Brian T. Shea
Title: Professor
Research area: Primate Development, Morphology and Evolution
Degree: Ph.D.
Voice:312.503.6911
Fax: 312.503.7912
E-mail: b-shea@northwestern .edu

Detailed research description:
Changes in body size during the evolutionary diversification of organisms can exert profound influences on their morphology and physiology. A good understanding of evolutionary processes and relationships requires elucidating the biomechanical constraints imposed by such size shifts as well as the ways in which ancestral patterns of ontogenetic size and shape changes are modified to yield evolutionary transformations.

My research focuses on the control of allometric patterns in the skeleton during later morphogenesis. The effects of growth hormone (GH), insulin-like growth factor 1 (IGF1), and other growth factors on skeletal morphogenesis are being investigated through use of giant transgenic mice, size-selected mice, several strains of mutant dwarf mice, various groups of anthropoid primates, African and Asian Pygmy humans, and other models of growth disturbances. These studies help to clarify aspects of the intrinsic and extrinsic control of growth and body proportions and the types of morphological and timing changes that frequently accompany size diversification in evolutionary lineages. Results have demonstrated that minor shifts in certain growth controls yield marked but predictable morphological transformations among groups or species via characteristic changes in common underlying patterns of morphogenesis. Studies of heterochrony in primates and other organisms are designed to provide insights into the relationships between ontogeny and phylogeny.

Another investigation focuses on the form, function, and evolution of the skull and postcranium in primates, particularly in monkeys and apes. This work involves qualitative and quantitative analyses of structural transformations in musculoskeletal morphology during the past 20 to 30 million years, focusing on both extant and fossil taxa. Morphometric and systematic analyses of humans and African apes have contributed to our understanding of the phylogenetic relationships among the living apes and their much more diverse Miocene relatives.