Hanging out with dad brings benefits for the kids. Credit: Susan C. Alberts

It's not just humans who benefit from having a father figure around; the longer a yellow baboon?s dad sticks around, the better it does, new research shows.

The discovery shows that there?s more to male baboon life than sex and fighting, says Jeanne Altmann of Princeton University in New Jersey. ?We haven?t given males due credit for the subtlety and complexity of their behaviour,? she says.

Altmann and her colleagues studied yellow baboons (Papio cynocephalus) living in Amboseli National Park in Kenya, near the base of Mount Kilimanjaro. They report their results in Proceedings of the National Academy of Sciences1.

The animals live in groups averaging 40 individuals. Females are generally loyal to the group they were born in, but males disperse. Some move regularly from group to group, others stay in the same group for several years.

The researchers looked at 118 baboons born between 1982 and 2002, of which 40 were male. Testing DNA from faeces revealed the identity of each youngster?s father.

The team had previously shown that adult males intercede in fights on their offsprings' behalf2. But the consequences of this weren?t clear. It has been suggested that males help out their young to show off their own qualities as a mate, rather than to specifically protect the juveniles. The new results, however, suggest that there is something in it for the kids, too.

They grow up so quickly

It turned out that the longer a father spent in his offspring's group, the earlier that offspring became sexually mature. Maturing early shows that a baboon is healthy and growing fast, and gives the animal?s reproductive chances a big boost.

?Males create a zone of protection around their offspring,? explains Altmann. She suggests that by intervening in and generally deterring fights, a male baboon can have less stressed offspring with more time for feeding.

Female baboons benefited regardless of their father?s status, although the effect on them was relatively small. The bigger effect was seen with male offspring, who were only helped if they had a high-ranking father. Males are victim to more aggression, so are harder to protect, but benefit more from effective protection. ?Young males are targeted by other males ? there?s a huge pressure to protect your son,? says primatologist Phyllis Lee at the University of Stirling, UK.

The key question, says Guy Norton of Anglia Ruskin University in Cambridge, UK, who works on another long-term study of yellow baboons, based in Tanzania, is whether paternal care improves a baboon?s chances of surviving to breed. Altmann does not yet have data on this point, but she plans to address it in the future.

Negligent dads

Fewer than 10% of mammalian species have been documented exhibiting male paternal care. It?s thought that this is partly due to the difficulty a male may have in telling which offspring are his. It?s not known how male yellow baboons achieve this ? they might remember mating with the mother when she was most fertile, or see or smell a family resemblance, or some combination of the two.

Some male baboons form long-term partnerships with females, and provide a lot of childcare, says Norton. ?You see infants bouncing around them like fleas,? he says. Norton thinks that such males might be older animals, who are no longer able to fight for mates, which therefore focus on protecting the offspring they have.

In some species, parental presence delays the onset of puberty. This is true of human girls; it?s thought that the delay might be a way of avoiding inbreeding. In baboons this would not be likely; more than 80% of fathers had died or moved on by the time the offspring in the study group began reproducing.