According to Hamilton's rule, a. natural selection does not favor altruistic behavior that causes the death of the altruist. b. natural selection favors altruistic acts when the resulting benefit to the recipient, corrected for relatedness, exceeds the cost to the altruist. c. natural selection is more likely to favor altruistic behavior that benefits an offspring than altruistic behavior that benefits a sibling. d. the effects of kin selection are larger than the effects of direct natural selection on individuals.

Video transcript

Hello everyone. Let's look at our next problem. Well this starts with a statement and says natural selection favors altruistic acts when the resulting benefit to the recipient corrected for relatedness exceeds the cost of the altruist. This statement is accordance with. Well again that's kind of wordy. Let's tease that out and recall from our content video. Um This is talking about when could natural selection favor something an altruistic act meaning something that might cause a disadvantage to the individual or that individuals offspring. Um So when could natural selection actually favor something altruistic? Uh This is saying if the benefit to the recipient corrected for relatedness. So this covers behaviors like ants helping to feed nieces because the aunt and niece are related share a certain number of genes. So you'd still see a benefit. So for relatives due to the shared DNA relatives helping other relatives. Even if not direct offspring. Even to a slight detriment to oneself or one's offspring can still be favored by natural selection. And that will depend obviously on the degree of relatedness. The closer the relative the more strongly natural selection can favor altruism. And we can recall from our condom videos that this is a choice. A Hamilton's rule. That's the definition of Hamilton's rule. That's the correct match but to be thorough in case you get asked about the other ones. Let's just walk through the other population ecology rules listed here. Charge offs rule. Well that's completely unrelated to this. Charge rule has to do with D. N. A. And that's what states that we'd expect to see in DNA molecule. An equal ratio of C. Two G. Bases and a two T. Bases. That was what led to our discovery of this structure of D. N. A. But not what we're looking for here. Choice C. Is the hardy Weinberg rule. And that has to do with um a little and genotype frequencies in a population. So saying that if we have no other evolutionary pressure that the frequencies of certain aliens and Jenna types will remain constant in the population from generation to generation minus outside evolutionary pressures. But not having to do with altruistic acts. So not our choice and choice D. Is the product rule. Um That has to do with probability. Just saying the probability of two unrelated events both happening is equal to the product of the probability of each. So we use that in population ecology. We use that in genetics to say look at the probability of certain um certain genomes. When you think of your punnett square, like what's the probability of a P being yellow and wrinkled? We multiply the probability of the P being yellow by the probability of the p being wrinkled and the probability of both of those things is the product of that. But not having to do with altruistic acts. Not our choice here. So again, choice A Hamilton's rule is about the occasions when natural selection can favor altruistic acts due to the relatedness of the altruist and the recipient. Thanks for watching