Horned lizards

Horned lizards
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.

References:
http://animals.nationalgeographic.com/animals/reptiles/horned-toad/
http://en.wikipedia.org/wiki/Horned_lizard

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World's Weirdest - Blood-Squirting Lizard
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