In sperm competition, what is 'second-male advantage'?
a. The observation that when females mate with two males, each male fertilizes the same number of eggs
b. The observation that when females mate with two males, the second male fertilizes most of the eggs
c. The observation that females routinely mate with at least two males before laying eggs or becoming pregnant
d. The observation that accessory fluids prevent matings by second males—for example, by forming copulatory plugs

Question

In sperm competition, what is 'second-male advantage'?

a. The observation that when females mate with two males, each male fertilizes the same number of eggs

b. The observation that when females mate with two males, the second male fertilizes most of the eggs

c. The observation that females routinely mate with at least two males before laying eggs or becoming pregnant

d. The observation that accessory fluids prevent matings by second males—for example, by forming copulatory plugs

Accepted Answer

Hi everyone. Here's our next problem. During sperm competition. Two or more somber mazzo from different males compete to fertilize the same egg. It can occur when the female has multiple potential mating partners which the following states the downside of this process for each individual male. So let's look through our answer choices. Choice A. Says it decreases the chance for the individual male to produce offspring. Well this is correct because since there's just a single egg the chances are obviously quite high that one individual male will not be able to produce offspring because the egg will be fertilized by the other sperm. So the downside for the male is that it decreases the chance for that individual male to produce offspring. Let's just quickly glance at the other answer choices. Choice B. Says it increases the chance for an individual male to fertilize the egg. Well this is not correct because uh the competition among the different sperm obviously reduces the chance that any single sperm can fertilize it. Choice C says it increases the chance of producing non viable offspring. Well this is not our answer because only a single sperm is allowed in. Um You might have problems if both sperm could get in. Um But it doesn't say that it increases that those odds. Just that the two are competing as to which will fertilize the egg. And Choice d it can trigger a number of mutations in the resulting offspring. Well that's not our answer. Um We would not expect that from this process. Since only one sperm is allowed in. Um As usual we'll see you in the next video.

Verified video answer for a similar problem:

Key Concepts

Sperm Competition

Second-Male Advantage

Copulatory Plugs