Where does the tuateria live? Guttery: structural features

The most ancient reptile, preserved from the time of dinosaurs, is the three-eyed lizard Hatteria, or tuatara (lat. ) is a species of reptile from the order Beak-headed.

For the uninitiated person, tuateria ( ) is simply a large, impressive-looking lizard. Indeed, this animal has greenish-gray scaly skin, short strong paws with claws, a crest on its back consisting of flat triangular scales, like agamas and iguanas (the local name for tuateria is tuatara- comes from the Maori word meaning "spiky"), and has a long tail.

However, the hatteria is not a lizard at all. The features of its structure are so unusual that they established for it special squad in the class of reptiles - Rhynchocephalia, which means “beak-headed” (from the Greek “rynchos” - beak and “kephalon” - head; an indication of the premaxillary bone curving down).

True, this did not happen immediately. In 1831, the famous zoologist Gray, having only the skulls of this animal, gave it the name Sphenodon. After 11 years, a whole specimen of the tuatara fell into his hands, which he described as another reptile, giving it a name Hatteria punctata and classified as lizards from the aga family. Only 30 years later Gray established that Sphenodon And Hatteria- same. But even before this, in 1867, it was shown that the resemblance of the tuatara to lizards is purely external, and in terms of its internal structure (primarily the structure of the skull), the tuatara stands completely apart from all modern reptiles.

And then it turned out that the hatteria, which now lives exclusively on the islands of New Zealand, is a “living fossil”, the last representative of a once widespread group of reptiles that lived in Asia, Africa, North America and even in Europe. But all other beaked heads became extinct in the early Jurassic period, and hatteria managed to exist for almost 200 million years. It is surprising how little its structure has changed over this huge period of time, while lizards and snakes have achieved such diversity.

Very interesting feature tuateria - the presence of a parietal (or third) eye, located on the crown between the two real eyes*. Its function has not yet been clarified. This organ has a lens and a retina with nerve endings, but is devoid of muscles and any devices for accommodation or focusing. In a baby tuatara that has just hatched from an egg, the parietal eye is clearly visible - like a bare spot surrounded by scales that are arranged like flower petals. Over time, the “third eye” becomes overgrown with scales, and in adult tuatara it can no longer be seen. As experiments have shown, the hatteria cannot see with this eye, but it is sensitive to light and heat, which helps the animal regulate its body temperature, dosing the time it spends in the sun and in the shade.

As excavations show, not so long ago tuataria were found in abundance on the main islands of New Zealand - North and South. But the Maori tribes, who settled in these places in the 14th century, exterminated the Tuatara almost completely. The dogs and rats that came along with the people played an important role in this. True, some scientists believe that the hatteria died due to changes in climatic and environmental conditions. Until 1870, it was still found on the North Island, but at the beginning of the 20th century. has been preserved only on 20 small islands, of which 3 are located in Cook Strait, and the rest are off the northeastern coast of the North Island.

The appearance of these islands is gloomy - cold leaden waves crash on the rocky shores shrouded in fog. The already sparse vegetation suffered greatly from sheep, goats, pigs and other wild animals. Now, every single pig, cat and dog has been removed from the islands on which tuateria populations have remained, and the rodents have been destroyed. All these animals caused great damage to the tuatara by eating their eggs and young. Of the vertebrate animals on the islands, only reptiles and numerous seabirds remain, establishing their colonies here.

An adult male tuateria reaches a length (including tail) of 65 cm and weighs about 1 kg. Females are smaller and almost twice as light. These reptiles feed on insects, spiders, earthworms and snails. They love water, often lie in it for a long time and swim well. But the tuatara runs poorly.

Hatteria is a nocturnal animal, and unlike many other reptiles, it is active when relatively low temperatures- +6 o...+8 o C - this is another interesting feature of its biology. All vital processes in tuateria are slow, metabolism is low. There is usually about 7 seconds between two breaths, but a tuatara can remain alive without taking a single breath for an hour.

Winter time - from mid-March to mid-August - tuataria spend in burrows, hibernating. In the spring, females dig special small burrows into which, using their paws and mouth, they transfer a clutch of 8-15 eggs, each of which is about 3 cm in diameter and enclosed in a soft shell. The top of the masonry is covered with earth, grass, leaves or moss. The incubation period lasts about 15 months, that is, much longer than that of other reptiles.

The tuatara grows slowly and reaches sexual maturity no earlier than 20 years. That is why we can assume that she is one of the outstanding long-livers of the animal world. It is possible that some males are over 100 years old.

What else is this animal famous for? Hatteria is one of the few reptiles with a real voice. Her sad, hoarse cries can be heard on foggy nights or when someone is bothering her.

Another one amazing feature Tuatara live together with gray petrels, which nest on the islands in self-dug burrows. Hatteria often settles in these holes, despite the presence of birds there, and sometimes, apparently, destroys their nests - judging by the finds of chicks with their heads bitten off. So such a neighborhood, apparently, does not give the petrels much joy, although usually birds and reptiles coexist quite peacefully - the hatteria prefers other prey, which it goes in search of at night, and in the daytime the petrels fly to the sea for fish. When the birds migrate, the hatteria hibernates.

The total number of living tuataria is now about 100,000 individuals. The largest colony is located on Stephens Island in the Cook Strait - 50,000 tuatara live there on an area of ​​3 km 2 - an average of 480 individuals per 1 hectare. On small islands with an area of ​​less than 10 hectares, the population of tuateria does not exceed 5,000 individuals. The New Zealand government has long recognized the value of this amazing reptile for science, and there has been a strict conservation regime on the islands for about 100 years. You can visit them only with special permission and strict liability is established for violators. In addition, tuatara are successfully bred at the Sydney Zoo in Australia.

Hatterias are not eaten, and their skins have no commercial demand. They live on remote islands, where there are no people or predators, and are well adapted to the conditions existing there. So, apparently, nothing threatens the survival of these unique reptiles at present. They can easily while away their days on secluded islands, to the delight of biologists who, among other things, are trying to find out the reasons why the hatteria did not disappear in those distant times when all its relatives became extinct.

Perhaps we can learn from the people of New Zealand how to protect our natural resources. As Gerald Durrell wrote, “Ask any New Zealander why they protect the tuateria. And they will consider your question simply inappropriate and will say that, firstly, this is a one-of-a-kind creature, secondly, zoologists are not indifferent to it, and, thirdly, if it disappears, it will disappear forever.” Can you imagine such a response from a Russian resident to the question of why protect, say, the Caucasian cross? So I can’t. Maybe that’s why we don’t live like we do in New Zealand?

V.V. Bobrov

Hatteria is endangered relict species and protected by law, they are kept in captivity only in a few zoos.

Until 1989, it was believed that there was only one species of these reptiles, but Victoria University (Wellington) professor Charles Dougherty discovered that there are actually two of them - the hatteria ( ) and Brother Island tuatara ( Sphenodon guntheri).

The tuatara, better known as the tuatara, is the only remaining beaked reptile in the world. Perhaps its existence is not so well known to ordinary people, but in the scientific world, information about the last living creature of the prehistoric fauna has spread far beyond its habitat. They are the last witnesses of the animal world of the age of dinosaurs and a real treasure of Polynesia.

They represent a large and ancient lineage of vertebrates and are a key link to the ancestors that evolved into the dinosaurs. modern reptiles, birds and mammals. Once widespread on the Gondwanaland continent, the species has become extinct everywhere except for a small group living on a few New Zealand islands.


The oldest fossilized tuataras are found in rocks Jurassic period, in sand dunes, peat bogs and caves. Fossil evidence suggests that the tuatara was once distributed throughout the country. The first researchers classified the tuatara as a lizard, but in 1867, Dr. Gunther from the British Museum, studying its skeleton in detail, proposed a different classification, which was accepted by everyone scientists world. They became the extreme taxon of their group on the evolutionary tree, intriguing for their mixed properties. Having the skull structure and vestigial reproductive organ of birds, the ears of turtles and the brain of amphibians, their hearts and lungs were formed before the appearance of living animals. The presence of a “third eye”, located in the upper part of the skull, in the form of a scaly growth, is also striking.

Features of hutteria

Cold-blooded and slow-moving, ancient tuataria are a kind of chubby-cheeked, long-tailed iguana, with spines on their neck, back and tail, as long as a human forearm. Their name translated from the Maori language means “spikes on the back.”


The tuatara has one row of teeth on the lower jaw and two rows on the upper jaw. The upper jaw is rigidly attached to the skull. Their teeth are an extension of the jaw bones. When they wear out, they are not replaced, but they also do not fall out. This distinctive unique feature affects the mechanism of food absorption.

Newborn individuals have a horny, non-calcified, so-called egg tooth, which is provided by nature to facilitate emergence from the egg. Soon after birth, this tooth falls out. Unlike lizards, the vertebrae of the hatteria are more reminiscent of the vertebral bones of fish and some other amphibians. Their bony ribs are more typical of crocodiles than lizards. Males do not have a sexual organ. Tuatara is one of the least studied and most ancient animals.


Hatterias reach their peak activity when their body temperature is 12-17 degrees Celsius. This is a record among reptiles for minimum temperature, suitable for life. Perhaps this is the reason why the species was able to survive in temperate climate New Zealand. Other reptiles are active when their body temperature is between 25 and 38 degrees Celsius. Another remarkable feature of tuataras is their breathing rate. They breathe air only once an hour. The species does not need to drink water.

Lifestyle and habits of tuataria

Tuatara are mostly active at night, but sometimes come out during the day to bask in the sun. They live in burrows, which they sometimes share with seabirds. The house is located underground in holes that form labyrinths of tunnels. In the spring, they happen to feed on bird eggs and newly hatched chicks.

Their main food is beetles, worms, centipedes and spiders; they can feast on lizards, frogs, and other small invertebrates. They go out to eat mainly at night. It happens that adult tuataria eat their tiny offspring. Older individuals should eat soft foods, as do many older individuals.


They're like sprinters short distances, can move with maximum speed not for long, after which, exhausted, they should stop and rest. The heart rate is only six to eight times per minute, and they can move without eating. In winter, they fall into a state similar to lethargy and so deeply that they seem dead. Tuatara are often referred to as living or relict "fossils", along with coelacanth fish, horseshoe crabs, nautiluses and the ginkgo tree.

Like many other New Zealand animals, the tuatara is a long-lived animal. They reach reproductive maturity after about 15 years of life. Reproductive capacity persists for many decades. Females are able to lay eggs only once every few years. The maximum lifespan has not been precisely studied. Some living individuals have reached 80 summer age in captivity, under the constant supervision of specialists, but still look quite energetic.

Appearance

Hatterias are quite muscular, have sharp claws and partially webbed feet, and can swim well. In case of danger, they hit with their tail, bite and scratch. Males can weigh more than a kilogram, females rarely exceed five hundred grams. They grow faster in captivity than in the wild. Tuatara are unusual in that they like cool weather. They do not survive temperatures above 25 degrees Celsius, but survive temperatures below five degrees by taking refuge in burrows. Most activity is seen at temperatures ranging from seven to twenty-two degrees Celsius, and most reptiles hibernate at such low temperatures.


The male has a distinctive crest of spines along his neck and back, which he can deploy to attract females or fight enemies. Tuatara colors range from olive green, brown to orange-red. Coloring may change over the course of life. They molt once a year.

Reproduction of tuatara

Sexual maturity is reached at approximately 20 years of age. Reproduction occurs slowly. After mating in the summer, females lay eggs only the following spring. Eggs burrow into the soil. Where they remain until they are born for 13-14 months. A total of 6 to 10 eggs are laid.


Hatterias have an unusual feature. Sex of offspring depends on temperature environment. If the soil temperature is relatively cool, not only will the egg stay in the ground longer, but a female egg will be more likely to emerge. In order for a male individual to be born, it takes enough warm temperature. After a little over a year, the children hatch and must take care of themselves. Newly hatched individuals, no larger than a paperclip. It may take two decades before the cub matures, unless during this time it becomes someone's prey.

Endemic to New Zealand

Tuatara live only in New Zealand and the nearby Cook Islands. All reptiles in New Zealand are protected by law. They feature in Maori legends and are believed by some tribes to be repositories of knowledge. They were almost completely wiped out by the rats that arrived on the isolated continent with the first Polynesian explorers. Rats also drove the hatteria from the mainland to the remote islands. Today, tuataras persist on only 35 small, predator-free islands.

Currently, the tuatara lives on approximately 35 islands. Seven of these islands are in the Cook Strait region - between Wellington at the southern tip of the North Island and Marlborough-Nelson at the tip South Island. In total there are about 45,500 animals. Another 10,000 tuatara are found around the North Island - near Auckland, Northland, the Coromandel Peninsula and the Bay of Plenty.


Reasons for the decline in tuatara numbers

Although a small amount of Tuatara are found in the wild and quite successful captive breeding programs have been launched, but the species remains under threat of extinction.
Before people appeared, the only ones natural enemies there were large birds.

When Polynesian settlers arrived in New Zealand in 1250-1300, they brought with them the kiore, the small Pacific rat. Kiore have become the main threat to the population. By the mid-19th century, when the first European inhabitants settled here, the tuatara on the mainland had already become almost extinct.


At that time, the Hatteria managed to find temporary shelter on some islands, but they were eventually overrun by rats and other predators that arrived with the European settlers. Since an adult can reach a length of 75 centimeters, it was the young specimens that were subjected to most at risk from predators such as cats, dogs, ferrets, rats and possums.

Already in 1895, the tuatara were under legal protection, but their numbers continued to decline rapidly. Hundreds of copies were sent abroad to museums and private collections. Poaching is still a problem.

Predator Control Measures

In the mid-eighties of the last century, the security service wildlife and its successor, the Department for the Conservation of Endangered Species, began developing ways to remove rats from the islands. In addition to predator eradication, other measures to protect the tuatara have been introduced, such as egg collection and incubation, captive breeding programs, and relocation to rat-free islands.

The Maori experience of Hauturu Island, commonly known as the Little Barrier, which is located in the Hauraki Gulf between Auckland and the Coromandel Peninsula, is wonderful example saving rare animals from extinction through conservation initiatives. In 1991, after the launch of the program, no traces of animals were found on the island. After 14 years, researchers found eight adults. By providing them with a safe habitat and breeding offspring in incubators, residents returned these wonderful animals to the wild.


Nowadays New Zealand spends huge amounts of money fighting mammals that have artificially inhabited the islands. The main endemic animal pests are rats and possums. The government has set itself an ambitious goal: to clear the country of imported predators by 2050. At the moment, the project is at the stage of developing the technologies necessary for its implementation. At the moment, according to the Ministry of Nature Protection, about a hundred islands have been cleared of the countless predators that have captured them. National and regional pest control programs are in place. The cost of making and installing traps, poisoning and developing new technologies amounts to more than $70 million a year. Employees of the Department for the Conservation of Endangered Animals actively cooperate with universities, zoos and others government agencies on issues of protecting the remaining population.

There are four main strategies for preserving them:

  • Destruction of pests on habitat islands;
  • Egg incubation: wild collection and controlled laboratory hatching;
  • Raising young animals: young individuals are raised in special enclosures until adulthood;
  • Reintroduction: Individuals are transported to a new area to establish a new population or help restore an existing one.

The idea of ​​settling more southern regions is one of the most effective. The wild tuatara habitat on the small islands to the north is vulnerable to the impacts of climate change, rising sea levels, rising temperatures and extreme weather events. weather conditions. The Tuatara have a long future ahead if humane and effective ways destroying their enemies.


Until 1998, tuatara could only be found in reserves on islands that were closed to the public. As an experiment, life observation was possible on Matthew Island in Wellington Harbor and on an island near Auckland. People rushed to see with their own eyes the results of the work of successful environmental projects for population restoration. Since 2007, they have been available to watch at Karori Wildlife Sanctuary, 10 minutes from Wellington city centre.

The tuatara is the symbol of New Zealand. They are represented in paintings and immortalized in sculptures, postage stamps and coins. From 1967 to 2006, a lizard sitting on a rocky shore was minted on the nickel.

Then you can place an order on the Internet resource www.snol.ru. I am sure you will be satisfied with the price-quality ratio and the level of after-sales service!

Hatteria is a reptile that has three eyes. She lives in New Zealand. Scientists have found that they began to exist about two hundred million years ago and have not succumbed to changes throughout their existence on the planet.

Hatteria

An interesting fact is that tuataria were able to survive in such difficult conditions. living conditions survive the most big creatures on Earth - dinosaurs.

James Cook is considered the discoverer of the tuatteria, who saw the tuatteria during his trip to New Zealand. Looking at the tuatteria for the first time, it may seem that it is an ordinary lizard. The length of the hatteria is 65-75 centimeters, including the tail. The weight of the tuateria does not exceed 1 kilogram 300 grams.

On average, she lives 60 years, but sometimes her age reached 100 years. The readiness to engage in sexual intercourse appears in tuaterias upon reaching 15-20 years of age. Mating occurs at intervals of four years. Tutteria babies are born almost 12-15 months later. Due to such a long period of reproduction of their own kind, hatteria are decreasing in number too quickly.

Particular activity was observed at night. The tuateria has a superbly developed parietal eye. This part of the body has a connection with the appearance and functions of the pineal gland. The reptile has an olive-green or greenish-gray color, and yellowish spots are visible on its sides. There is a ridge on the back, parts of which resemble triangles. That is why the reptile is sometimes called “spiny.”

Hatteria cannot be classified as a lizard due to the structure of its head. Therefore, scientists in the 19th century. They proposed to separate them into a separate order - the beak-headed ones. The thing is that reptiles have a unique skull structure. The uniqueness lies in the fact that in young tuataria the upper jaw, upward skull and palate move in relation to the brain case. In scientific circles this is called cranial kineticism. That is why the upper part of the tuateria's head tends to tilt down and change position to the opposite during the movements of the rest of the skull.

This skill was passed on to reptiles by lobe-finned fish, which are their ancient ancestors. It should be noted that kineticism is also inherent in some species of lizards and snakes. In addition, today the number of hatterias on the planet is sharply decreasing. Due to this this type reptiles are subject to special control and protection.

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  • Class: Reptilia = Reptiles
  • Order: Rhynchocephalia Haeckel, 1868 = Beak-headed, proboscis-headed
  • Family: Sphenodontidae Cope, 1870 = Wedge-toothed
  • Genus: Sphenodon Gray, 1831 = Hatteria, tuatara

Species: Sphenodon punctatus = Tautara, hatteria: structural features

Hatteria is, at first glance, a large, impressive-looking lizard. The scaly skin of the tuataria is painted in a dull olive-green or greenish-gray color, and there are small and larger yellow spots on the sides of the body and limbs. And there are short, strong paws with claws. From the back of the head, along the back and tail, stretches a low crest consisting of flat triangular vertical scale plates, like those of agamas and iguanas. Therefore, the local name for tuatara is derived from the Maori word meaning “spiny.” The body of the tuataria ends in a long tail.

Pupils big eyes, located on the sides of the head, in the form of a vertical slit. The hatteria does not have eardrums or middle ear cavities. On the upper side of the head, somewhat behind the eyes, under the skin, a peculiar organ is hidden - the so-called parietal eye. In adult tuataria, it is not outwardly noticeable, but in young ones that have recently hatched from eggs (six months old), it looks like an area of ​​the skin surface not covered with scales.

The parietal eye of the hatteria is a bubble-shaped organ that has a layer of light-sensitive cells and something like a lens. The function of the parietal eye (also present in some lizards) is not yet fully understood. In any case, it has photosensitivity, but most likely does not serve as an organ of vision, but perceives only the degree of illumination, depending on the level solar radiation. Such an organ helps the animal regulate body temperature by choosing a place and posture in relation to the sun's rays. There is a hypothesis that through this eye young animals receive vitamin D through ultra-violet rays, which helps them develop and grow faster. Already at the age of 4-6 months it becomes overgrown with scales.

The skeleton of the hatteria combines a very primitive basic structure with some features of specialization. In the temporal region of the skull there are two pairs of pits - the upper and lateral temporal ones, from the edges of which the jaw muscles begin (diapsid type). The upper and lower fossa of each side of the skull are separated by the bony superior temporal arch, formed by the postorbital and squamosal bones, the lower temporal fossa is limited from below by the lower temporal arch, which in the tuateria is formed by the zygomatic bone. This diapsid structure of the temporal region of the skull was also present in the ancestors of modern lizards and snakes; it is also preserved in crocodiles and was present in many fossil reptiles, united on this basis into the diapsid group (possibly related by distant kinship).

For a long time the hatteria was looked upon as a representative of these primitive forms that has survived to this day. However, although the hatteria did retain many primitive features, the beak-headed reptiles are by no means the ancestors of any other groups of reptiles, but represent a blind lateral branch of the primitive diapsid reptiles (eosuchians). An interesting feature has been preserved in the hatteria skull: the upper jaw, palate and roof of the skull are movable relative to the braincase (at least in young individuals). This phenomenon is called cranial kineticism. Thanks to kineticism, the anterior end of the upper jaw can be bent down to some extent and retracted back with simultaneous complex movements other elements of the skull. Terrestrial vertebrates inherited the kineticism of the skull from their ancestors - lobe-finned fish.

Among scientists there is currently no consensus on the functions of cranial kineticism. Probably, kineticism serves to better retain the captured prey in the jaws of the predator, but at the same time it can also provide shock absorption of the jaws and jerks of the prey when these shocks are transmitted to the braincase. Among modern reptiles, except for the tuataria, more complex and effective forms Lizards and snakes have skull kineticism. The direct articulation of the vomer and pterygoid bones is primitive in the hatteria skull. Traits of high specialization are loss of the lacrimal and superotemporal bones.

The teeth of the tuateria are simple wedge-shaped; they grow to the upper edge of the lower and lower edge of the upper jaws (acrodont). In adult animals, the teeth wear down so much that the bite is made by the very edges of the jaws, the covers of which become keratinized. The second row of teeth is located on the palatine bone; the teeth of the lower jaw fit between these two rows of teeth. The vertebrae retain a primitive biconcave (amphicoelous) structure. The lost tail is regenerated. In addition to the usual ribs, which bear backward-directed uncinate processes, there is also a series of so-called abdominal ribs located between the sternum and pelvis under the skin. Among modern reptiles, both hook-shaped processes and abdominal ribs, except for tuateria, are preserved only in crocodiles.

In the shoulder girdle, in addition to the scapula and coracoid, there are clavicles and an unpaired interclavicle. Internal structure tuatteria are close to those of lizards, differing in some primitive features. So, in the heart there is a venous sinus (sinus), into which the vena cava flows. This section is present in the heart of fish (where the cardinal veins or ducts of Cuvier flow into it) and in the heart of amphibians, but is absent as special department hearts in other modern reptiles. The cloaca of the tuateria, like that of lizards, has the appearance of a transverse slit.

If you think that tuatara or tuatara (lat. Sphenodon punctatus ) is just another one of the lizards, you are deeply mistaken! In fact, it is so unusual that a separate order was created for it back in the 19th century - beak-headed (lat. Phynchocephalia).

From large lizards The tuatara is distinguished primarily by the structure of its unusual skull. The upper jaw, palate and roof of the skull of young tuataria are mobile in relation to the braincase. Those. during complex movements, the anterior tip of the upper jaw bends down and is slightly retracted.

In addition, tuataras boast the presence of a third (parietal) eye located in the back of the head. Just don't try to find it in photographs of adults! The fact is that this amazing organ is clearly visible only in newborn babies. It is a bare speck, surrounded on all sides by scales. The third eye is equipped with a lens and light-sensitive cells, but the organ does not have muscles that could help focus its position. With age, the eye becomes covered with skin.

Its exact purpose, unfortunately, is still not known. It is assumed that it is needed to determine the level of light and ambient air temperature so that the tuatara can control its exposure to the sun. She, like all reptiles, loves to bask on warm rocks.

The tuateria lives on the small islands of New Zealand. Previously, these unusual reptiles were found on the two main islands - North and South. However, they were destroyed by the Maori tribes who settled here in the 16th century. Today, tuataras are protected as an endangered species. For their sake, all feral dogs, cats and pigs were evicted from the islands, and rodents were also destroyed. Access to these islands is only possible with special permission. Violators will face no less than imprisonment. This is how they take care of this strange reptile!

Such concern is not surprising, given that the tuateria is oldest species, which managed to maintain its original appearance since its appearance on our planet. And this happened about 200 million years ago. A real living fossil!

The male's body length including tail can reach 65 cm and weighs about 1 kg. The body length of females is somewhat shorter, and their weight is almost half that. A small ridge runs along the back, which consists of triangular plates. It was he who gave the name to the species: “tuatara” means “spiny”.

Hatterias settle directly in the nests of gray petrels. During the day they hide here from predators while the birds fly around in search of food, and at night they themselves go after prey, giving way to the owners of the nest. They do not pay very well for “hospitality”: during the breeding season of birds, tuatara sometimes eat their chicks. Although much more often they feed on insects, snails and spiders.

Hatterias live for about 100 years. Their metabolism is so slow and their life processes are so slow that they take a very long time to develop. For example, pregnancy in females lasts from 8 to 10 months, and the incubation period of laid eggs lasts as long as 15 months. Tuatara reach sexual maturity only at 15 or even 20 years of age. In general, they are in no hurry. Maybe this is the secret of longevity?