EVOLUTION OF THE AUDITORY COMPLEX OF MYSTICETI (CETACEA): PHYLOGENETIC AND MORPHOLIGIC EVIDENCE FROM TOOTHED, EDENTULOUS ?CETOTHERE?, AND EXTANT BALEEN WHALES

San Diego State University Foundation, San Diego CA

Investigators

Abstract

This project will reconstruct the evolutionary relationships among baleen whales (mysticetes) spanning 34 million years of Earth History through detailed anatomical comparisons using state of the art technologies, including high resolution CT images. The phenotypic focus is anatomy associated with low frequency hearing. It is unknown if extinct species were as sensitive to low frequency sounds as are their living descendants. Some fossil mysticetes share ear morphology similar to living whales, but hypotheses of when or how many times morphologies associated with auditory physiology evolved throughout mysticete phylogeny remain unresolved and will be studied using phylogenetic comparative methods. The novel morphologic descriptions and analyses produced by the research will add important new information concerning the anatomical structures involved with hearing perception, and it will also lead to an increased comprehension of the effect of human activities on living whales. In addition, the data will form a foundation for newly developed science curricula for public schools through provision of novel data to California educators for use in the classroom.