Early humans had long jaws that resulted in an unkempt chin. Today, the jaws are smaller in size and have the shape of a chin, which is one of the factors of beauty in modern humans.
About seven million years ago, our early ancestors had very small and long jaws. Their tusks were long and pointed. The teeth were also in two parallel rows. The jaws and teeth of our ancestors were similar to those of modern chimpanzees, and the teeth were oblong or U-shaped in the jaw. There was a diastasis or gap next to each of the canine teeth. These gaps were the spaces in which the large canines could fit when the jaw was closed. In the upper jaw, the gap was in front of the canine and in the lower jaw, behind the canine.
About 5.5 million years ago, the canines began to disappear. Research shows that two million years after the disappearance process, the teeth began to line up from back to front.
About 1.8 million years ago, like modern humans, the canines of our ancestors became comparatively shorter and flatter, and their jaws became shorter. This position made the face more vertical and forced the lateral rows of teeth to form a circular arc.
