Sex determination in adults lizardshaving sexual dimorphism does not cause difficulties. Male basilisks, green iguanas, water agamas, and sailing lizards have a distinct crest on their heads and backs. In many species of chameleons, males have skin outgrowths on their heads. In other species, males have heel spurs. Male iguanas have laryngeal rags, as well as doubled scales behind the cloaca. Male geckos have preanal pores and the area around the cloaca is often greatly expanded.
Male toothfish have four rectangular preanal scutes, in females - only two. In males of many species of lizards, preanal and femoral pores or scales, or postanal and umbilical scales are found. True, the existence of preanal and femoral pores is cyclical in nature, therefore, establishing sex on them is not always possible. The truth is not always the signs listed above are expressed quite clearly. There are many types of lizards for which an external sex determination is not possible.
The puberty of lizards is determined mainly not by the size of their body, but by their age and the estimated duration of their life. When selecting a sexual partner in lizards, vision is much more important than smell. Therefore, in the terrarium, one can often observe complex mating dances of lizards.
An exception among all reptiles are geckos, for which acoustic signals are of primary importance in sexual life.
Readiness for mating in lizards is determined by climatic factors. As soon as the period of dark, cold and short winter days passes, the lizards begin to mate. For tropical species, the start of mating may be related to the onset of the dry season. In order for mating to become possible in the terrarium, care must be taken about suitable climatic conditions. Knowledge of the climatic features of lizards is a condition for their successful breeding.
The duration of the incubation period is highly dependent on temperature. To date, it has been established that for many species of lizards, the temperature of the cub can be influenced by temperature.
If the lizards mated in a terrarium and laid eggs, then they must be carefully dug up, numbered and transferred to an incubator. The eggs in the incubator should be in the same position as in the place of laying. If the egg is twisted, it can lead to abnormal development or death of the embryo. Egg laying should remain warm and moist, but not wet.
Soft, sticky gecko eggs are best left in the terrarium, as they are very easy to damage. Most often consisting of two eggs, the clutch can be protected from other lizards using a wire duct.
After hatching, the cubs are placed in a separate tank. Too high temperature in this terrarium initially leads to accelerated growth of young lizards, but in this case, animals often develop rickets and cramps due to vitamin B deficiency. For young animals, ultraviolet radiation is very important.
Viviparous lizard cubs should be reared in the same way as hatchery lizards.
Terrarium. Lizard breeding
The reproduction of lizards occurs mainly through sexual contact, with the exception of some species that reproduce by parthenogenesis. In this case, the offspring develops from the egg without its preliminary fertilization by the male.
Lizards are oviparous animals. They lay eggshells that develop for several weeks outside the mother’s body before they hatch. However, in some species of lizards, oviposition has formed. Their eggs are not covered by shells and remain in the female’s oviducts until the completion of embryonic development. Subsequently, already hatched cubs are born.
In South American skinks, eggs are devoid of yolk and develop in the oviducts, receiving nutrition from the mother through the placenta. Placenta in lizards is a special temporary formation on the wall of the oviduct, in which the capillaries of the mother and embryo come close enough to each other so that the latter receives oxygen and nutrients from her blood.
The number of eggs or calves in a brood can vary from 1-2 in large iguanas, skinks, and some geckos to 50 in other species.
Puberty in lizards usually depends on body size. In small species, it lasts less than a year, in large - several years. In some small forms, most adults die by laying eggs.
If you want to get offspring from the lizards contained in the terrarium, you must provide them with a suitable temperature and humidity level, taking into account their species characteristics. Particular attention should be paid to creating calm conditions for reptiles. Scientists have found that with various stresses the reproductive ability of lizards decreases, and in some cases elements of mating behavior do not appear at all.
The size of the terrarium also matters. Some species require a certain space for breeding, and if it is lacking, you will not be able to obtain offspring.
For reproduction, individuals who have reached puberty are selected. They must be healthy, mobile, brightly colored. The dimensions and proportions of the body should correspond to the average for each particular species.
It is important to properly form a community of lizards. Usually the following ratio of females and males is recommended: 3: 1 for chameleons, geckos, iguanas and agam, 3: 2 for skinks and real lizards, 2: 1 for monitor lizards. Males can be distinguished by their bright color, larger than that of females, in size, as well as by their behavior during the breeding season. Males of almost all types of lizards become very aggressive, their mating games take place in the form of fierce fights, when reptiles hiss, inflate their neck, make threatening movements and inflict sensitive bites on each other.
In some lizards - such as monitor lizards and venoms, it is sometimes difficult to determine sex visually. In this case, special methods are used: in particular, you can conduct a biochemical study for the content of male hormones. In any doubtful cases, it is better to consult a specialist from a veterinary clinic.
If you intend to keep a large number of lizards together, it should be borne in mind that a stronger male can suppress the weak. Therefore, after the formation of groups for breeding other reptiles, they are planted in a separate terrarium.
Lizards reproduce mainly through sexual contact.
It should be noted that when breeding in captivity some species, such as chameleons, you should especially carefully select a pair and carefully monitor the behavior of reptiles, as they may simply not like each other.
To stimulate reproduction, it is necessary to simulate natural conditions. To do this, first spend an artificial wintering for 4-8 weeks, during which feeding is stopped, the ambient temperature is lowered, and the daylight hours are reduced. During this period, you need to constantly monitor the state of reptiles. After the specified time, lizards are placed in the terrarium and gradually increase the temperature and humidity. Lighting should preferably be maintained for 15-16 hours a day for 3 weeks before the start of the breeding season. To achieve the best effect, you can apply ultraviolet radiation, as well as introduce vitamins and special feed additives into the diet of lizards. It should be borne in mind that females of some species may refuse food during pregnancy.
For the successful development of young lizards, it is recommended to regularly irradiate with ultraviolet light. This contributes to the assimilation of trace elements contained in the feed, and reduces the risk of infectious diseases.
For certain species of lizards - such as geckos and chameleons - it is not necessary to arrange an artificial wintering. To stimulate mating behavior, males and females are kept separately for some time at a temperature 3-4 ° C lower than usual, and then combined. For geckos in the terrarium, it is recommended to place the remains of the shell from previous clutches.
Most lizards breed only in certain seasons. Depending on the characteristics of a particular species, it can be both winter and spring-summer periods. Others can mate throughout the year, making several clutches. These natural features should be considered when keeping and breeding reptiles in captivity.
It can be noted that in lizards adapted to terrarium conditions, the seasonal nature of reproduction often disappears, and they can lay eggs at any time.
The duration of pregnancy differs markedly in different species of lizards. In ovoviviparous reptiles, this period is longer, since all stages of embryo development take place in the mother's body. In ovipositing lizards, gestational periods are somewhat shorter.
Lizards, like other reptiles, prepare a nest for future offspring by digging a hole in the ground. Under natural conditions, they can lay eggs in cracks and voids in the soil, in the burrows of rodents.
For home breeding, it is important to ensure that the layer of sand or gravel is of sufficient thickness so that animals can bury their eggs in it. For some species, pieces of bark can be placed in the terrarium, which at the same time serve as a shelter and a place for eggs to attach.
In terrarium conditions, both natural and artificial incubation are possible. Some lizards can guard the clutch until the young. If you intend to transfer the clutch to an incubator, you should be very careful with it, being careful not to damage the egg shell.
Viviparous lizards often take care of offspring not only in nature, but also in the terrarium. They protect the kids from possible danger and take them to warm places.
Incubation usually takes place at a temperature of 28-31 ° C and lasts 50-60 days for geckos and skinks, 60-80 days for iguanas, 130 days for venomous teeth, 170-180 days for Cape monitor lizard, and up to 190 for common chameleon days. The duration of incubation may depend on the ambient temperature, increasing as it decreases.
Humidity of the environment and the substrate in which the eggs are located is also important for the development of embryos. The value of this parameter is individual for each particular species.
To preserve the young, 4-7 days before its appearance in the terrarium, shelters for newborns should be equipped in which adult lizards could not penetrate. This reduces the likelihood of cannibalism.
Young reptiles are also recommended to be planted, which will provide them with the necessary living space for the proper development.
As food for newborn lizards, various small insects are given: crickets, cockroaches, and others. Depending on their species preferences, juveniles can be given pieces of fruit, cabbage and lettuce leaves, cottage cheese, and newborn mice. For harmonious development, vitamins and mineral supplements should be given. Sometimes young lizards refuse food, so artificial feeding is necessary.
Lizard: description, structure, characteristics. What does a lizard look like?
Usually, lizards are considered to be all reptiles with legs, but several of them without legs also belong to them. There are a lot of species of lizards, according to the estimates of zoologists on our planet there are more than 6000 different types of lizards, and all of them, of course, differ in their habits, appearance, color and habitat. Some of the particularly exotic species of lizards are currently on the verge of extinction, and for this reason are listed in the Red Book.
The most common real lizard has a body length of 10-40 cm. The body of the lizard is long, elastic, elongated and has a long tail.
Unlike their relatives of snakes, lizards have moving and divided eyelids. The legs of the lizard are of medium length, possess claws and are generally proportional to its body covered with keratinized scales. The skin of a lizard exfoliates during molting a couple of times per season; in some languages of the world, this amazing feature of these reptiles to change their skin even gave them a name. In particular, in our language, the word “lizard” comes from the old Russian word “speed”, which means “skin”, or “skin” if more literary.
The lizard tongue, depending on the species, has a different shape and size, as a whole it is mobile, and easily protrudes from the mouth. And some lizards use their tongue to fish at all.
The teeth of a lizard are also their weapons, with their help they capture and grind food, and for lizards sharp teeth literally cut the prey. Among the lizards there is also the only poisonous representative, named accordingly - a venomous tooth, which, with a bite, injects poison into its victim, thus killing it.
The skin of a lizard has, depending on the species, it can have a variety of colors and patterns.
The color (color) of the lizard also varies, which many of their species can change depending on the situation, sometimes literally merging with the surrounding area - color mimicry is one of the main means of protection. Usually, lizards have a combination of gray, brown and green colors.
How are snakes different from lizards?
Those species of lizards that do not have legs are almost the same in appearance as snakes. Such lizards include, for example, a copperfish, which many take for a snake, although in fact it is a lizard that simply does not have legs. But how to distinguish such a legless lizard from real snakes?
- The first difference between snakes and lizards is the eyelids. For snakes, the eyelids have fused and become transparent, for this reason snakes never blink. In lizards, on the contrary, the eyelids are mobile and blinking in their order of things.
- The snake has no hearing organs, but the lizard has them; on both sides of its head are ear openings covered by eardrums.
- Shedding and snakes and lizards occurs in different ways, snakes try to shed their skin in one fell swoop, before soaking in water, the lizards shed gradually, dropping pieces of skin.
How to distinguish a newt from a lizard?
Also, sometimes lizards are confused with newts, and, of course, they have a lot in common: a similar structure of paws and body, a snake-like head, a long rounded tail, movable eyelids and much more. But still there are a number of differences between it:
- The most important difference is the different structure of the skin, if lizards have always scaly skin, then in newts it is completely smooth and mucous to the touch.
- Newts do not know how to cast their tail, while lizards easily and simply get rid of this part of their body in case of danger.
- The lizards have a solid and ossified skull; in newts, it is cartilaginous.
- While lizards breathe exclusively with the help of the lungs, newts are able to breathe, both with the lungs and the gills, and even with the help of their skin.
- If lizards breed by laying eggs, then newts lead their reproduction process like fish - in water and through spawning.
The tail of a lizard. How does a lizard swing its tail?
One of the most amazing and unique features of the lizard, of course, is its ability to cast its tail in emergency situations, or autotonia, as this phenomenon is called scientifically. How does this happen? The contraction of the tail muscles of the lizard allows it to break the cartilaginous formations of the vertebrae and thus discard most of the tail.The blood vessels in this case are very narrow, and there is practically no loss of blood during this procedure. The discarded tail continues to wriggle for some time, which distracts the enemy, and the lizard manages to hide during this time. Over time, the tail of the lizard grows again, although in a somewhat shortened form.
An interesting fact: it also happens that after autotonia, not one, but two or even three tails grows in a lizard.
How to distinguish a male lizard from a female?
The male and female lizards look almost the same, although there are a number of signs by which one can determine the gender of the lizard.
- In some species of lizards, such as basilisks and green iguanas, males have a bright crest on their backs.
- Spurs on the legs are another sign of a “man” among lizards.
- You can also determine the gender of the lizard by the throat sacs that some species have.
In general, all methods for determining the sex of a lizard are not perfect, and it’s possible to know for sure whether a boy or a girl can only do this through a lizard blood test for testosterone made in a professional veterinary clinic.
How many lizards live in nature and at home?
The longevity of lizards is highly dependent on their species, usually, the shorter the lizard, the shorter its lifespan. So the smallest representatives of the kingdom of lizards live on average about 3 years, while the largest: iguanas and monitor lizards live for 50-70 years, almost like people. And in captivity, they live longer than in natural hazards.
Where do lizards live?
Lizards live on all continents, with the exception, of course, of Antarctica. In general, they like a warm climate, they can be found in forests, meadows, steppes, deserts of any part of the world. They move perfectly on any surface, cling tightly to them with their paws.
An interesting fact: the rocky species of lizards are simply excellent jumpers, the height of their jumps can sometimes reach up to 4 meters.
What do lizards eat in nature?
Lizards are omnivorous animals; after all, they are more predators and the diet of their food directly depends on the type and size of a particular lizard. Small lizards eat various insects: butterflies, grasshoppers, locusts, snails, various worms. Larger lizards, for example, the monitor lizard prey on various small animals: frogs, snakes, mice, do not mind eating bird eggs. And the biggest lizards - monitor lizards from Komoda Island even attack wild boars, buffaloes and deer.
Lizards first sneak up to their prey, then make a rapid jerk and overtake it with their claws and sharp teeth.
Since lizards are omnivores, they can also eat vegetarian food - pollen from plants, ripe fruits, tree leaves. There are species of lizards that completely lead a vegetarian lifestyle, but most lizards still like to eat meat.
Enemies of lizards in nature
But the lizards themselves, under natural conditions, have many enemies, among them there are, including their closest relatives, for example, the same monitor lizards gladly eat other small lizards. They are attacked by birds of prey (owls, eagles, hawks), predatory animals: foxes, bears, wolves, martens, and sometimes even cats. A great threat to many lizards is also snakes.
These include the following families:
- real lizards living in Eurasia, Africa and the USA,
- nocturnal lizards inhabiting Cuba and Central America,
- gerrosaurs - “inhabitants” of the Sahara and Fr. Madagascar,
- skink - live everywhere, mainly in the tropics,
- Theiids - live in South and Central America,
- girdle-tails - live south of the Sahara and Madagascar,
- hymnophthalmids - distributed from the south of Central America to the south of South America.
This includes the largest representatives of lizards - monitor lizards, which are also divided into several families. Lizards live in many parts of Africa, Asia, Australia, as well as in New Guinea and many islands of Oceania.
Komodo lizard - the largest lizard in the world
And the most dangerous. The Komodo lizard, the largest among all existing lizards in the world, deserves special mention. Komodo monitor lizards live in Indonesia on Komodo Island and amaze with their simply incredible size - Komodo monitor lizard is up to 3 meters long, weighing 80-85 kg. Not surprisingly, these giant lizards sometimes even attack cattle.
The Komodo lizard is also a serious danger, including for humans - there have been several cases of attacks of these lizards on people that ended in death for the latter.
The mating season in lizards occurs in spring or early summer. Large lizards breed once a year, smaller several times a season. If several males pretend to be one female, then she gets the largest of them. Smaller male pangolins prefer not to fight a strong opponent. However, if the size of the applicants is equal, then a fight breaks out between them, during which the males violently bite each other. As a result, the female gets a stronger winner.
Some time after fertilization, the pregnant female lays eggs, small lizards lay 4 eggs at a time, while larger ones can lay up to 18 eggs at a time. Egg sizes also vary, for example, in a small round-toed gecko, the size of an egg does not exceed several millimeters in length, while in a Komodo monitor lizard, the egg is 10 cm long.
Caring mother lizards bury their masonry underground or hide in various secluded places, caves, burrows. The incubation period in lizard eggs lasts from 3 weeks to 1.5 months, after this period small lizards appear, which immediately begin an independent life.
How to feed a lizard at home?
And many more exotic species of lizards are very popular terrarium animals, among them a Yemeni chameleon, a bearded agama, a real iguana and others. With proper care, the lizards breed well and feel at ease. But if you still decide to have a pet lizard, then you will be faced with the question of proper feeding of so many exotic pets.
Fortunately, in terms of food intake, the lizard is not whimsical, in the warm season it needs to be fed three times a day, and in winter, due to the low activity of the lizard itself, it can be fed only twice a day. Well, meal worms, grasshoppers, spiders, fresh chicken eggs and pieces of raw meat are suitable as food for a lizard. It is said that lizards are very fond of a mixture of crushed boiled chicken, grated carrots and lettuce. It is also very important that the lizard in the terrarium always has fresh drinking water.
Interesting facts about lizards
- Basilisk lizards are able to move on water. And this is not a biblical miracle, but a physical law of nature, water movement is achieved by quick and very frequent sorting of the hind limbs of the lizard.
- Lizards, like many other animals, do not distinguish colors, but unlike many of them who see the world in black and white, lizards look at it through orange glasses in the most literal sense - they see the whole world as different shades of orange.
- Colombian gourmets consider the eggs of some lizards to be the greatest delicacy. They even specifically catch pregnant female lizards and iguanas, cut their stomach, take out their eggs, rub wood ash into the wound itself, after which the female is released, and the eggs go to the dining table.