305-Million-Year-Old 'Almost Spider' Unlocks Arachnid History

The arachnid, locked in iron carbonate for 305 million years, reveals the stepwise evolution of arachnids into spiders. "It's not quite a spider, but it's very close to being one," said study researcher Russell Garwood, a paleontologist at the University of Manchester in the United Kingdom. Arachnids are an ancient group with murky origins, Garwood told Live Science.