Orphaned chimpanzees are found to face lifelong setbacks, as mothers teach foraging and social skills, study reveals
- Orphaned male chimps have fewer offspring and are less competitive as adults
- Chimps stay with mothers until they’re teens but feed themselves by age 4 or 5
- Researchers think mothers continue to teach juveniles foraging and social skills
- A prolonged childhood may be why chimps have relatively larger brains
A new report suggests that chimpanzees who lose their mother can face lifelong setbacks.
Scientists studying chimps in Ivory Coast’s Taї National Park found that male infants who lost their mothers, even as juveniles, had fewer offspring and were less competitive as adults.
Chimpanzees are raised almost exclusively by their mothers and stay with them until they are teenagers, a rarity in the animal world.
The researchers believe that, even when offspring are old enough to take care of basic necessities themselves, their mothers are still teaching them advanced foraging techniques and social skills necessary to thrive.
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A new study suggests orphaned chimpanzees face lifelong setbacks, even if they were juveniles when they lost their mothers. Researchers believe chimps learn advanced foraging techniques and social skills well into their teen years
A team with the Taï Chimpanzee Project and the Max Planck Institute for Evolutionary Anthropology kept full demographic records and collected fecal samples to determine paternity on members of three distinct communities for more than 30 years.
They found that male orphans still failed to thrive even if they lost their mother when they were juveniles.
The team, whose work was published in Science Advances, believe mother chimps teach their young valuable lessons into adolescence.
They may know where to find the best food, said lead author Catherine Crockford, ‘and how to use tools to extract hidden and very nutritious foods, like insects, honey and nuts.’
Studying several communities of chimps in Ivory Coast’s Taї National Park for more than 30 years, the scientists found that male orphans had fewer offspring and were less competitive as adults
Access to more nutritious food may be why chimps and other great apes have relatively larger brains than other primates.
WHO’S SMARTER, A CHILD OR A CHIMP?
Most children surpass the intelligence levels of chimpanzees before they reach four years old.
A study conducted by Australian researchers in June 2017 tested children for foresight, which is said to distinguish humans from animals.
The experiment saw researchers drop a grape through the top of a vertical plastic Y-tube.
They then monitored the reactions of a child and chimpanzee in their efforts to grab the grape at the other end, before it hit the floor.
Because there were two possible ways the grape could exit the pipe, researchers looked at the strategies the children and chimpanzees used to predict where the grape would go.
The apes and the two-year-olds only covered a single hole with their hands when tested.
But by four years of age, the children had developed to a level where they knew how to forecast the outcome.
They covered the holes with both hands, catching whatever was dropped through every time.
‘Offspring gradually learn these skills through their infant and juvenile years,’ Crockford said.
‘We can speculate that one reason offspring continue to travel and feed close to their mothers every day until they are teenagers, is that watching their mothers helps them to learn.’
Co-author Roman Wittig speculates mothers might be passing on social skills rather than survival tips.
‘Again a bit like humans, chimpanzees live in a complex social world of alliances and competition. It might be that they learn through watching their mothers when to build alliances and when to fight.’
There is good news for orphaned chimps, though.
In January another study from the Planck Institute found more than a dozen orphaned chimpanzees in the Tai Forest had been adopted by unrelated members of their community.
Both males and females devoted large amounts of time and resources to protecting the young, seemingly in a show of chimpanzee altruism.
‘Some adoptions of orphans by unrelated adults lasted for years and imply extensive care towards the orphans,’ Planck Institute researcher Christophe Boesch told Live Science.
‘This includes being permanently associated with the orphan, waiting for it during travel, providing protection in conflicts and sharing food with the orphan.’
Boesch said he was particularly surprised to see males involved in rearing the adopted infants, since parenting is the purview of females.
‘Some of these adult males go really far in adopting a motherly role, carrying the baby on their back, sharing a nest, helping babies to climb trees, really caring a lot.’