WATCH: Proof of
evolution that you can find on your own body
DO try this at home.
It might sound a little offensive, but your
body is a museum, full of ancient relics that no one really needs anymore. From
your wisdom teeth to that weird way some of us can wiggle our ears, so much of
how we ended up as humans reflects what our animal ancestors needed for
survival. As this video by Vox explains, these strange
remnants, that stuck around only because they're not 'costly' enough to have
disappeared across many millennia, only make sense within the framework of
evolution by natural selection.
Here's one you can see for yourself right now:
if you hold your arm out, and touch your thumb to your pinky, you'll probably
see a raised tendon in the middle of your wrist. Right? If you don't have that,
lucky you - you're among the 10-15 percent of humans on Earth who were born
without this prominent feature in one or both of their arms.
This tendon connects to the palmaris longus, a
muscle that most of us have, but there seems to be no real reason for it being
there. As the video explains, research has found that
the presence of this muscle in our forearms does not give us any more
discernible arm or grip strength than people born without the muscle. In fact,
it's so inconsequential, surgeons often remove it and use it for reconstructive
or plastic surgery procedures elsewhere on the body.
So why did we end up with such a useless
muscle? Scientists have found that, while palmaris longus is present in many
species of mammals today, it's most developed in those that use their forearms
to move around - such as lemurs and monkeys.
Here's another one: have you figured out how
to manipulate the three muscles around the base of your ear so you can wriggle
it ever-so-slightly? Good job - you're demonstrating how another evolutionary
remnant has transitioned from an essential piece of equipment for our animal
ancestors to a party trick no one cares about in humans.
Just like many nocturnal animals today - such
as rabbits, gazelles, and cats - rely on the wide range of angles their ears
can turn and face to better locate the origin of a sound, the creatures we've
evolved from would have used the same trick millions of years ago. And we
haven't completely lost all of the 'equipment' they would have used.
As
Vox points out, not only did humans retain three of the muscles
involved in ear movement, studies have shown that these muscles still respond
to sound. They don't respond strongly enough to make our ears move
anymore, but they appear to give it their best shot.
From goosebumps and tailbones, to that adorable thing babies do
when they grasp whatever you put in front of their tiny fingers, there are
plenty of other examples of weird things our bodies have that hint at the
abilities of our ancient ancestors. I'll let the
Vox video above explain those to you, but let's just say there's a
good reason for why you always get chills when you listen to Adele.