The laid-back life of a sloth

The afternoon draws to a close. Night falls. He awakes.

He was curled up asleep, in the highest branches of a tree. Feeling the gnaw of hunger, he lifts his head and slowly reaches out to pull a branch towards him. He tears off a leaf with his rough lips and begins to chew. He eventually decides to move; he extends his long arms to grab a rather flimsy-looking branch but takes the time to make sure it is strong enough to take his weight. Now with all four limbs stretched in different directions, like a Tai Chi master, he shows great “quiet” strength by moving horizontally, supported by two fully extended limbs. He moves from tree to tree with ease.

Tips for camouflage

As is his habit, he swings back and forth while hanging from a branch, his back to the ground. Raining? No problem—there is a part in the fur on his belly ensuring that the water is whisked away efficiently. An ocelot—a large cat—passes by in the same tree but doesn’t notice, taking him for a termite nest against the trunk. Green algae grows in his fur, enhancing his camouflage . A myriad of tiny invertebrates call his luxuriant coat home, including many that feed on the algae. Tonight, he will have to climb down to the foot of this tree to empty his bowels, which he must do about once a week.

Marvellously adapted to tree life

Like the five other species of sloth, the two-toed sloth (Choloepus didactylus) is a wonder of adaptation to life in trees: long claws to hang from and to defend itself, surprising strength and agility, and near-perfect camouflage.Neither its sight nor its hearing is very good.Instead, it relies on its sense of smell to find the trees whose leaves, blooms and fruit it likes most. It’s not averse to the odd insect, egg or chick as an occasional snack.

As its diet is not very high in energy, the sloth is an expert in energy conservation: its body temperature varies between 30 and 34⁰C, depending on the ambient temperature. Other mammalshave higher, more stable internal temperatures: around 37⁰C, like humans. It moves only when necessary to fulfil its basic needs and rests often. Perfectly integrated into the nocturnal life of the tropical rainforest of Latin America, its fate is bound to the condition of its habitat.

So, how slothful are sloths?