J. J., K. de Queiroz, and H. W. Greene. 2020. Serpentes. Pp. 1097-1105 In: K. de Queiroz, P. D. Cantino and J. A. Gauthier (eds.), Phylonyms: A Companion to the PhyloCode. Berkeley: CRC Press.

Whiting, E.T. and Head, J.J. 2020. Neogene crocodylians from the Central Great Plains: spatiotemporal histories and relationships with regional climatic and environmental changes. Journal of Vertebrate Paleontology, p.e1764007.

Head, J. J., and J. Müller. 2020. Squamate reptiles from Kanapoi: Faunal evidence for hominin paleoenvironments. Journal of Human Evolution. 140, 102451.

Westphal, N., K. Mahlow, J. J. Head, and J. Müller. 2019. Pectoral myology of limb-reduced worm lizards (Squamata, Amphisbaenia) suggests decoupling of the musculoskeletal system during the evolution of body elongation. BMC evolutionary biology, 19(1).

Jones, K. E., K. D. Angielczyk, P. D. Polly, J. J. Head, V. Fernandez, J.K., Lungmus, S. Tulga, and S.E. Pierce. 2018. Fossils reveal the complex evolutionary history of the mammalian regionalized spine. Science. doi: 10.1126/science.aar3126.

Vermillion, W. A., P. D. Polly, J. J. Head, J. T. Eronen, and A. M. Lawing. 2018. Ecometrics: A trait-based approach to paleoclimate and paleoenvironmental reconstruction. Pp. 373-394. InCroft, D.A., S.W. Simpson, and D.F. Su (eds.), Methods in Paleoecology: Reconstructing Cenozoic Terrestrial Environments and Ecological Communities. Springer, Dordrecht.

Barnosky, A. D., E. A. Hadly, P. Gonzalez, J. J. Head, P. D. Polly, A. M. Lawing, J. T. Eronen, D. D. Ackerly, K. Alex, E. Biber, J. Blois, J. Brashares, G. Ceballos, E. Davis, G. P. Dietl, R. Dirzo, H. Doremus, M. Fortelius, H. W. Greene, J. Hellmann, T. Hickler, S. T. Jackson, M. Kemp, P. L. Koch, C. Kremen, E. L. Lindsey, C. Looy, C. R. Marshall, C. Mendenhall, A.S Mulch, A. M. Mychajliw, C. Nowak, U. Ramakrishnan, J. Schnitzler, K. D. Shrestha, K. Solari, L. Stegner, M. A. Stegner, N. Chr. Stenseth, M. H. Wake. Z. Zhang. 2017. Merging paleobiology with conservation biology to guide the future of terrestrial ecosystems. Science, 355 (6325). doi: 10.1126/science.aah4787

Head, J. J., and P. D. Polly. 2015. Evolution of the snake body form reveals homoplasy in amniote Hox gene function. Nature, 520:86-89. doi: 10.1038/nature14042.

P. D. Polly, and J. J. Head. 2015. Measuring Earth-Life Transitions: Ecometric analysis of functional traits from Late Cenozoic Vertebrates. The Paleontological Society Papers, 21: 21-46.

Head, J. J., G. F. Gunnell, P. A. Holroyd, J. H. Hutchison, and R. L. Ciochon. 2013. Giant lizards occupied herbivorous mammalian ecospace during the Paleogene greenhouse in Southeast Asia. Proceedings of the Royal Society of London, Series B. doi:10.1098/rspb.2013.0665.

Lawing, A. M., J. J. Head, and P. D. Polly. 2012. The ecology of morphology: the ecometrics of locomotion and macroenvironment in North American snakes. Pp. 117-146 in J. Louys (ed), Palaeontology in Ecology and Conservation. Springer, New York.

Müller, J., C. Hipsley, J. J. Head, N. Kardjilov, A. Hilger, M. Wuttke, and R. R. Reisz. 2011. Limbed lizard from the Eocene of Germany reveals amphisbaenian origins. Nature, 473, 364–367.

Parham, J. F, P. C. J. Donoghue, C. J. Bell, T. D. Calway, J. J. Head, P. A. Holroyd, J. G. Inoue, R. B. Irmis, W. G. Joyce, D. T. Ksepka, J. S. L. Patańe, N. D. Smith, J. E. Tarver, M. van Tuinen, Z. Yang, K. D. Angielczyk, J. Greenwood, C. A. Hipsley, L. L. Jacobs, P. J. Makovicky, J. Müller, K. T. Smith, J. M. Theodor, R. C. M. Warnock, M. J. Benton. 2012. Best practices for applying paleontological data to molecular divergence dating analyses. Systematic Biology, 61 (2): 346-359.

Müller, J., T. Scheyer, J. J. Head, P.M. Barrett, P. Ericson, D. Pol, and M. R. Sanchéz-Villagra. 2010. The evolution of vertebral numbers in recent and fossil amniotes: The roles of homeotic effects and somitogenesis. Proceedings of the National Academy of Sciences of the United States of America (PNAS), 107:2118-2123

Ksepka, D. T., M. J. Benton, M. T. Carrano, M. A. Gandolfo, J. J. Head, E. J. Hermsen, W. G. Joyce, K. S. Lamm, J. S. L. Patané, M. J. Phillips, P. D. Polly, J. L. Ware, R. C. M. Warnock, M. van Tuinen, J. F. Parham. 2011. Synthesizing and databasing fossil calibrations: divergence dating and beyond. Biology Letters, doi: 10.1098/rsbl.2011.0356. 

Wilson, J. A., D. Mohabey, S. Peters, and J. J. Head. 2010. Predation upon hatchling sauropod dinosaurs by a new basal snake from the Late Cretaceous of India. PLOS Biology. 8:1–5 doi:10.1371/journal.pbio.1000322.g005.

Head, J. J., J. I. Bloch, A. K. Hastings, J. R. Bourque, E. A. Cadena, F. A. Herrera, P. D. Polly, and C. A. Jaramillo. 2009. Giant boid snake from the Paleocene neotropics reveals hotter past equatorial temperatures. Nature, 457:715-717. 

Head, J. J., P. M. Barrett, and E. J. Rayfield. 2009. Neurocranial osteology and systematic relationships of Varanus (Megalania) prisca Owen (Squamata, Varanidae). Zoological Journal of the Linnaean Society of London, 155:445-457.

Reisz, R. R., and J. J. Head. 2008. Turtle origins out to sea. Nature, 456:450-451. 

Other publications: 

Head, J. J., and J. Müller. 2022. Late Miocene amphibians and squamates from the United Arab Emirates: Dispersal timing and paleoenvironments in the Arabian Peninsula. Pp. 111-123 In F. Bibi, B. Kraatz, M. Beech, and A. Hill (eds.), Sands of Time: Late Miocene Fossils from the Baynunah Formation, U.A.E.Springer, Cham, Switzerland.

Zonneveld J.-P., Z. E. E. Zonneveld, W. S. Bartels, M. K. Gingras, and J. J. Head. 2022. Bone modification features resulting from barnacle attachment on the bones of loggerhead sea turtles (Caretta caretta), Cumberland Island, Georgia, USA: Implications for the paleoecological, and taphonomic analyses of fossil sea turtles. Palaois, 37:650-670

Hood, A. S. C., M. D. Pashevich, A. D. Davento, A. A. A. Aryawan, C. A. Dahlsjö, J.-P. Caliman, M. Naim, J. J. Head, and E. C. Turner. 2020. Termite mounds house a diversity of taxa in oil palm plantations irrespective of understory management. Biotropica. doi: 10.1111/btp.12754

DeMar, D., J. Conrad, J. J. Head, D. Varricchio, and G. Wilson. 2017. A new Late Cretaceous iguanomorph from North America and the origin of New World Pleurodonta (Squamata, Iguania). Proceedings of the Royal Society B, 284: 20161902. doi: 10.1098/rspb.2016.1902.

Head, J. J., K. Mahlow, and J. Müller. 2016. Fossil calibration dates for molecular phylogenetic analysis of snakes 2: Caenophidia, Colubroidea, Elapoidea, Colubridae. Palaeontologia Electronica, 19.2.2FC: 1-21.

Moreno-Bernal, J., J. J. Head, and C. Jaramillo. 2016. Fossil Crocodilians from the High Guajira Peninsula of Colombia: Neogene faunal change in northernmost South America. Journal of Vertebrate Paleontology, doi: 10.1080/02724634.2016.1110586.

Gunnell, G. F., A. J. Winkler, E. R. Miller, J. J. Head, A. N. El-Barkooky, M. A. Gawad, W. J. Sanders, and P. D. Gingerich. 2016. Small vertebrates from Khasm El-Raqaba, late Middle Miocene, Eastern Desert, Egypt. Historical Biology, 28:59-171.

Head, J. J. 2015. Fossil calibration dates for molecular phylogenetic analysis of snakes 1: Serpentes, Alethinophidia, Boidae, Pythonidae, Palaeontologia Electronica, 18(1):1-17.

Cuff, A., M. Randau, J. J. Head, S. Pierce, J. J. Hutchison, and A. Goswami. 2015. Big Cat, small cat: Reconstructing body size evolution in living and extinct Felidae. Journal of Evolutionary Biology, 28:1516-1525. doi: 10.1111/jeb.12671.

Barrett, P. M., D. C. Evans, and J. J. Head. 2014. A re-evaluation of purported hadrosaurid dinosaur specimens from the ‘middle’ Cretaceous of England. Pp. 96-107 in In D. Eberth and D. C. Evans (eds.) Hadrosaurs, Indiana University Press. 

Conard. J., M. T. Carrano, and J. J. Head. 2014. Unusual soft-tissue preservation of a Crocodile Lizard (Squamata, Shinisauria) from the Green River Formation (Eocene). The Anatomical Record, 297:545-559. doi: 10.1002/ar.22868.

Head, J. J., A. Rincon, C. Suarez, C. Montes, and C. Jaramillo. 2012. Evidence for American interchange during the earliest Neogene: Boa from the Miocene of Panama. Journal of Vertebrate Paleontology, 32:1328-1334.

Mohabey, D., J. J. Head, and J. A. Wilson. 2011. A new species of the snake genus Madtsoia from the Cretaceous of India and its paleobiogeographical implications. Journal of Vertebrate Paleontology, 33:588-595. 

Sanders, K. L., Mumpuni, A. Hamidy, J. J. Head, and D. J. Gower. 2010. Phylogeny and divergence times of filesnakes (Acrochordus): Inferences from morphology, fossils and three molecular loci. Molecular Phylogenetics and Evolution, 56:857-867. 

Bajpai, S, and J. J. Head. 2008. An early Eocene palaeopheid snake from Vastan Lignite Mine, Gujarat, India. Gondwana Geological Magazine, 22:85-90. 

Head, J. J., and C. J. Bell. 2008. Snakes from Lemudong'o, Kenya Rift Valley. In: L. Hlusko (ed.), Stratigraphy, Paleontology, and Paleoecology of the Lemudong'o Site, Kenya. Kirtlandia, 56:177-179. 

Ambrose, S. H., C. J. Bell, R. L. Bernor, J.-R. Boisserie, C. M. Darwent, D. Degusta, A. Deino, N. Garcia, Y. Haile-Selassie, J. J. Head, L. J. Hlusko, F. C. Howell, M. D. Kyule, F. K. Manthi, E. M. Mathu, C. M. Nyamai, M. Pickford, H. Saegusa, T. A. Stidham, and M. A. J. Williams. 2008. The Paleoecology and Paleogeographic Context of Lemudong’o Locality 1, a Late Miocene Terrestrial Fossil Site in Southern Kenya. Kirtlandia, 56:38-52. 


Professor of Vertebrate Evolution and Ecology
Curator of Vertebrate Palaeontology, Herpetology, and Ichthyology University Museum of Zoology
Chair, Cambridge Biotomography Centre

Contact Details

Museum Room G.20
+44 (0)1223 (7)65387
Accepting applications for PhD students.