Question

Salmon live in the ocean as adults but return to freshwater streams to reproduce. Female salmon lay between 1,000 and 17,000 eggs, but most do not survive due to predators and harsh conditions.

What is the advantage of salmon laying so many eggs?
A
Having a large number of offspring encourages competition for finite resources.
B
Having a large number of offspring promotes the chance of favorable mutations.
C
Having a large number of offspring allows for more gene flow between populations.
D
Having a large number of offspring increases the chances that some will survive.

Answer 1

D

Laying many eggs is an r-selected strategy: because most offspring die from predation and harsh conditions, producing large numbers increases the probability that some will survive to reproduce.