Complex animals living millions of years before the #Cambrian Explosion revealed by seabed tracks https://phys.org/news/2025-07-complex-animals-millions-years-cambrian.html

"from ~550 million years ago, there are simple tracks with abrupt turns. These have been made by simple #animals with short, round bodies and limited senses... About 545 million years ago, smoother tracks with fewer abrupt turns appeared... short animals were gaining greater control of movement... At about the same time, smooth trails similar to those of worms appear"