A woman’s bizarre video of a snake-like creature with “two heads, three eyes and weird skin” went viral with more than 19 million views, and it’s easy to understand why.
The dark brown and white striped creature looked like a stubby snake with a head at each end and a single “blinking eye.” But when she flipped it over with a stick she discovered several tiny, wiggling legs underneath.
“Can somebody tell me what this is?” a confused Lujan Eroles asked her Facebook friends, sharing videos and a photo of the odd-looking creature that she spotted in the courtyard behind her home in Santa Fe, Argentina.
The woman’s inquiry was shared by more than 180,000 people and received thousands of responses.
“A pokémon?” one Facebook user joked.
“It’s a worm, with one head and a tail,” another suggested.
Finally, more than a month after Eroles posted the viral video, she got her answer: It’s a caterpillar — a hawk moth caterpillar, to be precise.
“Most hawk moth caterpillars are known to disguise themselves as snake-like creatures to appear dangerous and protect themselves from predators,” reports National Geographic. “As caterpillars develop and get closer to becoming moths or butterflies, the metamorphosis process completely changes their body structure, and a large part of that involves putting on body fat, making them even tastier.”
When a hawk moth caterpillar feels threatened, it can expand its tail to take on the shape of a snake’s head to scare off any potential predators, which is what it was most likely doing when Eroles approached.
The caterpillar usually changes its appearance so birds above don’t recognize them.
“You think you’ve got this tasty hot dog you’re going to eat, but it turns around and puffs up its head to make it look more like a snake,” Katy Prudic, an entomologist at the University of Arizona, told National Geographic. “What happens is, the predator will often drop the prey or run away.”
The “blinking eye” is key to the caterpillar’s disguise.
When approached or harassed, the caterpillar can produce the effect of a blinking eye.
“This ‘blinking’ is an extension of eye mimicry or at least draws attention to the eyespot, functioning to startle or intimidate would-be predators,” a paper in the Journal of Natural History explains.
Eroles may have been frightened by the creature, but she didn’t need to be. The caterpillar appears much more dangerous than it actually is — after all, that is its whole goal.
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