The spectacular and Striking Horned lizard (Phrynosoma). (28 Pics)

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Horned lizards are a genus (Phrynosoma) of lizards which are the type genus of the family Phrynosomatidae. .Horned lizards are morphologically similar to the Australian thorny devil (Moloch horridus), but are only distantly related. They also have other similarities, such as being sit-and-wait predators and preying upon ants, so the two species are considered a great example of convergent evolution.Horned lizards use a wide variety of means to avoid predation. Their coloration generally serves as camouflage. When threatened, their first defense is to remain still to avoid detection. If approached too closely, they generally run in short bursts and stop abruptly to confuse the predator's visual acuity. If this fails, they puff up their bodies to cause them to appear more horned and larger, so more difficult to swallow. At least four species are also able to squirt an aimed stream of blood from the corners of the eyes for a distance of up to five feet. They do this by restricting the blood flow leaving the head, thereby increasing blood pressure and rupturing tiny vessels around the eyelids. This not only confuses predators, but also the blood tastes foul to canine and feline predators. It appears to have no effect against predatory birds. To avoid being picked up by the head or neck, a horned lizard ducks or elevates its head and orients its cranial horns straight up, or back. If a predator tries to take it by the body, the lizard drives that side of its body down into the ground so the predator cannot easily get its lower jaw underneath the lizard.

from:http://en.wikipedia.org/wiki/Horned_lizard