Who would have thought that regular teeth would one day help us understand our evolution through history? A team of witty researchers have determined that the inhibitory cascade is linked to the evolution of prehistoric teeth.
Scientists have been trying to explain the evolution of teeth for many years now, and it appears they finally found a lead. The explanation lies in a general evolutionary trend, and is not necessarily limited to us humans.
It all starts with wisdom teeth. Yes, those wisdom teeth that annoy us so much and bring us pain both when they appear and when we have to extract them. In spite of all this suffering, they tend to be underdeveloped and quite small in humans. Also known as third molars, wisdom teeth used to be much larger in species that precede our own. Back in the time, these teeth could chew up from two to four times more surface than they do in the present day.
Until now, it was largely believed that the shrink in size was caused by a change of lifestyle such as culture, dietary habits or intermingling. However, the whole answer to the dilemma is actually much simpler than we have imagined it to be.
The latest study on the matter has reached the conclusion that inhibitory cascade is to blame for the changing process. So what did the researchers do exactly?
They started from the fact that teeth have already given us a lot of information on our ancestors. After a close analysis of both animal and human teeth, the scientists discovered that neither did anything truly special that changed them so much in time.
It appears that the modifications were suffered by all mammals, and not just humans, and these were due to the inhibitory cascade. The inhibitory cascade is one of the molar evolution hypotheses, and explains the existence of a balance between the mesenchymal activators and the molar-derived inhibitors. This balance is the one that sets the size of the posterior molar, which in turn determines the size of its neighbor and so on.
In the end, it seems all our teeth are influenced by one another, and there was no special event that triggered these changes. In this way it only seems natural that the last teeth in the row, the wisdom teeth, are the last ones to develop and the last to change. However, it is quite ironic how the latest teeth can influence the others, even if they had developed years before.
Image Source: zmescience.com