BONOBO BIFOCALS
As we age, our eyesight naturally deteriorates and corneal astigmatism worsens, typically after the age of 50, and that applies to other primates, too. The eyesight of humankind’s closest relative, the bonobo (Pan paniscus), becomes increasingly farsighted as they age. In 2016, researchers studied bonobos grooming members of their troop. What they discovered is that bonobos under the age of 30 looked into their grooming partners’ fur from around ten centimetres. However, by the age of 45 that eyesight distance had gradually increased to around 40 centimetres, suggesting the older apes were farsighted.