Secondary compounds and food selection by colobus monkeys

The feeding behaviour of black-and-white colobus monkeys, Colobus guereza, has been studied in the rain forest of Uganda. These animals, which are mainly leaf-eaters, are very selective in their choice of food. Only 32 of the over 60 species of tree in the study area were seen to be eaten and over two-thirds of the diet came from only five species, of which Celtis durandii was the most important. Analysis of food and non-food plants showed a strong inverse correlation between food choice by guerezas and the concentration of procyanidin tannins. There was less correlation with alkaloid content.