Agents of Evolutionary Change Read the following passage about the evolutionary history of a hypothetical population and fill in the letter where each agent of evolutionary change is the most likely to be the cause (not all of the possibilities listed below will be relevant in this example). Volcanic activity in the Pacific Ocean causes a new island to form. This island initially has no living residents, but after a while, droppings from passing migratory birds introduce seeds to the island. Five of these seeds come from one species of palm tree. This agent of evolutionary change has shaped the initial allele frequency on the new island D. Over time, variation in several phenotypic traits, including palm height and number of fruit produced each year, accumulate. While the ancestral palm tree from the other islands occurred in a forest and needed to be tall in order to gain access to sunlight, there are few competitors on the new island. As a result, acts such that shorter trees tend to produce more offspring on the new island. However, not all trees are short, because the sea birds still migrate between islands, which allows occasional to continue between the new island and older islands.

Agents of Evolutionary Change!

Read the following passage about the evolutionary history of a hypothetical population and fill in the letter where each agent of evolutionary change is the most likely to be the cause (not all of the possibilities will be relevant in this example).

Volcanic activity in the Pacific Ocean causes a new island to form. This island initially has no living residents, but after a while, droppings from passing migratory birds introduce seeds to the island. Five of these seeds come from one species of palm tree. This agent of evolutionary change has shaped the initial allele frequency on the new island (1). Over time, variation in several phenotypic traits, including palm height and number of fruit produced each year, accumulate. While the ancestral palm tree from the other islands occurred in a forest and needed to be tall in order to gain access to sunlight, there are few competitors on the new island. As a result, (2) acts such that shorter trees tend to produce more offspring on the new island. However, not all trees are short, because the sea birds still migrate between islands, which allows occasional (3) to continue between the new island and older islands.

Options:-

a. Natural Selection

b. Artificial Selection

c. Sexual Selection

d. Genetic Drift

e. Gene Flow

f. Mutation

1.d 2.a 3.e

Explanation:

The task at hand is to explore and write the correct agent of evolutionary change in the hypothetical population in the text above.

We see as biotic and abiotic interaction occurs on a virgin land created by the volcanic eruption, succession happens with speciation and diversity characterising the population. This gives rise to an inter and intra-population phenomenon that gives rise to evolutionary changes.

Terminology in the light of evolutionary changes as stated in the options are defined thus;

Natural selection is phenomenon that happens in a population where each species shows variation. There is competition within each species for food, living space, water, mates etc. The "better adapted" members of these species are more likely to survive "Survival of the Fittest". These survivors will pass on their better genes to their offspring who will also show this beneficial variation.

Artificial selection also known as selective breeding phenomenon involves intentional breeding of preferred plants or animals in a population.

Sexual selection is a form of natural selection. This phenomenon explains and shows how animals in a population compete with others of the same species for mate

d

explanation: