Here There Everywhere

An artist’s interpretation of what our earliest ancestor may have looked like. Illustration: S Conway Morris / Jian Han

An international team of scientists recently discovered what’s likely to be our oldest ancestor. And it turns out we had big mouths even back then!

This is an amazing discovery, first, because it’s really, really old — over 500 million years old. Usually when we talk about our evolution as humans we’re talking more like 4 million years , not over 400 million years.

This creature, called a saccorhytus, isn’t human-like on its own but it has some features that makes scientists believe that it’s the common ancestor that started a whole category of evolution that includes humans. The category is called deuterostomes and also includes other land and sea animals like starfish, sea urchins and rabbits to name a few.

This creature, big mouth and all, was actually tiny. It probably lived in the sea between grains of sand.

Fossils that old and that small are really rare to find and when scientists did discover them they looked more like a handful of rice. But when they looked at it under a special microscope they were surprised by what they saw.

The original finding was published in Nature  including the pictures of the microscope images and the fossils in rock.