Ever been called four-eyes? It may be hereditary!
This is Sandra Tsing Loh with the Loh Down on Science.
Some of our oldest known relatives might have had four eyes.
Xiangtong Lei from Yunnan University and team examined the best-preserved ancient fish fossils. These fish had two extra sensing organs on their heads.
At first, researchers thought they helped the fish smell or sense light – but not see.
They used scanning and chemical imaging techniques to verify this.
The surprise? These extra organs likely had cells that were organized like pixels on a screen. Together, they could form images – just like the cells in our retinas.
So being called “four eyes”? That’s ancient history.
Reference: Lei, X., Zhang, S., Cong, P. et al. Four camera-type eyes in the earliest vertebrates from the Cambrian Period. Nature 650, 150–155 (2026). https://doi.org/10.1038/s41586-025-09966-0