Monkeys 'learn to eat soil to cope with junk food'

Monkeys 'learn to eat soil to cope with junk food'1 hour agoShareSaveAdd as preferred on GoogleGibraltar Macaques ProjectMacaques on Gibraltar eat tourist food rich in sugar, salt and dairyMonkeys living on Gibraltar have learned that swallowing soil can quell upset stomachs caused by eating snacks offered or stolen from tourists, research suggests.Food such as chocolate bars, crisps and ice cream have negative digestive effects for the macaques but are "as delicious for them" as they are for humans, according to a Cambridge University study.Eating soil may allow the primates to keep eating junk food by helping to line the gut to prevent irritation from too much sugar and fat, research indicates."The emergence of this behaviour in macaques is both a functional and cultural one, like nutcracking in chimps, except it is driven entirely by proximity to humans," said biological anthropologist Dr Sylvain Lemoine.Gibraltar Macaques ProjectThe monkeys may love ice-cream - but their stomachs don'tSome of the Rock's 230 monkeys in frequent contact with tourists were observed to eat more dirt, and dirt-eating rates were seen to be higher during peak holiday season.The researchers think the behaviour is likely to have been learned socially as different troops of monkeys have preferences for certain types of soil.Scientists believe the dirt also provides bacteria and minerals absent from junk food - which is completely unlike the monkeys' typical diet of herbs, leaves, seeds and the occasional insect.Gibraltar Macaques ProjectMacaques were observed gathering soil to eat"We think the macaques started eating soil to buffer their digestive system against the high energy, low fibre nature of these snacks and junk foods, which have been shown to cause gastric upsets in some primates," added Lemoine."The consumed soil acts as a barrier in the digestive tract, limiting absorption of harmful compounds."He said tourist foo...