Daddy longlegs are arachnids, but they’re not spiders, although they’re often mistaken for them due to their similar appearance. Also called harvestmen, daddy longlegs are actually members of the order Opiliones. This order evolved over 400 million years ago, way before the time of the dinosaurs — making them one of the oldest known groups of arachnids in existence. Their long history has allowed them to diversify into over 6,600 species, with adaptations that enable them to thrive in a wide range of environmental conditions. But there’s much we still don’t know about their evolutionary histor…
