University of Wisconsin-Madison Skip navigationDepartment of Physics Search Site Map UW Home


UW Home Page


This Week at Physics

Physics Events this

Colloquia & Seminars

Physics Department

Astronomy Colloquia

Chaos & Complex
Systems Seminars

College of Engineering

High Energy Seminars

Medical Physics

NPAC Forums

Physics Department

"Physics Today"

Physics/ECE/NE 922

R. G. Herb Materials
Physics Seminars

String Theory Seminars

Theory/Phenomenology Seminars

Wonders of Physics

Department of Physics
Colloquia & Seminars

Physics Department Colloquium
Anticipating sudden transitions in biological populations Cooperation, cheating, and collapse
Time: 3:30 PM
Place: 2241 Chamberlin Hall (coffee at 430 pm)
Speaker: Jeff Gore, Massachusetts Institute of Technology
Abstract: Natural populations can suffer catastrophic collapse in response to small changes in environmental conditions, and recovery after such a collapse can be exceedingly difficult. We have used laboratory microbial ecosystems to study early warning signals of impending population collapse. Yeast cooperatively breakdown the sugar sucrose, meaning that below a critical size the population cannot sustain itself. We have demonstrated experimentally that changes in the fluctuations of the population size can serve as an early warning signal that the population is close to collapse. The cooperative nature of yeast growth on sucrose suggests that the population may be susceptible to cheater cells, which do not contribute to the public good and instead merely take advantage of the cooperative cells. We confirm this possibility experimentally and explore how such social parasitism can lead to population extinction.
Host: Gilbert
Download video

Do you have questions? Oh yes you do!
Contact (access restricted)

  $Id:,v 1.1 2011/10/25 17:40:19 rader Exp $