A recent study by scientists at Monash University in Australia suggests that changes in human teeth can explain a lot about human evolution.
Researchers think these changes can be much simple than previously thought and can predict the sizes of the missing teeth from hominin fossils.
There is a huge different between modern humans’ set of teeth and the hominin species’, particularly in the wisdom teeth. As our ancestor needed to chew a lot more than we currently need to, it seems interesting that we still grow wisdom teeth despite dentists are regularly taking them out.
According to the study, the evolutionary process made our wisdom teeth much smaller than the hominins’, and this process began with the appearance of the first Homo. The process is known as the inhibitory cascade, which is a general rule that decides the size of teeth by comparing them to the ones next to them. It affected the evolution of all our teeth and especially, our wisdom teeth.
Researchers used to believe that the changes in the size of the wisdom teeth were a result of cultural and behavioral changes, but fossil evidence shows that its size decreased because of biology reasons and began decreasing in modern times.
Early humans’ first tools were their teeth. They hunted and ate their food by the use of much sharper teeth. But they began to create new tools out of rocks and bones and the inhibitory cascade debuted on the spectacle.
Researchers were able to find that the inhibitory cascade was the one that affected the evolution of our teeth because they spent decades analyzing hominins fossils and 3D reconstructed fossil teeth.
Data gathered was compared to the australopiths and the genus homo, which are two species of the hominins. The comparison showed that both species were affected by the inhibitory cascade and only had a few differences.
Alistair Evans, an evolutionary biologist who is in charge of the research said that the study will help future researchers to do better analysis of our ancestors’ lifestyles.
He added that now that they know how the inhibitory cascade works, they will be able to better understand the data gathered and future fossils, besides of being very useful for anthropologists, archaeologists and evolutionary biologists to build better computer models of a head of a fossil based only on a few teeth.