Functional morphology of the primate vertebral column
Research in the Nalley Lab focuses on the biomechanics of primate locomotion, specifically the relationships among the vertebral column, skull, and the pectoral girdle. Using comparative morphology and locomotor modeling, our research investigates the evolution of bipedality in the human lineage, as well as the historical patterns of positional behavior in living and fossil primates. Related areas of research include examining musculoskeletal plasticity in the vertebral column and how behavior and ontogeny influence adult vertebral morphologies at both the microscopic and gross levels.
Human ancestors and the evolutionary history of the human vertebral column
We aim to identify phylogenetic and ontogenetic differences across the entire vertebral column in humans, apes, and fossil species.
Subadult Australopithecus afarensis specimen, DIK 1-1. (A) Photograph of the DIK-1-1 vertebrae in block with skull, pectoral girdle, and rib fragments before complete preparation. The vertebral column is highlighted. (B) Entire articulated cervical and thoracic column of DIK-1-1, with vertebral levels indicated on each bone, demonstrating the presence of seven cervical and 12 thoracic (rib-bearing) vertebrae. Most of these vertebrae cannot be disarticulated mechanically. (C) The three caudal-most preserved vertebrae—T10, T11, and T12—with rib facets indicated (arrows) on T11 and T12.
3D surface model of a subadult orangutan. Surface models of infant and juvenile ape skeletons are being scanned and archived in Dr. Nalley’s lab for comparative work on the growth and development of fossil human ancestors.
Functional morphology of primate cervical vertebrae, basicranium, and shoulder
We investigate the function-form relationships between cranial shape, cervical bony and soft tissue morphologies, and positional behaviors to better understand adaptation in living primates and to aid reconstructions of behavior in fossil taxa.
3D rendering of contrast-enhanced microCT scans of a tarsier primate. These data are part of a larger comparative project investigating adaptation and in situ relationships between bony and soft tissue structures in the primate neck.
Three-dimensional surface model of juvenile chimpanzee C1 with 3D coordinate landmarks used to quantify functional aspects of joint shape.
i. Ward CV, Nalley TK, Spoor F, Tafforeau P, Alemseged Z. 2017. Thoracic Vertebral Count and Thoracolumbar Transition on Australopithecus afarensis. Proceedings of the National Academy of Sciences of the United States of America. Jun 6;114(23):6000-6004. DOI: 10.10073/pnas.1702229114.
ii. Nalley TK, Grider-Potter N. 2017. Functional analyses of the primate upper cervical vertebral column. J Hum Evol. 2017. Jun:107:19-35. doi 10.1016/jhevol.2017.03.010.
iii. Nalley TK, Grider-Potter N. 2015. Cervical vertebrae morphology and its relationships to head and neck posture in primates. Am J Phy Anthropol 156 (4), p 531-542.
iv. Nalley TK, Lewton KL. 2015. From the Ground Up: Integrative Research in Primate Locomotion. Am J Phy Anthropol 156 (4), p 495-497