Factors influencing progress toward sympatric speciation
Authored by X Thibert-Plante, A P Hendry
Date Published: 2011
DOI: 10.1111/j.1420-9101.2011.02348.x
Sponsors:
National Science and Engineering Research Council of Canada (NSERC)
United States Department of Agriculture (USDA)
United States Department of Homeland Security
United States National Science Foundation (NSF)
Platforms:
No platforms listed
Model Documentation:
Other Narrative
Mathematical description
Model Code URLs:
Model code not found
Abstract
Many factors could influence progress towards sympatric speciation. Some
of the potentially important ones include competition, mate choice and
the degree to which alternative sympatric environments (resources) are
discrete. What is not well understood is the relative importance of
these different factors, as well as interactions among them. We use an
individual-based numerical model to investigate the possibilities. Mate
choice was modelled as the degree to which male foraging traits
influence female mate choice. Competition was modelled as the degree to
which individuals with different phenotypes compete for portions of the
resource distribution. Discreteness of the environment was modelled as
the degree of bimodality of the underlying resource distribution. We
find that strong mate choice was necessary, but not sufficient, to cause
sympatric speciation. In addition, sympatric speciation was most likely
when the resource distribution was strongly bimodal and when competition
among different phenotypes was intermediate. Even under these ideal
conditions, however, sympatric speciation occurred only a fraction of
the time. Sympatric speciation owing to competition on unimodal resource
distributions was also possible, but much less common. In all cases, stochasticity played an important role in determining progress towards
sympatric speciation, as evidenced by variation in outcomes among
replicate simulations for a given set of parameter values. Overall, we
conclude that the nature of competition is much less important for
sympatric speciation than is the nature of mate choice and the
underlying resource distribution. We argue that an increased
understanding of the promoters and inhibitors of sympatric speciation is
best achieved through models that simultaneously evaluate multiple
potential factors.
Tags
Evolution
sexual selection
Mutation
Mathematical-models
Ecological speciation
Intraspecific competition
Disruptive selection
Reproductive isolation
Adaptive speciation
Oceanic island