Hominids learnt how
to throw around two million years ago, a skill which heavily influences much of
what we are today.
You can go and look at any sport stadium across the world and you'll be able to witness humans incredible ability to throw. Especially when compared to our relatives the chimpanzees who can only throw at around 20mph against our speedy 90mph. This has lead many people to question how this ability evolved, and more importantly, why.
Recent investigations into the fossils of our earliest
ancestors show that Homo erectus underwent
anatomical changes during its evolution which gave it its ability to throw. It
might not seem much to us now, in a world where we mainly throw around balls or
our mobile phones, but two million years ago being able to throw would have
been the difference between life or death.
To try and understand this evolutionary development,
researchers first looked at how humans throw today. They did this by recording
a sample of athletes using motion capture cameras, with particular focus on
their shoulders. This showed that the many ligaments and tendons that are
involved in the movement of the shoulder are able to store a large amount of
elastic energy, which can be released and used to force a projectile through the air. It would have been
this ability to store elastic energy that would have put Homo erectus apart from Homo
habilis and allowed it to throw at great speed.
Unlike other animals with large claws and teeth, humans have
no natural weapons, and so required other methods of attack and defence. The
ability to throw would have been an important step in our evolution, as it
allowed us to defend ourselves against predators, as well as become predators ourselves. This change in diet to containing
energy rich meat would have in turn also allowed for further changes in our
biology, giving us the much larger bodies and brains that we have today.
It has also been suggested that this change in diet led to
the division in labour between hunter and gatherers. This would have promoted a
much more complex social hierarchy between the individuals of the group, a hierarchy that can still be seen in us humans today.
This hunting behaviour would have also been a deciding
factor in our migration into new environments, which, without the ability to
hunt, would not have previously been able to sustain our vegetarian lifestyles.
These are all big parts of what makes us human, and just goes to
show how one small adaptation could influence an entire organism’s future.
However, as is always the case with this kind of research,
there are those who dispute the above findings. Susan Larson, whose work also
focuses on shoulder anatomies has suggested that the above conclusions may have
been drawn from an over interpretation of fossil evidence. She suggests that Homo erectus was not necessarily a very
good thrower when compared with modern day human athletes, but rather a change
in their anatomy gave them a much larger range of movements which would have
allowed them to manipulate their environment more successfully.
There is always going to be dispute in this type of
research, as very little is based on good solid fact, with most theories being
developed and built up from one single piece of information.
However, what cannot be disputed is the importance of our
ability to throw. Without being able to throw weapons we would not have been
able to hunt, which would have prevented us evolving our large bodies and
enormous brains, as well as stopping us from venturing into new environments
and developing our complex social hierarchy.
So, next time you’re throwing something around, whether it
be a ball or an inanimate object that’s annoyed you, think about the millions
of years of evolution that’s gone into it, and try and appreciate it that
little bit more.