The largest of all the Colobus, measure around 45-72 cm without the tail and weight between 5-14 kilos. They are diurnal, they live in groups up to 15 members.
Colobus ar polygamous, there is a dominant male and 3 or 4 reproductive females. Females stay in the group all their life and they raise the offpring together. Colobus guereza breed every 2 years and the gestation period last about 6 months. They spend most of the time on the trees, the thumb is absent as an adaptation to this way of life.
The diet is mainly folivore, the stomach divided in 2 regions; the upper part is necessary for fermentationos foliage by anaerobic bacteria. The average os lifespan is 20 years.