Helmetia expansa was found to have walking legs and molting behavior, changing assumptions about its mobility and growth. For ...

A hunter dating back more than half a billion years has been discovered in Canada. Mosura fentoni was a trailblazer for modern arthropods, developing adaptations that some crustaceans and arachnids re ...

A recent study shows that marine oxygen levels were crucial to the evolution of early Paleozoic trilobite body size, suggesting that oxygen may have influenced the evolution of other animals' body ...

Its mouth was a tooth-ringed circle, a bizarre structure shared with other radiodonts, capable of crushing soft-bodied animals like trilobites or worms. Midway down its body were wide, undulating ...