 In weight, the male is much larger than the female, with the average adult weighing 7 to 10 kg, while females weigh on average 4.5 to 6 kg.It is thought to be a frugivore-folivore in diet.Some published reports indicated that Hamlyn's Monkey lives in small groups, of ten members or less, with one male and multiple females, with no data to show them occurring in monogamous groups.