A small population of a specific bird species lives on an island in the Pacific Ocean. All of the birds of this species have a c
rest of feathers on their heads. The color of the crest can be orange, yellow, or white. An individual's crest color does not effect its chance of survival or its reproductive success. A hurricane hits the island and all of the birds with orange crests are killed, as well as many of the individuals with yellow and white crests. This causes the gene for orange crests to be lost from the population. The loss of the gene coding for an orange crest in the bird population described above is an example of _______.
Genetic drift is an evolutionary mechanism that changes the allele frequency by random sampling (by chance). This type of mechanism has the major impact when population is hit by a natural disaster. As a consequence, the population becomes reduced in size and some alleles might be lost (such as that for for orange crests). The genetic variability is decreased.
Genetic drift is a change in the allelic frequency within a population due to random chance. It is especially apparent within small breeding populations. For example, genetic drift can result in an allele being completely lost from a population by random chance, regardless of whether the allele has any effect on an individual's chance of survival or its reproductive success. (got it right on study island)
Stanley Miller is the scientist that is credited with the idea that
early life formed through a successions of chemical reactions that make simple
compounds more complex. He made a breakthrough of experiments in the origin of
life by representing that a wide range of vital organic compounds can be produced
by fairly simple chemical processes from inorganic substances. Although he
worked with Urey on this experiment, Miller is far more well-known and credited
for the discovery.