Mate choice Flashcards
Female mate choice is a form of intra-sexual selection. True or false?
False, it is INTER-sexual selection
There are two kinds of female choice. What are they?
- Direct female choice
2. Indirect female choice
What is direct female choice based on?
Male morphology; fitness-dependent traits
Give 2 examples of attractive male traits.
- Dominance rank
2. Colouration
Colouration is particularly important to which species of primate?
Mandrills (closely related to baboons)
Mandrills are profoundly sexually dimorphic. What colours do males have on their faces, rump and genitalia?
Red, blue and violet
What is interesting about direct female choice in mandrills, which trait is most important to them? Who found this?
Colour is more important than dominance rank
Setchell, 2004
Setchell, 2004;
How do we know female mandrills prefer colour to rank? Give 3 examples.
- Colourful males are groomed most often
- Colourful males have the most successful mounts
- If a colourful male falls in rank, female attraction towards him does not change
Setchell, 2004
If a colourful male mandrill fell in rank, females continue to try and mate with him. Will he accept their solicitations? What does this suggest?
No, suggesting the dominance hierarchy is very important for male behaviour
What is indirect female choice based on?
Female morphology; ano-genital swellings
‘Any behaviour that restricts the chance of mating with certain individuals is said to be mate choice’. How does this relate to indirect female choice?
Although they do not actively discriminate, indirect female choice excludes some males from the mating pool
How does indirect female choice work?
It sets up competition between males. Whoever wins is seen as the better competitor and preferentially mated with
Which group have the largest sexual swelling of all primates?
Baboons
Why might mandrills rely more heavily on colouration than dominance rank for direct female choice?
Mandrills live in huge groups of up to 600 individuals, the composition of which is transient as individuals join and leave. Females do not always know the rank of a male, colour is a more reliable indicator of quality
When do females display sexual swellings?
In the periovulatory period
Highman et al., 2008;
What causes sexual swellings?
Hormones
What kind of information do sexual swellings convey?
Fertility information
Size and colour of swellings are the same in all females. True or false?
False, they vary between individuals and relate to the fertility of the female
Highman et al., 2008;
What does the size of the swelling correlate to? Which hormones are involved and what do they do?
Ovulation; oestrogen stimulates swelling and progesterone inhibits it, conveying messages about which stage of ovulation a female is in
What does swelling colour correlate to?
Parity
What is parity?
The number of times a female has given birth
In baboons:
Sexual swellings advertise female quality to males. Therefore females with the biggest swellings are the highest quality. True or false?
False:
It was found that swelling size increases with cycle number when it is unbroken by conception (Highman et al., 2008)
Why do males prefer older females?
They are more experienced mothers and it is more likely that their babies will survive.
Swellings are more likely to be graded signals. What does this mean?
Based on numerous variables, like cycle number and individual variation in ovulation and fertility.