As for hearing, the sloth is not so much deaf as uninterested in sound.

Why it should look about is uncertain since the sloth sees everything in a Magoo-like blur. If you come upon a sleeping three-toed sloth in the wild, two or three nudges should suffice to awaken it it will then look sleepily in every direction but yours. On a scale of 2 to 10, where 2 represents unusual dullness and 10 extreme acuity, Beebe (1926) gave the sloth's senses of taste, touch, sight and hearing a rating of 2, and its sense of smell a rating of 3. The three-toed sloth is not well informed about the outside world. Unmotivated, it covers four to five metres in an hour. On the ground, it crawls to its next tree at the rate of 250 metres an hour, when motivated, which is 440 times slower than a motivated cheetah. It moves along the bough of a tree in its characteristic upside-down position at the speed of roughly 400 metres an hour. The sloth is at its busiest at sunset, using the word busy here in a most relaxed sense. We found them still in place late the next morning, the water of the dishes swarming with insects. Our team tested the sleep habits of five wild three-toed sloths by placing on their heads, in the early evening after they had fallen asleep, bright red plastic dishes filled with water. It sleeps or rests on average twenty hours a day. I had the great luck one summer of studying the three-toed sloth in situ in the equatorial jungles of Brazil. There are two-toed sloths and there are three-toed sloths, the case being determined by the forepaws of the animals, since all sloths have three claws on their hind paws. I chose the sloth because its demeanour-calm, quiet and introspective-did something to soothe my shattered self. My zoology thesis was a functional analysis of the thyroid gland of the three-toed sloth.

My fourth-year thesis for religious studies concerned certain aspects of the cosmogony theory of Isaac Luria, the great sixteenth-century Kabbalist from Safed. My majors were religious studies and zoology. After one year of high school, I attended the University of Toronto and took a double-major Bachelor's degree. I have remained a faithful Hindu, Christian and Muslim. Academic study and the steady, mindful practice of religion slowly brought me back to life.

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