Dr. Fangliang He is part of a research team that studied fundamental questions plaguing scientists since Darwin's time: why are some species so common while others are rare? How do common and rare species interact? And how do hundreds, even thousands, of tree species coexist in a limited space in the tropics?

He, along with Igor Volkov and Jayanth Banavar, from Pennsylvania State University, Stephen Hubbell from the University of Georgia and Amos Maritan from the Universita di Padova in Italy, offer a new theory to explain why tropical rain forests are so species rich and how species are assembled in a community. Their work is published in the current edition of "Nature".

Species must meet certain conditions to live in a community. Understanding the rules that make up community assemblages is one of the most challenging scientific questions facing scientists today. Niche theory, which assumes species differ from one another in various aspects, has been traditionally used to explain community assemblages. However, this theory offers little to predict community assemblage patterns the way species share a limited space.

He's work attempts to address community assembly rules based on Hubbell's recently developed neutral theory. "The basic idea of the neutral theory is that community membership is determined by five fundamental processes: birth, death, immigration, speciation and random drift. Furthermore, the theory assumes that every individual in the community, regardless of species identity, has the same rates of birth, death, immigration and mutating into a new species," said He, who is a Canada Research Chair from the Department of Renewable Resources.

The research team modified
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Contact: Phoebe Dey
phoebe.dey@ualberta.ca
780-492-0437
University of Alberta
30-Nov-2005