Whip spiders, also known as tailless whip scorpions, are neither spiders nor scorpions. These strange creatures belong to a separate arachnid order called Amblypygi, meaning “blunt rump” in reference to their lack of tail. Very little was known about whip spiders before the turn of this century, but a recent flurry of behavioral and neurophysiological studies has opened a window into their unique sensory world. Researchers have discovered that some species engage in curious behaviors, including homing, territorial defense, cannibalism, and tender social interactions — and it’s all mediated by a pair of unusual sensory organs. Read all about whip spiders in my latest piece for The Scientist: Meet the Arachnid That May Add a New Chapter to the Book on Sensory Biology .