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David Attenborough: In this tree there is one of the most extraordinary plant predators. It’s one animal that I don’t need to sneak up on … Boo! This extraordinary creature is half-blind, half-deaf and this is just about as fast as it can move. That’s what’s going to happen to you if you live on nothing but leaves!
It’s a sloth. It’s not exactly an enthusiastic leaf eater - a couple of half-hearted chews and the leaves go straight down to its stomach. Leaves however are not easily digested. The sloth’s technique is to give them time. Then eventually this mobile compost heap pulls itself together and starts on a long and dangerous journey. This is a very unusual sight, a sloth in a hurry! It wants to defecate. And the only place it’s happy doing that, oddly enough, is down on the ground. It only does it about once a week but why does it come down to the ground to do it? And why does it nearly always choose to do so in exactly the same place? Whatever the reason it must be very important, for a sloth on the ground is almost helpless. Any predator can attack it and it doesn’t have the speed to escape. Why it comes down in this way is a mystery … nobody knows! Now he’s finished and back he goes, up to the safety of the canopy.
Leaves are not very nutritious. The sloth’s way of compensating for all that is not to eat more but to do less. Its claws hook over the branches so that the sloth can hang without any effort of its muscles which have been reduced to thin ribbons, and to save energy it spends most of its time hanging around half asleep in the treetops. So with very little muscle and a reaction time only a quarter as fast as ours, how does a sloth’s day compare with our day?
In the time it takes me to write a few letters, the sloth just about manages to groom itself. While we have our lunch, the sloth nibbles a few leaves and then as we film a sequence for the series ... it’s time for another nap.
What did you think of the sloth? Which is your favourite animal?