Remember that scene in Homeward Bound when Chance, the lovable rascal of a pooch, got in a tussle with a porcupine? “Ah! He bit me with his butt!” said Chance, his face full of quills. As it turns out, Chance could have had it much, much worse. According to new research, porcupine quills aren’t just a painful deterrent, they’re deadly daggers that porcupines are not afraid to use to kill.
They identified four defenses that the animals employed, in order of increasing aggression: quill erection, tail rattling, stamping and growling, and backwards or sideways attacks. The porcupines never used the latter two in one-on-one encounters, but rather as last resorts when an individual was outnumbered, or if multiple porcupines were present and more likely to inflict serious damage. In one such case, two porcupines ran backwards, forcing a dog into their den, where they fatally impaled it with their quills.
It should not be surprising that spines evolved for defense can do their job; it is a reminder to not take any creature’s anger too lightly. Piss porcupines off enough, and they’ve got the tools to get you back.
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