Young bonobos console their fellow apes with hugs and sex, say scientists.
Although bonobos are known as the “empathic” apes, researchers previously thought that comforting behaviour was too complex for juveniles to grasp.
But studies at the Lola Ya Bonobo sanctuary in DR Congo, revealed that the youngsters often consoled the losers of social squabbles.
Researchers also found that apes raised by their mothers were more likely to offer comfort than orphans.
The results are published in the journal PLoS One.
Dr Zanna Clay, from Emory University in Atlanta, US undertook the study at the centre, near Kinshasa. The sanctuary rehabilitates rescued bonobos and is the largest of its kind in the world.
“I’ve spent a long time observing bonobos over the years, and have often noticed how much juvenile bonobos approach victims to comfort them,” Dr Clay told BBC Nature.
“This is why I found it surprising that the ape literature has really only focussed on consolation in mature individuals, it hasn’t been really looked at before in juveniles.”
Bonobos are well known for their close relationships and peace-keeping behaviour, including sexual activity to help relieve tensions.
However, the process of consoling a distressed fellow ape following conflict was considered to be a complex behaviour, requiring sophisticated cognitive skills.
Scientists thought immature bonobos that do not have the experience of adult apes, would not be able to discern what the appropriate behaviour should be in these circumstances.
However, Dr Clay and colleagues observed bonobos of all ages making physical contact with the distressed victims of conflicts, offering a comforting embrace or sexual contact.
“In bonobos, comforting behaviours take numerous forms, which include embracing, touching, patting and a wide array of sexual contacts,” explained Dr Clay.
“Sexual behaviours are an especially important feature in comfort-giving and reconciliation in bonobos, while kissing – something observed in chimpanzees – is absent.”
Bonobos are known to scratch themselves when stressed but comforting contact diminished this scratching, according to the study.
A friend in need
The researchers found that young apes were, in fact, particularly sensitive toward others, challenging previous theories that suggested they lacked such empathy.
“This study highlights the fact that, similar to humans, sensitivity to the emotional states of others actually emerges very young in bonobos and may not require so much complex cognitive processing as has previously been assumed,” Dr Clay commented.
Instead, biologists suggest proximity may be the key factor in consolation behaviour.
During the study, Dr Clay noted that nearby bystanders were more likely to comfort distressed parties, as were close relatives and “friends”: unrelated animals that share close bonds within the group.
Analysis of the background of the apes also revealed that orphans were less likely to behave in this way than juveniles that had been raised by their mothers.
“We found a strong effect of rearing… which highlights the importance of early experiences on emotional and social development in non-human animals, something which needs more attention in future research,” said Dr Clay.
She suggested that comfort-giving could be a “hard-wired” response that becomes more sophisticated with age.
“The results from this study indicate that the comfort-giving behaviour may be based upon fairly simple mechanisms of ‘self-other discrimination’ that do not necessarily require a lot of advanced cognitive skills.
“Nevertheless, the fact that apes display this behaviour but monkeys do not, suggests that apes still possess special social abilities that monkeys lack.
“We’re doing some analyses now to look at how the nature of consolation changes with age, as while juveniles console victims, it may be different to the nature of consolation offered by adults.”
Credits: BBC Nature