Sid, the central sloth in the “Ice Age” franchise, is slow of wit but swift in body, while “Zootopia” installed its sloth, Flash, as an unhurried employee of the Department of Mammal Vehicles.

these sloths were one of the strangest animals of the ice age. They weighed as much, or more, than the short-faced bear at 1 tonne and stood 3 metres tall, growing to the size of an ox.