| | |
Summary: Interspecific population regulation and the stability of mutualism:
fruit abortion and density-dependent mortality of pollinating
seed-eating insects
J. N. Holland, Dept of Ecology and Evolutionary Biology, Rice Univ., MS-170, 6100 S. Main St., Houston, TX 77005,
USA (jholland@rice.edu). Á D. L. DeAngelis, US Geological Survey/Biological Resources Division and Dept of
Biology, Univ. of Miami, Coral Gables, FL 33124, USA.
Two questions central to the population ecology of mutualism
include: (1) what mechanisms prevent the inherent positive
feedback of mutualism from leading to unbounded population
growth; and (2) what mechanisms prevent instability from arising
due to overexploitation. Theory and empiricism suggest that
preventing such instability requires density-dependent processes.
A recent theory proposes that if benefits and costs to a mutualist
vary with the density of its partner, then instability can be
prevented if the former species can control demographic rates and
regulate (or limit) the population density of its partner. The
ecological and evolutionary feasibility of this theory of
interspecific population regulation has been demonstrated using
quantitative models of mutualism between plants and pollinating
seed-consuming insects. In these models, resource-limited fruit set
|
