Within the rocky hills of western Iran, one of many world’s strangest snakes lives. At first look, the spider-tailed horned viper (Pseudocerastes urarachnoides) appears to be like like another desert viper—camouflaged towards pale stone, immobile, ready. However then its tail twitches, and the phantasm begins.
As a substitute of a easy tip, this snake’s tail ends in a bulb with spiny, leg-like scales that transfer identical to a spider scuttling about. Hungry birds, pondering they’ve noticed a straightforward snack, swoop all the way down to seize the “insect.” That’s when the viper strikes—lightning quick, in lower than 1 / 4 of a second. The hunter turns into the hunted.
Though locals had lengthy spoken a few snake with a “spider tail,” scientists solely formally described the species in 2006 after finding out museum specimens and finally discovering residing snakes in Iran’s Zagros Mountains. What stood out was the tail: a decoy so elaborate that no different reptile on this planet has something fairly prefer it.
Story continues beneath this advert
How the trick works
When the viper lies coiled amongst pale rocks, its physique blends in virtually completely with the panorama. All that strikes is the tip of its tail, which the snake waves in jerky little bursts, identical to a spider. To a hen looking out for bugs, it’s irresistible. As quickly because the hen lands, the viper lunges, sinking its venomous fangs into the prey.
Discipline research have proven that grownup vipers largely use this technique to catch small migratory birds, whereas youthful snakes, whose tails haven’t but developed the complete spider-like lure, feed extra usually on lizards. In different phrases, the “faux spider” grows extra convincing because the snake itself matures.
When the viper lies coiled amongst pale rocks, its physique blends in virtually completely with the panorama (Supply: Wikimedia Commons)
Evolution’s little masterpiece
Many snakes use their tails to wiggle and tease prey, however this viper takes it to an excessive. Over 1000’s of years, pure choice has formed a tail that doesn’t simply transfer like a spider, however really appears to be like like one, proper all the way down to the “physique” and “legs.” For a predator that depends on ambush in a harsh atmosphere, this mimicry is a intelligent method of turning the tables on fast-moving birds.
As a result of the spider-tailed viper lives solely in a small area of Iran, conservationists fear about its survival. It was added to CITES Appendix II in 2019, which implies commerce within the species is restricted, and in 2022, the IUCN Purple Record up to date its standing to Close to Threatened. For such a uncommon and strange creature, these protections are an essential step.
