The use of 3D Models to Study Growth and Development in Extant African Apes

AMAAZE had the privilege of scanning some primate skulls for research that was recently published in the Journal of Anatomy by Drs. Katharine L. Balolia and Jason Massey

Dr. Massey earned his PhD at the University of Minnesota and is a biological anthropologist broadly trained in evolutionary anthropology. His research focuses on growth and development in extant African apes. Specifically, he is interested in the interplay between ontogeny and evolution: how can altering growth and development facilitate evolutionary change. By recording slight changes in ontogeny at the population level, he tracks changes that lead to drastic differences in the adult morphology or shape. This potentially has great utility as we identify new species in the fossil record by differences in adult morphology. By looking at population-level variation in growth and development he investigates how slight changes in the environment can affect ontogeny. By studying taxonomic levels below that of species, like subspecies, demes, and localities, he can elucidate how ecological pressures may be altering ontogeny, potentially leading to macro-evolutionary changes. In order to investigate how much variation is possible within a single species’ growth and development, he describes the process by which males and females diverge morphologically to produce sexually dimorphic anatomy. These  differences ultimately lead to males and females enacting very different roles in their social group.

To accomplish his research aims, he 3D scans the skulls of African apes and analyzes the cranial shape utilizing geometric morphometric techniques. Geometric morphometrics is a suite of multivariate statistical tools particularly suited to analyze the shape of objects while retaining their geometric integrity. Therefore, the importance of this work relies on accurate 3D representations of specimens derived from various scanning technologies. Few studies have investigated the accuracy and precision of 3D acquisition technologies in relation to the true, physical specimens. Studies such as this are important as researchers are beginning to combine data derived from many different types of 3D scanners (turn-table scanners, hand-held scanners, CT scanners, etc). Together with his colleague from the Australian National University, Dr. Massey is contributing to this body of work by testing measurements derived from physical specimens with those derived from several scanner types at varying resolutions. AMAAZE had the privilege of contributing to this project by CT scanning and post-processing key data needed to fully investigate scanner accuracy.

A photo of Dr. Jason Massey
Photo of scans of primate skulls