A giant sloth, was the image which came to Kirk's mind.

Notable among these are the giant sloth and the horse.

This was the first reported find of a giant ground sloth in the United States.

There was the giant ground sloth, which sometimes lumbered around on two legs.

Later the bones were positively identified as that of a giant ground sloth.

These were home to creatures like mammoths and giant ground sloths.

There is nothing alive today that is anything like a giant ground sloth.

There were fossils of such giant sloths on Earth.

One group was the giant ground sloths, such as the megalonychid Megalonyx.

The specific name indicates a resemblance to Megatherium, the giant ground sloth.