# defense technics of lizards



## Death in #'s (Apr 29, 2003)

a little info on defenses that some lizards posses

-----------------------------------------------------------------------------------
chameleon is endowed with the anatomical equivalent of rearview mirrors. Renowned for its ability to change colors, this lizard possesses something unique to the animal kingdom - both 3-D vision and the ability to see ahead, to the side and behind, with each independently operating eye able to scan a 180-degree arc.

This master hunter, which deploys a lightening-fast tongue that reaches perhaps 1½ times its body length, has the best of both worlds: While one eye looks to the port side for prey, the other can look starboard - or even in its wake - for oncoming predators. And the turret-like eyes do their work while the chameleon's head and body remain stock-still.

But the most innovative eyes may belong to some North American species of horned lizard, small anteaters equipped with gladiator-like armor, which may be picked on by hungry foxes and coyotes. When cornered, this lizard can squirt blood droplets from a sinus beside its eyes, shooting the blood into the mouth of its attacker.

Wade Sherbrooke, a horned lizard specialist who runs the American Museum of Natural History's Southwestern Research Station, writes that the blood "appears to have a repulsive taste to kit foxes and probably to other canids but, as I discovered when I first tried it (the things we do for science!), it was not particularly offensive to my taste buds." 
-----------------------------------------------------------------------------
Some geckos can scale virtually any vertical surface and - using claws, toe pads and special muscles - even cling upside-down on a ceiling, as if immune to the Earth's gravitational pull.

The sand skink escapes predators by slithering underground, where it remains buried until the coast is clear. The ocellated skink, equipped with powerful hind legs and a wedge-shaped snout, digs tree-side tunnels for safe haven.

Some lizards stand on their hind legs and sprint from harm's way. And then there's the chuckwalla, a rock-dweller native to the southwestern United States and northwestern Mexico. When danger encroaches, this foot-long member of the Iguanidae family can compress its body and squeeze itself into a narrow crevice, where it often remains undetected. If caught, it can inflate its lungs until its wedged-in body is too large to be pulled free by a frustrated enemy.

When a predator appears, the 6-inch gliding gecko from Thailand leaps from its tree perch and spreads its legs and tail: Expanding folds of skin then act like tiny parachutes to guide the reptilian air-sailor to its next limb. 
----------------------------------------------------------------------------
Some lizards have prehensile tails, which can wrap around a branch, monkey style, and give them an added measure of security from their high-up vantage point. Tails of these species do not break off easily.

Other lizards let attackers "amputate" their tails with just a slight tug, sacrificing this body part in return for ultimate escape. Autotomy (the loss of body parts) occurs in the majority of lizards, and in fact also occurs in invertebrates, salamanders and even some mammals. For most species, a lizard's tail will regenerate.

Some lizards have brightly colored tails, which draw an attacker's attention away from the head and other vulnerable body parts. The tail of the Western spring-tailed gecko of Australia is equipped with glandular structures that squirt a noxious secretion at an attacker, effectively ruining the taste of its intended meal.

A lizard like the Gila monster uses its tail as a defense against starvation: It stores excess fat in its tail, which allows the animal to survive during times of food shortages. When rabbits, rodents and bird eggs return to abundance, the shrunken tail regains its heft.

Girdle-tailed lizards have large, spiked scales encircling their tails, and effectively thrash this weapon to ward off would-be attackers. The dabb spiny-tailed lizard, a foot-long member of the Agamidae family of the rocky deserts of northern Africa, has a strong, spiny tail that, when violently thrashed before an on-comer, may serve as an effective deterrent. 
-------------------------------------------------------------------------------------
When lolling amid foliage, the Malagasy chameleon is a dull, dull green. But disturb this Madagascar lizard and it transforms itself into a mixture of bright yellows, whites and blacks that give it the look of a 1960s psychedelic poster. In fact, when some chameleons duke it out, they heave color displays at each other (rather than bite) until one waves the white flag, returns itself to a nondescript juvenile color and heads off in defeat.

Color plays a major defensive role for many lizards. In eastern Australia, the 6-inch leaf-tailed gecko is nearly indistinguishable from the tree bark to which it clings; green lizards of the Central American rainforest blend so seamlessly with their surroundings that they appear to be another component of the flora, rather than the fauna. At night, the color fades from Old World chameleons' skin and, perched at the end of twigs, they're knockoffs for white leaves.

The Australian blue-tongued skink has a brightly colored tongue that, when displayed before an aggressor, becomes a tool of intimidation. And the Australian frilled lizard is endowed with brightly colored neck pleats that, when unfurled toward an aggressor (while the lizard opens its mouth and hisses), can send many predators running for cover
---------------------------------------------------------------------------------------------
While many lizards are desert dwellers, others live near water, or even, in the case of the Galapagos Marine Iguana, travel and feed at sea.

Australian water dragons and the 4-foot-long sail-tailed water lizard of Sulawesi, Indonesia, retreat to the water when pursued.

The European wall lizard, an adept climber that can scoot up sheer rock faces, will go headlong into the drink to escape trouble.

The Nile monitor, a stout and intimidating 6-footer of sub-Saharan Africa, typically forgoes combat for the safety of river-bottom vegetation.

And the green iguana will plunge from a tree, swim with ease, then dive to safety. It may even catch an hour-long underwater nap while waiting for trouble to retreat.

But the real waterborne wizard is the basilisk, a member of the Iguanidae family that lives besides the rivers and swamps of the Central American rainforest. The basilisk is outfitted with skin flaps on the toes of its hind feet. The skin flaps remain folded up when the 2-foot-long lizard traverses the jungle. But when nearing water, the lizard makes a dash on ground on all fours, gains speed, then lifts its arms and literally sprints across the water's surface on its hind legs, supported in part by the extra skin flaps. The feat has earned this water-walker an apt nickname: the Jesus Christ lizard. 
----------------------------------------------------------------------------------
Some chameleons are necessarily picky eaters (downing a live scorpion, for instance, could involve receiving a nasty sting). For example, Chameleo namaquensis of arid areas in parts of southern Africa may use well-honed ploys to disarm dangerous opponents by striking them in vulnerable spots. This species then systematically dismantles its prey (lopping off claws, spitting out the victim's stinger, then examining the remains) before digging into a well-earned lunch.

In some cases, a lizard's mere anatomy is enough to discourage even the most famished predator. Some, like the thorny devil of Australia, are covered with warts, knobs and a miniature mountain range of chocolate chip-like horns. But sometimes even ultra-spiny skin isn't enough to dissuade a determined predator, so other strategies are called for. To deter snakes, an armadillo lizard can roll into a scaly coil by putting its tail into its mouth. This bicycle tire-like meal can be too tough to swallow. 
---------------------------------------------------------------------------------
Defensive-minded lizards can effectively use their heads as both bona fide weapons and instruments of psychological leverage. Some chameleons are equipped with horns or horn-like appendages (the former are hard and bony, the latter are flexible) that turn them into four-legged battering rams.

Similarly, the horned agama, native to Sri Lanka, wields a small horn on the tip of its nose. Some lizards, such as the Australian thorny devil, sport a head (as well as a body) covered with large, imposing spikes. Other lizards have the equivalent of helmets atop their heads, while so-called plated lizards are outfitted with special shields on the front part of the head.

The toad-headed agama has mustache-like folds of skin on either side of its mouth that are distended during threat displays, and, with its mouth agape, enlarge the apparent size of its head.

The bearded dragon has both the physical and psychological spectrum covered: This 2-foot Australian lizard is equipped with a spiny flap of skin on its throat that is in its own right intimidating. But when this dragon needs an edge, it can unfurl that "beard" to ominous proportions. 
-------------------------------------------------------------------------------------
Unlike some of their close relatives among snakes, very few lizards have the ability to deliver a venomous bite, either to subdue prey or in self-defense. The world's only two species of venomous lizards are the Gila monster and beaded lizard. The Gila monster is found in the southwestern United States and northwestern Mexico; the beaded lizard lives farther south in western Mexico and Guatemala.

The venom glands are housed in their bulging lower jaws, and both species literally chew the venom into their prey or antagonists rather than delivering a physician-like injection. This venom delivers a painful, toxic shock, making it an effective defense.


----------



## piranha45 (Apr 8, 2003)

yes, I noticed that post in the other thread in the science forum. Very interesting stuff.


----------



## Death in #'s (Apr 29, 2003)

piranha45 said:


> yes, I noticed that post in the other thread in the science forum. Very interesting stuff.


 i delited it on that thread and transfered it here
so more people can read it


----------

