This episode of the InsideNATURE podcast is all about sloths; perhaps the strangest group of creatures evolution has ever produced. While other species get ahead by being the fastest, the biggest or the strongest, sloths do everything as slowly as possible, using the least amount of energy and remaining largely unnoticed. But don’t be deceived by their low-key lifestyle. Sloths have been around millions of years, much longer than humankind, so they must be doing something right! To guide us through the weird and woolly world of sloths, we got in touch with biologist Rebecca Cliffe. Rebecca’s research focuses on sloth conservation and she has taken an innovative approach--utilizing tiny sloth "backpacks"--to study the ins and outs of their daily life.