« previous next »

Author Question: Adult male humans generally have deeper voices than do adult female humans, whic (Read 845 times)

Garrulous

  • Hero Member
  • *****
  • Posts: 686
on: Jul 9, 2013
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 the fossil records of apes and humans alike show a trend toward decreasing larynx size in adult females and increasing larynx size in adult males, then
A) sexual dimorphism was developing over time in these species.
B) intrasexual selection seems to have occurred.
C) stabilizing selection was occurring in these species concerning larynx size.
D) selection was acting more directly upon genotype than upon phenotype.


Hawke

  • Hero Member
  • *****
  • Posts: 679
Reply #1 on: Jul 10, 2013
Hello

A is the answer.


Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
« previous next »
 

Did you know?

Every 10 seconds, a person in the United States goes to the emergency room complaining of head pain. About 1.2 million visits are for acute migraine attacks.

Did you know?

Side effects from substance abuse include nausea, dehydration, reduced productivitiy, and dependence. Though these effects usually worsen over time, the constant need for the substance often overcomes rational thinking.

Did you know?

Interferon was scarce and expensive until 1980, when the interferon gene was inserted into bacteria using recombinant DNA technology, allowing for mass cultivation and purification from bacterial cultures.

Did you know?

Adolescents often feel clumsy during puberty because during this time of development, their hands and feet grow faster than their arms and legs do. The body is therefore out of proportion. One out of five adolescents actually experiences growing pains during this period.

Did you know?

Individuals are never “cured” of addictions. Instead, they learn how to manage their disease to lead healthy, balanced lives.

The bobcat population has seen declines in the American Midwest, but is generally stable and healthy The bobcat population has seen declines in the American Midwest, but is generally stable and healthy
The S-curve in the human vertebral column--a result of the evolution of bipedality--makes humans hig The S-curve in the human vertebral column--a result of the evolution of bipedality--makes humans hig
Sample Diet for a College-Aged Female Weighing 132 Pounds, Assuming Light to Moderate Daily ... Sample Diet for a College-Aged Female Weighing 132 Pounds, Assuming Light to Moderate Daily ...
Hormonal control over male and female reproductive hormones. Hormonal control over male and female reproductive hormones.
Female Reproductive System - Mature (graafian) follicle "الجهاز التناسلي ... Female Reproductive System - Mature (graafian) follicle "الجهاز التناسلي ...
Video: Sigmoidoscopy

For a complete list of videos, visit our video library