World’s Oldest Scorpions May Have Moved From Sea to Land 437 Million Years Ago

via Smithsonian

Half a billion years ago, the continents were quiet. Earth’s animals—represented largely by shelled mollusks, armored arthropods, and a smattering of wriggly, jawless fish—breathed with gills, not lungs, and hunted their prey at sea.

But sometime, possibly during the Silurian (the geologic period spanning 443 million to 416 million years ago) an intrepid creature, likely equipped with sturdy limbs and a set of gas-cycling tubes that could leech oxygen from air, decided to crawl ashore. In habitually venturing out of the ocean, this animal paved a habitat-hopping path for countless lineages of land-dwellers to come—including the one that eventually led to us.

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