University of Florida scientist have compared the mitochondrial DNA of several different arachnids in an effort to map out just far back these critters’ ancestry goes.
GAINESVILLE, Fla. — Halloween is the only holiday when spiders and other arachnids get a little respect from humans, and a new University of Florida study suggests they deserve more, because they’ve apparently managed to survive a very, very long time.
By analyzing gene sequences in modern-day spiders, scorpions, ticks and mites, researchers have estimated that these invertebrates first appeared on Earth roughly 400 million to 450 million years ago.
Also in the news are Mercury and Hubble. New images of mercury indicate that it was an “active planet” at one time. In other words, rather than just an inert hunk of rock getting banged around by other celestial bodies, it also had volcanoes, which helped shape it. (More about the mission here.) As for Hubble, the telescope had been out of service for a little while, but is back up and running.