It’s been ages since we’ve had Science together, but I’m happy to say that I’m feeling much better now and it is wonderful to see everyone again. I missed you all very much!
This week, in honor of the letter ‘O,’ we learned about opposable thumbs.
First, we looked at a cat’s paw.
Cats have retractable claws. We turned our hands into paws with claws and tried retracting them.
Then we looked at a bear’s paw
and contrasted it with the cat’s.
We learned that another name for fingers and toes is ‘digits.’ Cats have four digits on each foot. Bears have five.
We alsolooked at a person’s hand and compared it with the paws. We have five digits on each hand and foot.
It’s good to have an extra hand if you want to pat yourself on the head!
Next, we created a cat’s paw with child-sized digits. Cats have four digits. They are all next to each other. The claws are usually retracted.
Bears have five digits. They are also all next to each other. The claws are not retracted.
People have five digits, but one of them (the thumb) isn’t lined up with the others. It is separate from the rest.
In fact,it is opposite the others. That’s why the thumb can give the fingers high-fives!
(Bear’s digits can’t really do that without moving – but they can still try!)
That’s also why we can easily touch our thumb to each one of our fingers.
Because the thumb is opposite the fingers, it is called an ‘opposable’ thumb.
Some animalshave opposable digits. Here are some monkeys with opposable thumbs and big toes:
Gorillas have opposable thumbs and big toes, as do orangutans, and chimpanzees.
Note that gorillas, orangutans and chimpanzees are apes, not monkeys. Monkeys have tails. Apes do not.
When Curious George gets in trouble and starts running away and people are chasing him and yelling, "Stop that monkey! Stop that monkey!" he never stops. George does not have a tail. He’s an ape, not a monkey. Maybe that’s why he keeps on running.
Koalas have opposable big toes on their hind feet and TWO opposable thumbs on each front foot. That’s six opposable digits!
The best way to learn why opposable thumbs are important, is to not be able to use them for a while. We prepared to do several tasks without using our thumbs by putting Super-Scientific-Thumb-Immobilizers on our hands.
Then we tried putting snap-cubes together and writing our names with crayons — no thumbs allowed.
We took off the thumb-immobilizers, took the cubes apart and used the crayons some more. We were all extremely relieved when we were allowed to use our thumbs again!!
Now we know one reason that cats don’t color with crayons.
See you next week,