During the period of separation in allopatric speciation, divergence between populations occurs. Sometimes, before speciation is complete, the two diverging populations come back into contact (the barrier no longer keeps them apart). When this happens, explain how character displacement can influence the speciation process. During the period of separation in allopatric speciation, divergence between populations occurs. Sometimes, before speciation is complete, the two diverging populations come back into contact (the barrier no longer keeps them apart). When this happens, explain how character displacement can influence the speciation process. When this happens, explain how character displacement can influence the speciation process. When this happens, explain how character displacement can influence the speciation process. Solution Allopatric speciation or geographic speciation is speciation that occurs when biological populations of the same species gets isolated from each other to an extent that prevents or interferes with genetic interchange. This results in the evolution of new species in geographic isolation from its ancestor. Isolation of populations leading to allopatric speciation can occur in a variety of ways: a river forming a new branch, erosion forming a new valley, a group of organisms traveling to a new location without the ability to return, or seeds floating over the ocean to an island. The nature of the geographic separation necessary to isolate populations depends entirely on the biology of the organism and its potential for dispersal. If two flying insect populations took up residence in separate nearby valleys, chances are, individuals from each population would fly back and forth continuing gene flow. However, if two rodent populations became divided by the formation of a new lake, continued gene flow would be unlikely; therefore, speciation would be more likely. Character displacement refers to the phenomenon where differences among similar species whose distributions overlap geographically are accentuated in regions where the species co-occur but are minimized or lost where the species’ distributions do not overlap. This pattern results from evolutionary change driven by competition among species for a limited resource (e.g. food). When two populations which have been kept apart, come back into contact, the reproductive isolation between them might be complete or incomplete. If it is complete, speciation has occurred. If it is incomplete, hybrids would be produced. If the hybrids had lower fitness than either parental form, selection would act to increase the reproductive isolation because each form would do better not to mate with the other and form the disadvantageous hybrids. Speciation might then be speeded up by favoring genes which caused individuals to avoid mating with hybrids..

1. During the period of separation in allopatric speciation, divergence between populations occurs.
Sometimes, before speciation is complete, the two diverging populations come back into contact
(the barrier no longer keeps them apart).
When this happens, explain how character displacement can influence the speciation process.
During the period of separation in allopatric speciation, divergence between populations occurs.
Sometimes, before speciation is complete, the two diverging populations come back into contact
(the barrier no longer keeps them apart).
When this happens, explain how character displacement can influence the speciation process.
When this happens, explain how character displacement can influence the speciation process.
When this happens, explain how character displacement can influence the speciation process.
Solution
Allopatric speciation or geographic speciation is speciation that occurs when biological
populations of the same species gets isolated from each other to an extent that prevents or
interferes with genetic interchange. This results in the evolution of new species in geographic
isolation from its ancestor. Isolation of populations leading to allopatric speciation can occur in a
variety of ways: a river forming a new branch, erosion forming a new valley, a group of
organisms traveling to a new location without the ability to return, or seeds floating over the
ocean to an island. The nature of the geographic separation necessary to isolate populations
depends entirely on the biology of the organism and its potential for dispersal. If two flying
insect populations took up residence in separate nearby valleys, chances are, individuals from
each population would fly back and forth continuing gene flow. However, if two rodent
populations became divided by the formation of a new lake, continued gene flow would be
unlikely; therefore, speciation would be more likely.
Character displacement refers to the phenomenon where differences among similar species
whose distributions overlap geographically are accentuated in regions where the species co-occur
but are minimized or lost where the species’ distributions do not overlap. This pattern results

2. from evolutionary change driven by competition among species for a limited resource (e.g.
food).
When two populations which have been kept apart, come back into contact, the reproductive
isolation between them might be complete or incomplete. If it is complete, speciation has
occurred. If it is incomplete, hybrids would be produced. If the hybrids had lower fitness than
either parental form, selection would act to increase the reproductive isolation because each form
would do better not to mate with the other and form the disadvantageous hybrids. Speciation
might then be speeded up by favoring genes which caused individuals to avoid mating with
hybrids.