Sunset at the Fayum Depression, Egypt (c) K.L. Allen

Research Interests:

  • Comparative primate anatomy and functional osteology 

  • Early anthropoid paleontology 

  • Phylogenetic comparative statistics 

  • Three-dimensional geometric morphometrics 

  • Volume and surface-based visualization techniques (microCT/surface scanning) 

Primary Research

My research uses micro-computer tomography (microCT) scans of living and fossil primates to visualize the shape of the endocast (the volume within the braincase) of these animals. This project examines the relationships between brain size, brain shape, and brain proportions in primates and evaluates the evolution of these features in anthropoid (monkey, ape, and human) primates. In particular, I am interested in 1) the degree to which differences in endocast shape may reflect differences in brain proportions, and 2) the covariation of endocast shape and/or brain proportions with the overall organization of the skull. I aim to take a historical and evolutionary approach by using phylogenetic comparative methods and incorporating fossil primate specimens in my analysis, to determine the order of acquisition of these traits and their distribution through time.

Overarching Anthropological Research Questions

  • What are the ecological pressures shaping encephalization (brain size relative to body size) within and among mammalian clades? 

  • What are the spatial and evolutionary constraints acting on the evolution of the cranium? 

  • To what extent are osteology markers predictive of ecological behaviors? (Implications for reconstructing behavior in the fossil record) 

Additional Projects

  • Evaluating the relationship between ecological factors and encephalization in anthropoid evolution (diet quality in platyrrhines: Allen and Kay, 2012)

  • Comparison of upper and lower molar shear measures for diet reconstruction (Allen et al, IN PRESS) 

  • Estimation of brain proportions using virtual endocast “dissection” (mentoring of Duke undergraduate, manuscript in prep.)

  • Analysis of subfossil primate endocasts from Madagascar (data analysis phase) 

  • Analysis of intra- and interspecific variation in dental dimensions and surface topography among baboon populations in hybridization zones (collaboration with Jane Phillips-Conroy)

  • Reconstructing body size and encephalization from external cranial dimensions in primates

Recent Publications:

  • Sansalone G, Profico A, Wroe S, Allen K, Ledogar J, Ledogar S, Mitchell R, Mondanaro A, Melchionna M, Castiglione S, Serio C, Raia P. (2023) Homo sapiens and Neanderthals share high cerebral cortex integration into adulthood. Nature Ecology & Evolution. 7: 42–50. doi.org/10.1038/s41559-022-01933-6

  • Lynch LM, Allen KL. (2022) Relative brain volume of carnivorans has evolved in correlation with environmental and dietary variables differentially among clades. Brain, Behavior and Evolution. 97(5):284-297. doi: 10.1159/000523787

  • Van Handel AC, Lynch LM, Daruwalla JH, Higgins JP, Allen KL, Pet MA. (2021) Medial femoral trochlea flap reconstruction versus proximal row carpectomy for Kienböck’s Disease: A morphometric comparison. Journal of Hand Surgery. doi:10.1177/17531934211031862

  • Sansalone G, Allen K, Ledogar JA, Ledogar S, Mitchell, DR, Profico A, Castiglione S, Melchionna M, Serio C, Mondanaro A, Raia P, Wroe S. (2020) variation in the strength of allometry drives rates of evolution in primate brain shape. Proceedings of the Royal Society B: Biological Sciences. 287 (1930): doi:10.1098/rspb.2020.0807.

  • Leischner CL, Crouch M, Allen KL, Marchi D, Francisco P, Hartstone-Rose A. (2018) Scaling of primate forearm muscle architecture as it relates to locomotion and posture. The Anatomical Record. 301:484-495. doi:10.1002/ar.23747.

  • Boyer, D.M., Kirk, E.C., Silcox, M.T., Gunnell, G.F., Gilbert, C.C., Yapuncich, G.S., Allen, K.L., Welch, E., Bloch, J.I., Gonzales, L.A., Kaya, R.F., Seiffert, E.R., 2016. Internal carotid arterial canal size and scaling in Euarchonta: Re-assessing implications for arterial patency and phylogenetic relationships in early fossil primates. Journal of Human Evolution. 97: 123-144. doi:10.1016/j.jhevol.2016.06.002. 

  • Allen, K.L., Cooke, S.B., Gonzales, L.B., Kay, R.F. 2015. Dietary inference from upper and lower molar morphology in platyrrhine primates. PLOS One. doi: 10.1371/journal.pone.0118732.

  • Kay, R.F., Perry, J.M.G., Malinzak, M., Allen, K.L., Kirk, E. C., Plavcan, J. M., 2012. The Paleobiology of Santacrucian Primates. In: Vizcaino, S., Bargo, S., Kay, R.F., (Eds.), Early Miocene Paleobiology in Patagonia. Cambridge: Cambridge University Press.

  • Allen, K. L., Kay, R. F., 2011. Dietary Quality and Encephalization in Platyrrhine Primates. Proceedings of the Royal Society B: Biological Sciences. 279 (1729): 715-721.

  • Gongora, J., Cuddahee, R. E., do Nascimento, F. F., Palgrave, C. J., Lowden, S., Ho, S. Y. W., Simond, D., Damayanti, C. S., White, D. J., Tay, W. T., Randi, E., Klingel, H., Rodrigues-Zarate, C. J., Allen, K., Moran, C. & Larson, G., 2011. Rethinking the evolution of  extant sub-Saharan African suids (Suidae, Artiodactyla). Zoologica Scripta, 40(4), 327-335.