1. Imagine you are doing a summer internship as a research assistant at Mountain

Question

1. Imagine you are doing a summer internship as a research assistant at Mountain Lake Biological Station in Virginia. During your internship you observe two distinct species of butterflies in the area. They have similar body shapes and they both drink nectar. But their color patterns are different; one is bright green and one is dark green. You further observe that their habitat ranges overlap, but are distinct in that the dark green butterfly prefers shady, cool forest interiors while the bright green butterfly prefers sunny meadows. Both species are camouflaged well in their respective habitats. You have seen both species preyed upon by birds. Finally, the population size of the two species is about equal. Based on the information given, was the evolution of these two species of butterflies more likely due to natural selection or genetic drift? Write an answer in which you concisely define both mechanisms, state which evolutionary mechanism is more likely and logically explain why.   

   2.You are studying a population of cheetahs and discover that across most loci you find fewer heterozygotes than expected and more homozygotes. What are two possible explanations of this result? What impact might this have on population fitness? This answer can be brief, not a long essay.

Explanation / Answer

1. Both natural selection and genetic drift are driving force of evolution. But the key distinction is that:

A) Genetic drift causes changes in allele frequencies in a small population by chance. This may happen when a random proportion of a small population dies due to some catastrophic events or anthropogenic disturbances. The remaining individuals passes their traits to future generations,

B) Natural selection is a nonrandom process which causes changes in allele frequencies in large population change not by chance but by differential reproductive success. If a trait has an increased an organism's ability to reproduce, then that trait will be more likely to pass to the next generation. It is the process where these adaptive traits become more common in a population.

Now in the given information it provided that:

2) The increased homozygotes than heterozygotes in population of cheetah might be due to :

Both genetic drift and inbreeding decreases the biological fitness of the population

Related Questions

Navigate

• Browse (All)
• Browse 1
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.