A newly studied fossil from 500 million years ago may help answer a big question: Did spiders first live in the sea or on land?
A team of scientists from the University of Arizona, along with international experts, believes spiders may have started in the ocean before moving onto land.
The fossil, called Mollisonia symmetrica, is from a long-extinct marine creature that lived during the Cambrian period. It was found to be very well preserved, especially its brain and nervous system.
For years, this animal was thought to be a distant relative of horseshoe crabs. But when researchers looked closely at its brain, they discovered something surprising, it looked more like the brains of modern spiders and scorpions.
This discovery suggests that Mollisonia symmetrica may have been one of the earliest ancestors of today’s arachnids. This is a group that includes spiders, scorpions, and ticks.
Professor Nicholas Strausfeld, who led the study, explained that scientists are still debating how arachnids evolved. He also guessed that these ancient creatures might have eaten early insects and millipedes when they first moved onto land.