Look To the Sky, Mr. Monkey

Weather-wise monkeys are first to the fruit
24 June 2006

TO SNAFFLE ripe fruit before the competition, grey-cheeked mangabeys keep their eye on the weather. Not only can the monkeys remember how to find the trees where their favourite figs were ripening, they can also monitor the weather and return just as the figs are ready.
Karline Janmaat at the University of St Andrews, UK, made the discovery after tracking a group of between 18 and 26 mangabeys (Lophocebus albigena johnstonii) for 120 days in the Kibale Forest of Uganda. She found that whenever individual monkeys tested the ripeness of figs by squeezing and smelling them, they were more likely to revisit the tree if the weather warmed, accelerating ripening (Current Biology, vol 16, p 1212).
"It's very competitive in the rainforest, so you would expect it would pay to be able to predict when fruit ripens so you can get there first," says Janmaat.