Question

Human birth weights range very narrowly between 5.5 and 8.5 pounds. Babies much smaller than 5.5 lbs. suffer a higher mortality due to low birth weight, while babies much larger than 8.5 lbs. can cause complications during birth and also have a higher mortality rate. This is an example of:a. Stabilizing selection b, Sexual selection c. Genetic drift d. Reproductive isolation e. Disruptive selection

Answer 1

Answer:

a.  Stabilizing selection

Explanation:

Babies lower than 5.5lbs would suffer from various disorder because of low birth weight as their body would not be able to compete as well they would have weak immune system and malnourishment. Whereas high birth weight carry the equally above risk as their body wont be able to cope up and organs become insensitive to various hormones. for the survival the birth weight should be within a median range so that it would be favorable for themselves and surroundings.

Stabilizing selection occurs when a population stabilizes on a particular trait value and genetic diversity decreases. As in this example, an average baby weight has to favour against extreme variation for it's better survival.

therefore, this is an example of stabilizing selection.