Post by Barry on Nov 27, 2009 17:23:47 GMT
Grandmother monkeys care for baby
From the BBC at news.bbc.co.uk/earth/hi/earth_news/newsid_8370000/8370743.stm
Leaving aside my utter dismay at the BBC, of all organisations, misspelling 'dependent' (what is the world coming to?), I found this pretty interesting. Selfish genes, evolutionary psychology and all that...
From the BBC at news.bbc.co.uk/earth/hi/earth_news/newsid_8370000/8370743.stm
Two grandmother monkeys have been seen intervening to raise their own grandchildren, providing essential care including suckling the young.
The scientists who witnessed the behaviour say it is the first unambiguous example of such behaviour shown by a non-human primate.
The observations were made in a free-ranging group of Japanese macaques living in Katsuyama, Japan.
...
The behaviour of the two elder monkeys offers support to an idea called the 'grandmother hypothesis'.
"It is an idea that post-reproductive grandmothers can play an important role in the survival of their grandchildren, although they cannot produce their own offspring," explains Dr Nakamichi.
By doing so, he says, females can improve the chances that their own genes will be passed on down the generations.
The idea helps explain why mammals such as monkeys can live well beyond reproductive age, as by doing so, they can continue to promote the survival of their relations.
However, definitive evidence for the hypothesis has been difficult to obtain.
Numerous studies have shown that monkeys such as vervets, Japanese macaques and langurs will form close relationships with their grandchildren, investing time in them and occasionally helping to protect them.
Yet other studies on Japanese macaques, baboons and titi monkeys, for example, do not show that the presence of grandparents improves an infant's survival.
In other social mammals such as elephants, grandmothers may also occasionally help out with grandchildren.
But usually the grandmother has more offspring of her own, and does not provide essential, life-saving care.
"To our knowledge, there have been no reported cases in which, instead of a mother, a grandmother without dependant offspring has continuously provided essential care for the survival of her dependant grandchild, which is in accordance with the grandmother hypothesis," Dr Nakamichi and colleagues write in the journal Primates.
The scientists who witnessed the behaviour say it is the first unambiguous example of such behaviour shown by a non-human primate.
The observations were made in a free-ranging group of Japanese macaques living in Katsuyama, Japan.
...
The behaviour of the two elder monkeys offers support to an idea called the 'grandmother hypothesis'.
"It is an idea that post-reproductive grandmothers can play an important role in the survival of their grandchildren, although they cannot produce their own offspring," explains Dr Nakamichi.
By doing so, he says, females can improve the chances that their own genes will be passed on down the generations.
The idea helps explain why mammals such as monkeys can live well beyond reproductive age, as by doing so, they can continue to promote the survival of their relations.
However, definitive evidence for the hypothesis has been difficult to obtain.
Numerous studies have shown that monkeys such as vervets, Japanese macaques and langurs will form close relationships with their grandchildren, investing time in them and occasionally helping to protect them.
Yet other studies on Japanese macaques, baboons and titi monkeys, for example, do not show that the presence of grandparents improves an infant's survival.
In other social mammals such as elephants, grandmothers may also occasionally help out with grandchildren.
But usually the grandmother has more offspring of her own, and does not provide essential, life-saving care.
"To our knowledge, there have been no reported cases in which, instead of a mother, a grandmother without dependant offspring has continuously provided essential care for the survival of her dependant grandchild, which is in accordance with the grandmother hypothesis," Dr Nakamichi and colleagues write in the journal Primates.
Leaving aside my utter dismay at the BBC, of all organisations, misspelling 'dependent' (what is the world coming to?), I found this pretty interesting. Selfish genes, evolutionary psychology and all that...
