Ancient Creepy CrawlyA fossil spider can be seen embedded in amber. The fossil, provided by the Florida Museum of Natural History, was discovered in the Dominican Republic and dates from the Miocene epoch, some five to 23 million years ago.
From Discovery:
Oct. 31, 2008 -- If it seems like spiders, scorpions, ticks and mites have been around forever, it's because they nearly have, according to new genetic research that found these arachnids first emerged at least 400 to 450 million years ago.
The study, published in the latest issue of Experimental and Applied Acarology, extends the known world presence of these creepy crawlies by over 200 million years. The oldest fossil spider is 125 to 135 million years old, while the oldest fossil scorpion is around 200 million years old.
These invertebrates could even have emerged much earlier than this latest study determined.
"A horseshoe crab dating to 475 million years ago provided one of our anchor dates, and this crab actually looked quite modern, as did a Devonian period (416 to 359 million years ago) mite that was one very modern-looking mite," co-author Marjorie Hoy told Discovery News.
Hoy, a University of Florida entomologist, added, "I don't think the individuals just suddenly appeared on Earth, so it's likely these invertebrates are even older than we estimated."
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