A half-billion-year-old fossil has turned our understanding of spider evolution on its head, suggesting that arachnids evolved in the ocean, not on land, as previously believed. Scientists studying the brain of Mollisonia symmetrica, a marine creature from the Cambrian period, found striking similarities to modern spider neuroanatomy.
The discovery challenges long-held assumptions about the origins of spiders and their relatives. Fossil evidence had suggested that arachnids evolved in terrestrial environments, but the study’s findings indicate that these creatures may have originated in the ocean.
Researchers led by Nicholas Strausfeld of the University of Arizona closely examined the fossilized brain and nervous system of Mollisonia symmetrica and found a unique organization that matches modern spider brains. This arrangement is believed to provide shortcuts for neuronal control, enabling spiders to exhibit remarkable dexterity and hunting abilities.
The study’s findings suggest that arachnids may have evolved from marine ancestors and later adapted to terrestrial life, influencing the evolution of insects and other animals. The discovery provides a significant insight into the evolutionary history of arachnids and highlights the importance of studying fossils in understanding complex biological processes.
Source: https://scitechdaily.com/this-500-million-year-old-sea-creature-had-a-brain-like-a-spider