Question

Adult male humans generally have deeper voices than do adult female humans, which is the direct result of higher levels of testosterone causing growth of the larynx. If one excludes the involvement of gender in the situation, then the pattern that is apparent in the fossil record is most similar to one that should be expected from A) pansexual selection. B) directional selection. C) disruptive selection. D) stabilizing selection. E) asexual selection g.

Answer 1

C) disruptive selection

Step-by-step explanation:

Disruptive selection is the natural selection that favors two extreme phenotypes but does not favor the intermediate phenotype. Here, the survival and reproductive success of two extreme phenotypes are higher than that of the intermediate phenotype due to their higher fitness value in the prevailing conditions. The presence of deeper voices in males and less deep voices in females due to high and low levels of testosterone respectively represents the disruptive selection as the phenotype present at two extreme ends are favored.

Answer 2

Option C, disruptive selection

Step-by-step explanation:

Disruptive selection selects features and traits which are against the average population. The population would have extreme phenotypes but nothing in middle of that and hence could lead to deviation.

The higher percentage of male human population has deeper voice as dominant characteristics. The intermediate male population with a finer or less deep voice is small. As per the disruptive selection theory, the traits at the extremities are favored more over and above the mediocre traits and hence intermediate species (males with less deep or fine voice) will compete among themselves to produce species with ability on the extremes i.e deep voice or with higher level of testosterone.

Hence, option C is correct