Dispersal, whether in the form of a dandelion seed drifting on the breeze, or a salmon migrating upstream to breed in a nonnatal stream, transports genes between locations. At these locations, local adaptation modifies the gene frequencies so their carriers are better suited to particular conditions, be those of newly disturbed soil or a quiet river pool. Both dispersal and local adaptation are major drivers of population structure; however, in general, their respective roles are not independent and the two may often be at odds with one another evolutionarily, each one exhibiting negative feedback on the evolution of the other. Here, we investigate their joint evolution within a simple, discrete-time, metapopulation model. Depending on environmental conditions, their evolutionary interplay leads to either a monomorphic population of highly dispersing generalists or a collection of rarely dispersing, locally adapted, polymorphic sub-populations, each adapted to a particular habitat type. A critical value of environmental heterogeneity divides these two selection regimes and the nature of the transition between them is determined by the level of kin competition. When kin competition is low, at the transition we observe discontinuities, bistability, and hysteresis in the evolved strategies; however, when high, kin competition moderates the evolutionary feedback and the transition is smooth.
@article{berdahl_evolutionary_2015,
Author = {Berdahl, Andrew and Torney, Colin J. and Schertzer,
Emmanuel and Levin, Simon A.},
Title = {On the evolutionary interplay between dispersal and
local adaptation in heterogeneous environments},
Journal = {Evolution},
Volume = {69},
Number = {6},
Pages = {1390--1405},
Note = {WOS:000356675400003},
Keywords = {Adaptive radiation, define fitness, dimorphic
populations, disruptive selection, evolutionary
branching, inbreeding avoidance, joint evolution, joint
evolution, kin competition, meta-population,
metapopulation, patchy environments, seed dispersal,
selective interactions, specialization, strategies},
abstract = {Dispersal, whether in the form of a dandelion seed
drifting on the breeze, or a salmon migrating upstream
to breed in a nonnatal stream, transports genes between
locations. At these locations, local adaptation
modifies the gene frequencies so their carriers are
better suited to particular conditions, be those of
newly disturbed soil or a quiet river pool. Both
dispersal and local adaptation are major drivers of
population structure; however, in general, their
respective roles are not independent and the two may
often be at odds with one another evolutionarily, each
one exhibiting negative feedback on the evolution of
the other. Here, we investigate their joint evolution
within a simple, discrete-time, metapopulation model.
Depending on environmental conditions, their
evolutionary interplay leads to either a monomorphic
population of highly dispersing generalists or a
collection of rarely dispersing, locally adapted,
polymorphic sub-populations, each adapted to a
particular habitat type. A critical value of
environmental heterogeneity divides these two selection
regimes and the nature of the transition between them
is determined by the level of kin competition. When kin
competition is low, at the transition we observe
discontinuities, bistability, and hysteresis in the
evolved strategies; however, when high, kin competition
moderates the evolutionary feedback and the transition
is smooth.},
doi = {10.1111/evo.12664},
issn = {0014-3820},
language = {English},
month = jun,
year = 2015
}
