Question

13) The best evident to support the idea that whales and hippos share a common terrestrial ancestor is based on A. the habitat homology of their propensity toward water B. genetic homology in the SINE regions C. development homology of the embryonic structures D. structural homology of their ankle bones

14) Which of the following is a fitness tradeoff that we discussed in class? A. development of sweat glands to handle the heat B. the tailbone in humans C. humans giving birth early so they can better pass through the birth canal D. development of melanin in humans to handle the UV rays

15) Both the founder event and genetic bottlenecking A. Increase the genetic variability of a new population after the event. B. Always lead to extinctions. C. Decrease the genetic variability of a new population after the event. D. Are always caused by natural disasters.

Answer 1

Ans 13. A

Hairlessness and Glands One notable similarity between the two groups is minimal hair -- both hippos and whales have barely any hair on their bodies. They also do not have sweat glands. These are both things that can assist them in their aquatic lifestyles. Hippos evolved from a group of anthracotheres about 15 million years ago, the whales evolved from their common ancestor over 50 million years ago. This common ancestor was terrestrial, so it is remarkable that it gave rise to two different types of aquatic mammals, one marine and one freshwater

Ans 14.A.

The definition of trade off is an exchange where you give up one thing in order to get something else that you also desire.

Ans 15.C

In population genetics, the founder effect is the loss of genetic variation that occurs when a new population is established by a very small number of individuals from a larger population.A population bottleneck may also cause a founder effect, though it is not strictly a new population.