FE17

Question 1

Research demonstrates that humans are more likely to mate with individuals who have MHC alleles that differ from their own than would be expected if people selected their mates at random.
a) Drawing on the readings for this course, summarize basic findings from one empirical study that are consistent with this (you do not need to identify the researchers). Be sure to identify what phenotypic feature appears to be involved in this effect

Answer 1

• Tshirt sniffing tests.

* Olfaction (phenotypic feature

Question 2

Suppose it were found that, among pre-industrial societies, controlling for the level of MHC diversity in the local population, sexual relationship partners in relatively densely populated equatorial regions tend to share fewer MHC alleles with each other (i.e., they are more MHCdissimilar) than relationship partners in more sparsely populated areas closer to the poles. Provide an ultimate explanation for this hypothetical pattern

Answer 2

• Because there’d be fewer mating choices to pick from

Question 3

There is indirect evidence that oral contraceptives alter a woman’s preferences with regard to the preferred degree of MHC similarity. Drawing on material in lecture, briefly describe this evidence, and provide an ultimate explanation for the mechanism thought to underlie this pattern

Answer 3

• Tshirt sniffing was only true women not taking hormonal contraceptives. These women preferred tshirts of men that were similar to themselves
• The pill was flatlining the ovulation; if you’re just judging scent with regard to something other than the genetic compatibility, then you’re just judging scent for cooperative partners because of equal fitness concerns for one another (degree of relatedness)