Its function is to absorb water and salts from undigested food. It has a muscular wall that can knead the contents to speed up absorption.
The cecum is present in mammals, birds and some reptiles. Herbivores have a larger cecum than humans, and exclusive carnivores have a smaller cecum or none at all.
The appendix is a branch of the cecum. Like the appendix, the cecum (from the Latin caecus meaning blind) was once believed to have no function.