500-million-year-old #fossil reveals how #starfish got their shape https://phys.org/news/2025-06-million-year-fossil-reveals-starfish.html

A new #Cambrian stem-group echinoderm reveals the #evolution of the anteroposterior axis: Stephanie Woodgate et al. https://www.cell.com/current-biology/fulltext/S0960-9822(25)00681-5

"The fossil, #Atlascystis acantha, is the oldest known #echinoderm with a bilateral body plan. It bridges the evolutionary gap between the closest living relatives of #echinoderms, all of which have bilateral symmetry, and the familiar five-armed forms alive today."