WASHINGTON (AFP) - Just like humans who rely on reading glasses when they age, older wild bonobo apes can benefit from magnifying eyewear, new research shows.
Bonobos - among the closest primate relatives to humans - begin showing symptoms of far-sightedness when they reach 40 years old, according to research recently published in the journal Current Biology.
"We were surprised that the pattern found in bonobos is strikingly similar to the pattern in modern humans," Mr Heungjin Ryu of Kyoto University's Primate Research Institute said.
Researchers using digital photographs found the range at which the primates preen each other increases exponentially with age, implying that their eyesight worsens over time.
Just like elderly people holding newspapers at arm's length, ageing bonobos stand back to better spot insects and twigs on their friends.
"The results we found were very surprising even for us," Mr Ryu said. "When I started to collect data, I did not expect that age could be such a strong predictor of long-sightedness." The findings suggest that difficulty seeing up-close is not necessarily a modern affliction resulting from too much screen time or reading, but a genetically deep-rooted effect of ageing.
Aging patterns in humans and bonobos do vary in other ways, however. As people grow older, their ears get longer, while bonobos' remain unchanged.