What Spider Fossils Tell Us About Earth Millions Of Years Ago

The global distribution of spider fossils says a lot about which parts of the earth were once hospitable to some spiders. Researchers have found fossilized spider species in parts of the world where environmental conditions would not have favored their survival. So how did these ancient spiders live in seemingly inhospitable locations so long ago?

One obvious theory to explain the presence of bug fossils in seemingly unfavorable conditions has to do with the theory that the earth was once comprised of one large continent surrounded by ocean. Back when earth had only one large continent, environmental conditions were very different, which would explain why spider fossils are found in geographical locations that today seem implausible.

Researchers have long wondered why arthropods and other animals are found fossilized in parts of the world that are not conducive to arthropod survival. The previous theory involved early arachnids migrating across short term bridges formed from ice that allowed insects to migrate to locations far from their home. Despite the soundness of the previous theory, many more scientists are beginning to embrace the “one continent theory.”

Have you ever spotted a spider that you knew was not a species of spider native to the geographical region where you found it? How do you think most invasive nonnative insects arrive on US soil?