A Major River Changes Course and Divides a Population of Rabbits

question 8

Essay

A major river changes course and divides a population of rabbits into two subpopulations.The two groups are reproductively isolated from each other and become subjected to different selective pressures in the two locations.A predator exists on one side of the river but not the other.Over time,the two groups evolve enough that during a drought that temporarily allows the groups to once again intermingle,they can no longer reproduce with each other.What has happened in this example?

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Definitions:

Conditioned Response

A learned response to a previously neutral stimulus that has become associated with an unconditioned stimulus.

Extinction

In psychology, the diminishing of a conditioned response when the reinforcement is withheld or the stimulus is repeatedly presented without the unconditioned stimulus.

Generalization

The process of applying the knowledge or response acquired from specific stimuli to similar stimuli.

Spontaneous Recovery

The return of a response that had been previously diminished, following an interval where the conditioned stimulus was not presented.