(Posted January 10, 2011)

HUNTINGDON, Pa. -- Although it seems a no brainer, the question of why species are more diverse at the equator than nearer the poles has never been completely answered. Matt Powell, assistant professor of geology at Juniata College, will address that topic in the lecture "The Fossil Record of the Latitudinal Diversity Gradient," at 4:30 p.m., Wednesday, Jan. 19, in Neff Lecture Hall in the von Liebig Center for Science on the Juniata campus.

The talk is free and open to the public. The Bookend Seminar series features afternoon lectures each month by Juniata College faculty.

Powell will demonstrate during the talk that biodiversity (the variety of life and species in a habitat or ecosystem) generally increases from the poles toward the equator. This increase in species from the colder poles to the warmer tropical equator is known as the latitudinal diversity gradient.

This diversity gradient has been recognized since 1808, when Alexander von Humboldt proposed that life at high latitudes was restricted to species that "can sustain a protracted interruption of their vital functions" during the freezing temperatures.

Two centuries later, scientific documentation of the basic pattern (that biodiversity is highest in the tropics) has improved, but scientists' understanding of why it exists has not. Powell will discuss how recent work on the fossil record of the latitudinal diversity gradient challenges some of the major assumptions regarding the present-day gradient, and suggest a possible cause for the diversification of species toward the equator.

Powell joined the Juniata College faculty in 2007 as an assistant professor of geology. Previously, he worked as a Humboldt Postdoctoral Fellow at the Alexander von Humboldt Foundation at Johann Wolfgang Goethe University in Frankfurt, Germany from 2006 to 2007.

Powell earned a bachelor's degree in biology in 1998 from Virginia Polytechnic Institute and State University in Blacksburg, Va. and went on to earn a master's degree at Virginia Tech in geological sciences in 2000. He earned a doctoral degree in earth and planetary sciences in 2005 from The Johns Hopkins University in Baltimore, Md.

From 2005 to 2006, he was a visiting assistant professor of geology at Washington and Lee University in Lexington, Va. He has taught a variety of courses, including general geology, history and evolution of the earth and oceanography.

As a researcher, Powell is interested in looking at the invertebrate fossil record to see biogeographic patterns of evolution. His specific area of expertise centers on the effects the late Paleozoic Ice Age had on the ecology and evolution of brachiopods.

He has had his research published in a variety of professional journals, including Global Ecology and Biogeography, Geology, and Paeleobiology.

He is a member of a number of professional organizations, including the Geological Society of America, the Paleontological Society, the International Biogeography Society and the American Geophysical Union.

Contact April Feagley at feaglea@juniata.edu or (814) 641-3131 for more information.