Problem :
Describe the mechanism of adaptive radiation.
An adaptive radiation is a burst of evolution, creating several new species out
of a single parent species. A population of species, 1, moves into a new
habitat and establishes itself in a niche, or role, in that habitat. While
there, it adapts to its new environment and becomes different from the parent
species. Next, a new population of the parent species, 2, moves into the area,
trying to occupy the same niche as 1. Because of the niche rule, which states
that only one of a group of closely related species may occupy the a niche in a
given habitat, competition between 1 and 2 places pressure on both groups to
adapt to separate niches. In this process, each becomes further distinguished
from each other and the parent species. A third or even more populations of the
parent species may move into the area, causing several different species to
arise from the same parent species.
Problem :
How does adaptive radiation help account for the diversity of life on earth?
Adaptive radiations create many new species out of a single species in a
relatively short period of time. If all speciation took place by creating one
or two new species out of a parent species, we would not expect to see the
number of species we do today.
Problem :
Explain the Niche Rule.
The Niche Rule states that no two closely related species may occupy the same
niche in a given habitat. Competition between the two species will be so
intense that each will evolve to be different from the other and able to occupy
a different niche.