Monkeys, like humans, overeat. Monkeys gorge themselves on low protein fruit. Extremely large quantities are ingested which could lead to an increase in body fat. Food intake for monkeys is tied to the level of protein in food. If food has a high protein level they will eat less of it before feeling full.
Shoots and leaves have a high protein level. So they eat less of these to obtain their daily intake of 12 grams of protein. The reason that eating fruit does not make them fat is that it takes a lot of energy to obtain the fruit.
In Western countries we seek high carbohydrate food because we are trying to satisfy our craving for protein. The conclusion has been reached by scientists that human obesity began 40,000 years ago when people substituted meat with crude bread made out of wild grain. Humans have become fatter as easier ways of harvesting grains have developed.
http://www.adventure--australia.blogspot.com/http://www.tysaustralia.blogspot.com/
http://www.feeds.feedburner.com/AdventureAustralia
http://www.technorati.com/blogs/
http://adventure--australia.blogspot.com
Evolution