From ABC Science, 8 November 2016:
You may struggle to see your computer screen as you get older, but we are not the only primates to suffer from declining vision as we age.
The discovery, published today in the journal Current Biology, challenges the idea that we live longer after the end of our reproductive lives than other primates because we are physically more robust.
Long-sightedness, or presbyopia, is caused by the gradual hardening of the lens and weakening of the muscles around it, which makes it more difficult to focus on objects up close.
While studying a group of bonobos in Wamba, Congo, a team of researchers noticed the strange grooming behaviours of the older members of the troop.
The oldest male bonobo — Ten — had to stretch his arm out to groom another bonobo called Jeudi. Then, when he found something, he would come back in close to remove it with his mouth. Read more.