In many bird species, the number of eggs laid is negatively correlated with the survival of the young.At the extreme of very large clutch sizes, hardly any of the young survive.Clutch size variation is largely due to genetic factors.In light of this, which statement is most likely to be true?
A) This represents a case of heterozygote advantage, and selection should favor very large clutches.
B) This represents a case of heterozygote advantage, and selection should favor intermediate-sized clutches.
C) This is an example of a trade-off, and selection should favor very large clutches.
D) This is an example of a trade-off, and selection should favor intermediate-sized clutches.
E) Selection would not be expected to affect clutch size.

Question

Quizplus · Accepted Answer

The negative correlation between clutch size and survival of young suggests a trade-off between producing many offspring and investing resources in their survival. Genetic factors play a large role in determining clutch size, so there is potential for selection to act on these genes. However, favoring very large clutches would likely result in low survival rates, so intermediate-sized clutches that balance reproductive output with offspring survival are most likely to be favored by natural selection.

In Many Bird Species, the Number of Eggs Laid Is