Take a look at your hands, what do you see? You have 5
fingers, one of them being a thumb. The thumb looks, moves, and preforms
different actions than your other fingers. Without our thumbs, there’s a huge
variety of tasks that we couldn’t preform! Let’s explore the importance of our
thumbs!
Our thumbs are opposable, meaning you can touch your thumb
to your other fingertips. Try and connect the fingertips of your pointer finger
and middle finger, could you get them to rest flat on each other? No, you couldn’t!
Our thumb is our only opposable finger. The opposable motion is needed for a
large variety of tasks, including forming a fist, wrapping our hands around
objects like tools or balls, or even eat with one hand! Human thumbs began to
evolve around 2 million years ago!
There are many animals in our world that don’t have thumbs! Horses,
cats and dogs, or any other animals with hooves or paws do not have opposable
thumbs. These animals can’t grab or pick things up. Primates, our closest
animal relatives, have thumbs that are very similar to humans! Animals use
their thumbs similarly to how we use them by climbing trees, gathering and
eating food, grooming themselves, and using tools! Opossum, pandas, koala bears, and even some
species of frogs have opposable thumbs. Though many other animals have thumbs,
humans can move their thumb further across their hand than any other animal!
Without our thumbs,
we would be unable to use our cell phones, grip a steering wheel, and brush our
hair! Our thumbs are amazing adaptations, making us and the other animals with
thumbs very special!
Test life without thumbs! Tape down your thumbs and see how
helpless you’d be without our special adaptation! Take the All Thumbs
Challenge, see the rules at:
https://sciencemadefun.net/downloads/If_Animals_Had_Thumbs.pdf
