Research published in Science Advances have now revealed a speculative shape for an ancient arthropod head. This comes after studying and extrapolating on juvenile subjects that may have a strong indication of what the adult head may have looked like.

Anthropleura, the ancient arthropod in question, was a centipede-like creature that lived in the Carboniferous period, or around 359 million years ago. Based on fossils found in the United States, Canada, and Scotland, adult Anthropleura could grow up to nine feet long and weigh around one hundred pounds. However, there had been debate surrounding the shape and construction of the creature’s head. This is because fossil records often contain merely the exoskeletons of adults, meaning they only contain the body and legs. 

Yet, researchers were able to find fully intact fossil specimens of juveniles they believe to either be the same species or one very similar to Anthropleura. Using CT scans, they were able to get a full picture of the fossil without breaking apart the fossil, which may have damaged precise details. This allowed them to create a head structure that could have reasonably existed on the creature. 

The head resembles that of a modern-day centipede. It is a bulbous oval shape, with two short antennae and a small mouth, which it used to eat its diet of bark and leaves. Despite the size of the Arthropleura, their construction suggests they were most likely decomposers. This strengthens its connection to the modern day millipede, who serves much of the same niche.

By studying Anthropleura, it’s possible to not only track the development of decomposers, but also the development of vital ecosystem functions as early biodiversity increased. As well, the use of CT imaging and juvenile extrapolation may allow future scientists to better understand not only Anthropleura but similarly aged species.