Pages from 665649.pdf (726.73 kB)
Download filePopulation Regulation and Character Displacement in a Seasonal Environment
journal contribution
posted on 2014-04-15, 00:00 authored by Emma E. Goldberg, Russell Lande, Trevor D. PriceCompetition has negative effects on population size and
also drives ecological character displacement, that is, evolutionary
divergence to utilize different portions of the resource spectrum.
Many species undergo an annual cycle composed of a lean season
of intense competition for resources and a breeding season. We use
a quantitative genetic model to study the effects of differential reproductive
output in the summer or breeding season on character
displacement in the winter or nonbreeding season. The model is
developed with reference to the avian family of Old World leaf warblers
(Phylloscopidae), which breed in the temperate regions of Eurasia
and winter in tropical and subtropical regions. Empirical evidence
implicates strong winter density-dependent regulation driven
by food shortage, but paradoxically, the relative abundance of each
species appears to be determined by conditions in the summer. We
show how population regulation in the two seasons becomes linked,
with higher reproductive output by one species in the summer resulting
in its evolution to occupy a larger portion of niche space in
the winter. We find short-term ecological processes and longer-term
evolutionary processes to have comparable effects on a species population
size. This modeling approach can also be applied to other
differential effects of productivity across seasons.
Funding
Work was supported by National Science Foundation grants DEB-0919089 and DEB-1120279 (E.E.G.) and a Royal Society Research Professorship (R.L.).
History
Publisher Statement
This is a copy of an article published in the American Naturalist © 2012 University of Chicago PressPublisher
University of Chicago PressLanguage
- en_US