Red Spitting Cobra
© AMNH / Denis Finnin
Red Spitting Cobra
Why spit venom from six feet away--stopping, but not killing, an enemy? To say, "Look out!" and gain time to escape.
To spit, the snake squeezes muscles around its venom gland, a modified salivary gland. The pressure forces a small jet of venom through a narrow tube in the fang. The toxic liquid hits an angled surface-the splash plane--which shoots it through a small hole in the front of the fangs. The fangs of non-spitting cobras don't have an angled plane.
Perhaps cobras evolved spitting--a defensive act--because their ancestors lived in a world of hoofed animals. Shooting painful venom might have been one way to avoid being trampled. Scientists think rattlesnakes' rattles may have evolved for a similar reason.
Spitting cobras hardly ever miss their targets: the eyes of the animal they are warning. In experiments, some species hit a researcher's goggle-covered eyes in 10 out of 10 tries.
Spitting cobra venom can contain nerve toxins and other harmful substances. It burns the cornea-the transparent window over the eye-causing severe pain and, sometimes, permanent blindness.
Meet the Family
Elapidae, the family that includes cobras--and the Eastern Green Mamba, in a case near by--is a group of highly venomous snakes. Most are small, but a few of the large species are deadly to humans. Some have taken up life in the sea.
© Robert Valentic / naturepl.com
Common Death Adder (Acanthophis antarcticus)
Common Death AdderAcanthophis antarcticus
Its bulky body and long fangs are like a viper's, but this Australian snake is a cobra relative--and it has the powerful venom to prove it. A Death Adder sometimes lures prey by wiggling its distinctively colored tail.
© Michael Fogden/DRK Photo
Indian cobra (Naja naja)
Indian CobraNaja naja
All cobras, including this one, rise to a third or more of their length and show their hoods in warning when disturbed. The hood is skin stretched over long, flexible ribs, like half an umbrella. The cobras we see "charmed" by snake charmers aren't listening to the flute but watching its movement.
© Anthony Bannister/NHPA
Pelagic sea snake (Pelamis platurus)
Pelagic Sea SnakePelamis platurus
This snake spends its whole life in warm Indo-Pacific ocean waters. A paddlelike tail enables it to swim and dive; strong venom helps it subdue the fish it eats. Females come into shallow water to give birth.
NAME: Red Spitting Cobra; Naja pallida
SIZE: 1.5 meters (60 inches)
RANGE: Eastern Africa
DIET: Frogs, rodents, birds