A lot has happened for modern humans to get to this point. We lost most of our hair, learned how to make tools, established civilizations, sent a person to the Moon, and invented artificial intelligence. Whew! With all of these changes, our bodies have changed, too. It’s only taken us about six million years.
It all comes back to one key idea: evolution.
In 1859, Charles Darwin published his book On the Origin of Species, in which he explained his theory of evolution. He described the process of “descent with modification,” where physical parts—and even behaviors—of animals may change over multiple generations due to natural selection. If certain traits—such as sharp teeth or thick fur—helped the animal survive in the wild, then these favorable traits would be “selected for” and passed down to the next generation. Then that generation would pass them on. And so on.
And while favorable traits are passed on, other. This word comes from the Latin , or “footprint.” These vestiges are our body’s evolutionary leftovers.
