Scientists look inside the ‘spider’ growing on the tip of a rare viper’s tail

By Ashley Strickland, CNN (CNN) — In the arid, inhospitable climate of western Iran’s Zagros Mountains, life has found a remarkable way to survive. Circling above, a bird glimpses what at first glance looks like a plump spider climbing on the rocks. But as the avian predator swoops in, it becomes the prey as something