There
are many matrilineal mammal groups from lions to orcas to chimpanzees
(I think). Are there any cases where the males stay with the family
group as they mature and females that enter breeding age are forced out,
or does the nature of mammalian child rearing make this highly unlikely
due to the need to nurse?
The answer:
Royals
and old moneyrs come to my mind. And stay in for good reasons. Humans in
general have very ancient formula of female juvenile dispersal, and the
most clear examples in western history and society are found in these
types of families.
Because we are talking about sex biased juvenile dispersal.
- Apart from humans, the animal that seems to fit better in your description is painted wolf (Lycaon pyctus). And I refer to them with a bit of surprise, I used to think that they are the canine mirror of hyenas, but this is wrong when it comes to sex ratios in packsis as biased as 3 males for every female, and males consistently remain in their natal pack while females disperse. It is very significative the fact that reproductive females are terrificly prolific, with an average of 10 puppies by litter.
Because we are talking about sex biased juvenile dispersal.
- Apart from humans, the animal that seems to fit better in your description is painted wolf (Lycaon pyctus). And I refer to them with a bit of surprise, I used to think that they are the canine mirror of hyenas, but this is wrong when it comes to sex ratios in packsis as biased as 3 males for every female, and males consistently remain in their natal pack while females disperse. It is very significative the fact that reproductive females are terrificly prolific, with an average of 10 puppies by litter.
- Many primates, like chimpanzees, gorillas and red colubuses.
Yes, chimpanzes practise female dispersal. It is bonobos the species
that opts for male dispersal. This doesn't mean that male dispersal is
absent, but that female dispersal is the general rule. (Humans have been
mentioned before).
- Although sex biased dispersal can be linked to social and philopatric mammals, there some other factors that can favour it, such as mortality costs of it and enviromental pressures.
Some lesser known examples, in which the sex ratio at dispersal is biased towards females: procyonidae (potus flavus), chiropetra (Saccopteryx bilineata) and Equidae (horses).
Although it is not required by your question it is interesting to tell that there can also be some type of bias in sex ratio at birth in mammals, that generally are an answer to ecological selective pressures. You can find interesting this question:
In what species of mammals males tend to outnumber females?. What could be the ecological reasons?
Interesting data in:
http://onlinelibrary.wile
- Although sex biased dispersal can be linked to social and philopatric mammals, there some other factors that can favour it, such as mortality costs of it and enviromental pressures.
Some lesser known examples, in which the sex ratio at dispersal is biased towards females: procyonidae (potus flavus), chiropetra (Saccopteryx bilineata) and Equidae (horses).
Although it is not required by your question it is interesting to tell that there can also be some type of bias in sex ratio at birth in mammals, that generally are an answer to ecological selective pressures. You can find interesting this question:
In what species of mammals males tend to outnumber females?. What could be the ecological reasons?
Interesting data in:
http://onlinelibrary.wile
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