Experimental Studies of Extinction Dynamics
Gary E. Belovsky,
*
Chad Mellison,
Chad Larson,
Peter A. Van Zandt
Extinction of populations occurs naturally, but global extinction
rates are accelerating, making understanding extinction a high priority
for conservation. Extinction in experimental populations of brine
shrimp (Artemia franciscana) was measured to assess
hypothesized extinction processes. Greater initial population size,
greater maximum population size supported by the environment, and lower variation in environmental conditions reduced the likelihood of extinction, as hypothesized. However, initial population size was less
important, and maximum population size and environmental variation were
more important than often hypothesized. Unexpectedly, deterministic
oscillations in population size due to inherent nonlinear dynamics and
overcrowding were as important or more important than hypothesized
processes.
Department of Fisheries and Wildlife and Ecology Center, Utah
State University, Logan, UT 84321, USA.
*
To whom correspondence should be addressed. E-mail:
Belovsky{at}cc.usu.edu
Present address: Biology Department, University of Louisiana,
Lafayette, LA 70504, USA.
