Lizards are diverse and are found all over the world. Their skin is dry and thick, consisting of flakes of varying shapes; the pineal gland eyes are located on the back of the head and can sense light and adjust the biological clock. The skull of the head can be moved. Males have adapters. Some lizards can shed their tails to distract predators. Most limbs are shorter, and some have only forelimbs or hindlimbs. The shape of the tongue varies depending on the species.
Characteristics of lizards
Lizards represent a reptile population that is found in any corner of the planet except Antarctica. Includes many different kinds. They vary greatly in size, ranging from geckos with centimeters in length to Komodo monitor lizards up to 3 meters long. The surface of the skin is covered with tiny scales and stratum corneum. It is slender and has a long tail. Most lizards have limbs, but some have only two legs, and some even lose their limbs completely, such as the slow limbless lizard, which retains only the marks on the limbs. Most lizards have movable eyelids in their eyes. Vision is particularly developed, and some species can distinguish colors. Skin changes color due to environmental changes or emotional agitation. One of the most representative is the chameleon. The skin under its throat has a pronounced color that unfolds when threatened. In addition to skin color, they use body posture and movement to communicate, especially when attracting or driving away their partners.
Their hearts have two auditory ears and one ventricle that is not completely separated. There is a urinary bladder and cloaca. It feeds on insects and rodents, and some species can eat plants. Only one species of lizard (The Genus Diffodonidae) is highly venomous, such as the Sheila, but recent studies have shown that komodo dragons may also have toxic glands in their jaws.
Diversity of lizard species
Lizards of 20 families have been found. The iguana is the iguana family of the Old World, which is mainly distributed in Africa, Asia and Oceania, and is represented by moro lizards, common lizards and water lizards. The umbrella lizard is famous for its skin collar around its neck; the flying lizard can glide freely through the bushes because of the stretch of the skin on its ribs. There are about 300 species of American lizards, including the most common American iguanas, of which the Antillean green lizard, chameleon lizard, sea lizard and tropical American Tibetan lizard are the most famous. The chameleon family is widely known for the change of color of its skin. In addition, their toes are pincer-like, and the eye is located above the spherical structure and can rotate freely in all directions. The snake lizard family includes some slow-limbed lizards whose limbs are very short or even missing, and like other lizards, they can cut off their tails on their own. For these reasons, they are also known as crystal snakes. The guardian family includes geckos as well as all herbivorous lizards. It has filaments on its toes for easy climbing on smooth or vertical surfaces. The suborder Lizards include some of the most famous members of the order Plesiosaurs, such as lizards. They are carnivorous, with a bifurcated tongue, a long tail, and fully developed limbs. The family is very similar to the suborder Lizards, but the forelimbs are short, and some species even have missing limbs. The monitor lizard family, such as the Komodo dragon, has a strong body, a broad head, a slender and strong body, and can defend itself by swinging its tail vigorously.
How lizards deal with predators
In addition to camouflage, lizards have other means of self-protection, such as intimidating aggressors by opening their mouths, swinging their heads, bending their limbs, etc. Some will also be hit with their tails, and in some extreme cases they will pretend to be dead. Self-amputation of the tail is the most notable feature of some lizards, a phenomenon known as self-truncation. The tail can be reborn through the development of the chondral tube. The tail is very important to these reptiles because the tail acts as their replacement organ and can be used to keep the body balanced when moving. In addition, it also plays a role in courtship during the breeding period.
The "Third Eye" of the Lizard
Between the lizard's brainstem and the neurons of the brain hemisphere, a secretory gland that can be divided into two parts is developed. One of them, called the pineal gland, is located next to the brain neurons. The other part is the parapachyllaceous body, which in some lizards develops to the epidermis of the brain through the gaps in the skull parietal bone. The parapachyllaceous gland is very pronounced on an organ called the third eye or cranioceploid eye. The craniocera is composed of a lens and a retina, which is light-sensing, that is, it can perceive light, and can sense changes in light every day and in each season. But since the retina and lens of this eye are only initially developed, it is impossible to form an image. It looks like a transparent scale or a dot on the head. Depending on the light received, it can promote the production of hormones, especially the reproduction activities. In addition, it can also play a role in the regulation of body temperature. By observing changes in light and shadow, the cranioceploid eye can provide early warning when the trapper approaches from above.
Many people mistakenly think that lizards are close relatives of dinosaurs, in fact, lizards are relatively distant from dinosaurs, among living animals, birds are the closest animals to dinosaurs, and lizards can only be regarded as "distant relatives".