A) A textbook definition would be that genetic drift is: a random change in allele frequency caused by a series of chance occurences that cause an allele to become more or less common in a population. In layman's terms, this means that genetic drift happens when luck makes the genetic pool of the population to deviate from what is expected.
B) The cause for this genetic drift is the aformentioned couple. Because amish communities are small and they select partners from their community, having even a couple of carriers of alleles in a community can make the allele freuency much larger than expected; for example, if the community was 100 persons, the percentage would be in the order of 1%, still much larger than the general population. Thus, the cause here is that a small population had a couple of carriers.
C) Sexual reproduction leads to a mixing of alleles from both mother and father and helps diversity. When a population is isolated, the gene pool is fixed and no new genes can come in, reducing diversity. Also some people that have an allele might die, hitting diversity even more. Finally, having a small population creates a strong pressure in some circumstances that leads to elimination of some traits and diversity.
Current estimations are that one in five Americans will develop skin cancer in their lifetime. It is estimated that approximately 9,500 people in the U.S. are diagnosed with skin cancer every day. Which adds up to over 3.3 million persons each year.
Hope this helps! :)
Answer:
The correct answer is B. exploitation
Explanation:
Exploitation competition occurs when the interaction of two species is indirect when they complete for the same resource like food, place, etc. The use of resources by one individual species reduces the amount of resources for the other species leading to competition.
So over time the more fit species will out complete the less fit species. So here two species of bird feed on the same food but at different times and so they reduce resources for each other which is an example of exploitation competition.
This is False
Natural selection is the mechanism in which organisms inherit the traits that are necessary for survival and thus change. Those who do not have these traits die.
