Ancient daddy longlegs were a lot more hair-raising than today's. A newly described 305-million-year-old fossil of the familiar spider reveals that the primitive species, dubbed Hastocularis argus, had an extra pair of eyes. According to x-ray scans, described this week in Current Biology, one eye was located on each side of the head, while the other set was located front and center. The researchers suspect the species may have lost its extra set of eyes after it moved into darker environments, such as caves, where they didn't have as much need to see, Wired reports.
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