The Incredible Journey of Ancient Spiders
A genus of spider that can only travel by land may be the key to understanding how continents and land masses have drifted over the millennia. The spider group, called liphistiids, are sometimes known as a “living fossil” because of how little they have changed over millions of years.
Currently, this chubby little burrow-dweller lives only in East and Southeast Asia. The arachnid’s existence dates back to at least 295 million years, and its original fossil ancestor was discovered in France.
Since the Earth was once a single, giant continent, much about how “continental drift” – or the breaking apart of the one land mass into continents – occurred still isn’t fully understood. But the spider’s long migration patterns may shed some light onto what the possible intercontinental routes existed.
Recent research examined 2,000 specimens to determine that, about 24 million years ago, the older cousins evolved into the current 89 species. Prior to that, the first liphistiid branched out from their ancient ancestors between 39 and 58 million years ago. The more recent split coincided with a period when the subcontinent of Eurasia met up with India.
The researchers are continuing to hypothesize which of three possible routes brought the spiders over land from Europe to Asia.