Geisler receives $135,000 grant for study of evolution of dolphins and porpoises

May 14, 2007

Jonathan Geisler is a paleontologist at Georgia Southern University who teaches a course on dinosaurs, so it should come as no surprise that he has a special interest in evolutionary biology.

Geisler has channeled his curiosity into a project that will try to answer some lingering questions about the evolution of Delphinida, a group of marine mammals that includes dolphins, porpoises, beluga whales and narwhals.

Supported by a $135,000 grant from the National Science Foundation (NSF), Geisler will travel to museums on four continents during the next three years to analyze the skeletons of fossil and living dolphins and porpoises.

An assistant professor in the Department of Geology and Geography and the curator of paleontology at the Georgia Southern Museum, Geisler is collaborating with John Gatesy, a molecular biologist in the Department of Biology at the University of California Riverside.

Gatesy is collecting DNA data for the study, which aims to resolve evolutionary relationships among living and extinct species.

‘Evolution is the thread that really ties all disciplines of biology together,” Geisler said. ‘So, in many ways, to gain a basic understanding of a group, one needs to understand how they are related to each other through evolution.”

To gather data for his part of the project, Geisler will visit some of the nation’s most prestigious museums, including the National Museum of Natural History in Washington, D.C., and the American Museum of Natural History in New York.

As they are today, dolphins and porpoises were distributed across the Earth’s oceans in the geologic past, so Geisler will be traveling to museums in Argentina, China, France, Italy, Japan, Peru, and the Republic of Georgia to study the most important fossil specimens.

In addition, Geisler will be teaching a course at Georgia Southern that engages undergraduates in the research aspect of his project. The students will study the teeth and skulls of actual specimens and casts in the Georgia Southern Museum’s paleontological collections.

Using the data they collect, the students will assist in reconstructing part of the evolutionary tree of dolphins and porpoises. The students will be coauthors on a manuscript that the class will submit for publication.

With the assistance of Lori Marino, a senior lecturer in the Neuroscience and Behavior Biology Program at Emory University in Atlanta, the project also seeks to determine if behavior influenced the evolution of large brains in dolphins.

‘Scientists are currently studying the evolution of brains in primates, with particular emphasis on the development of the human brain,” Geisler said. ‘One of the problems with this area of research is that there is little to compare the evolution of primate brains to.

‘Cetaceans  mammals that live their entire lives in the water  have relatively large brains, and our work will provide a case study with which to compare to the evolution of brains in primates.”

Geisler’s grant from the NSF will distributed over three years at $45,000 per year. The project is expected to run through March 2010.