Ground Sloth Evolution. At their earliest appearance in the fossil record the ground sloths were already distinct at the family level. Like its fellow megafauna mammals the giant ground sloth went extinct at the cusp of the last ice age about 10 000 years ago likely succumbing to a combination of predation by early humans the gradual erosion of its natural habitat and the loss of its accustomed sources of food.
Today sloths are all small tree climbing animals. The evolution of sloths is interesting because two and three toed sloths appear very closely related but it has recently been suggested that they have vastly different ancestors meaning that they evolved through convergent evolution. Sloths belong to the superorder xenarthra a group of placental mammals believed to have evolved in the continent of south america around 60 million years ago.
Like its fellow megafauna mammals the giant ground sloth went extinct at the cusp of the last ice age about 10 000 years ago likely succumbing to a combination of predation by early humans the gradual erosion of its natural habitat and the loss of its accustomed sources of food.
However new research published today in bmc evolutionary biology suggests this makes them the black sheep of the sloth family. Much ground sloth evolution took place during the late paleogene and neogene of south america while the continent was isolated. Recent evidence suggests it may have been a burrower. At their earliest appearance in the fossil record the ground sloths were already distinct at the family level.
