How arthropods got their legs

Fossils show flaps that fused to make modern limbs

ancient arthropod

FLAPPING AROUND  A newly discovered ancient arthropod had two rows of flaps that later melded into limbs like those sported by lobsters, horseshoe crabs, and other relatives alive today.

Marianne Collins/ArtofFact

Newly discovered fossils fill a gap in scientists’ knowledge of how arthropods evolved their legs.