The river chut split from its ancestor the chut. It now has an amphibious lifestyle eating the blue palm shrubs that live in and on the banks of the river. It has grown to twice its ancestors size but has not changed much. Its ears are smaller since it has to keep water out of them. Their nostrils now seal water tight and their coloring has changed to mimic the river and the flora in it.
They live in social groups of up to 10 individuals with unrelated females and two or three males, usually related. The groups have a home territory along the river and the resident males defend it viciously. They are known as "beach masters".
Since they spend most of their time in the river females cannot have their babies stay in the pouch because they would drown. So for the 1st few months after both the females will stay on shore until the babies are too big for the pouch. Babies grow very fast and drink a lot of milk. They usually only have 1 to 2 babies when giving birth.