The Evolution of Human Teeth

Did you know that throughout the course of human evolution, our mouths and dental structures have changed a great deal?

Understanding our teeth means we have to consider the specific function(s) of each type of tooth in its current state, as each plays a vital role in the digestion process. Let’s explore how some of our teeth currently function and examine how they have changed over time. Who knows – it might lead to some insight into your own dental situation! 🙂


Your incisors are the central four teeth that are positioned at the front of your upper and lower jaws. Maybe you’ve noticed on your own time in front of the mirror that these teeth in particular are thin and flat, but you may not know that they are also sharper and stronger than most of the other teeth in your mouth!

Incisors have not always been present in the human evolutionary chain. In fact, they developed in a way that can be correlated with when humans began to consume the meat of other animals. The main purpose of these teeth is to tear away the meat or flesh from other animals and bring it into the mouth to initialize the digestive process.


Canines flank the incisors – one each on the left and right sides, in both the top and bottom rows of your teeth. While the incisors tear into meat, the canines clamp down on it – keeping the meat locked into the oral cavity. Feel yours now – pretty sharp right?

Over the course of time, the exact size & shape of canines have varied depending on the source of food humans and their predecessors consumed, mostly either plants, meat from other animals, or both.


Sometimes also referred to as pre-molars, our bicuspids are the next teeth in the lineup, and they are short and flat with a bit of sharpness to them for one of two purposes: the actual processing and breaking down of foods, or to move food along to the back of the mouth.

It’s hypothesized that bicuspids might have been the select few teeth for some of our ancestors who were already eating meat. For these ancestors, a good amount of chewing would occur here as the food is passed on for further processing.


In the very back of your mouth are your molars, appearing on both left and right sides in the upper and lower jaw. Your molars are flat and wide, which makes them a prime location to grind up and further process your food. This is where most modern humans end up chewing their food and it’s the last step before food moves to the next stage of digestion.

The molars are permanent teeth from the moment they emerge in one’s mouth – they do not emerge as baby teeth – and they’re held in very tightly by the roots of their teeth. Molars are stronger teeth that served the purpose of breaking down food thoroughly. This was especially the case for plant life, as their cellular composition is stronger and harder to break down.

As most have found out, our third molars – aka wisdom teeth – no longer can fit in our mouths properly. Why? Modern humans chew less than our ancestors because our diet is much softer now than it was then. The more one chews, the more the growth of the jaw is stimulated. (Our predecessors must have been eating a lot of interesting stuff!) So though all three molars fit well in our jaws before, they no longer do. Isn’t that interesting?


When considering the historical functions of our teeth compared to how they function now, it’s clear that our diets have heavily influenced the development of our pearly whites. Modern human diets have changed dramatically when compared to our ancestors. It will be interesting to see how our teeth develop into the future.

What do you think will happen as our teeth continue to evolve? Tell us at your next appointment – schedule one today!