Deserts and semi-deserts are waterless, dry areas of the planet where no more than 25 cm of precipitation falls per year. The most important factor their formation is the wind. However, it is not observed in all deserts hot weather, some of them, on the contrary, are considered the coldest regions of the Earth. Representatives of flora and fauna have adapted differently to harsh conditions these areas.

How do deserts and semi-deserts arise?

There are many reasons why deserts arise. For example, there is little precipitation in the city because it is located at the foot of the mountains, which cover it from rain with their ridges.

Ice deserts formed for other reasons. In Antarctica and the Arctic, the bulk of the snow falls on the coast; snow clouds practically do not reach the interior regions. Precipitation levels generally vary greatly; one snowfall, for example, can result in a year's worth of precipitation. Such snow deposits form over hundreds of years.

Hot deserts have a wide variety of topography. Only some of them are completely covered with sand. The surface of most is strewn with pebbles, stones and other different breeds. Deserts are almost completely open to weathering. Strong gusts of wind pick up fragments of small stones and hit them against the rocks.

In sandy deserts, the wind moves sand across an area, creating wave-like deposits called dunes. The most common type of dunes is dunes. Sometimes their height can reach 30 meters. Ridge dunes can be up to 100 meters high and extend for 100 km.

Temperature

The climate of deserts and semi-deserts is quite diverse. In some regions, daytime temperatures can reach 52 o C. This phenomenon is associated with the absence of clouds in the atmosphere, thus nothing saves the surface from direct sun rays. At night, the temperature drops significantly, which is again explained by the absence of clouds that can trap the heat emitted by the surface.

In hot deserts, rain is a rare occurrence, but sometimes heavy downpours occur here. After rain, water does not soak into the ground, but quickly flows from the surface, washing away particles of soil and stones into dry channels called wadis.

Location of deserts and semi-deserts

On continents that are located in northern latitudes, there are deserts and semi-deserts of the subtropical and sometimes tropical ones are also found - in the Indo-Gangetic lowland, in Arabia, in Mexico, in the southwestern United States. In Eurasia, extratropical desert areas are located in the Central Asian and South Kazakh plains, in the basin Central Asia and in the Western Asian highlands. Central Asian desert formations are characterized by sharp continental climate.

In the southern hemisphere, deserts and semi-deserts are less common. Here are located such desert and semi-desert formations as the Namib, Atacama, desert formations on the coast of Peru and Venezuela, Victoria, Kalahari, Gibson Desert, Simpson, Gran Chaco, Patagonia, Great Sandy Desert and Karoo semi-desert in southwest Africa.

Polar deserts are located on the mainland islands of the periglacial regions of Eurasia, on the islands of the Canadian archipelago, in northern Greenland.

Animals

Over the many years of existence in such areas, animals of deserts and semi-deserts have managed to adapt to harsh climatic conditions. They hide from cold and heat in underground burrows and feed mainly on underground parts of plants. Among the fauna there are many species of carnivores: fennec fox, pumas, coyotes and even tigers. The climate of deserts and semi-deserts has contributed to the fact that many animals have developed a well-developed thermoregulation system. Some desert inhabitants can withstand fluid loss of up to a third of their weight (for example, geckos, camels), and among invertebrates there are species that are capable of losing water up to two-thirds of their weight.

IN North America and Asia there are a lot of reptiles, especially many lizards. Snakes are also quite common: ephas, various poisonous snakes, boas. Large animals include saiga, wild ass, camels, and pronghorn, which recently disappeared (it can still be found in captivity).

Animals of the desert and semi-desert of Russia are a wide variety of unique representatives of the fauna. The desert regions of the country are inhabited by sand hares, hedgehogs, kulan, jaiman, and poisonous snakes. In the deserts that are located in Russia, you can also find 2 types of spiders - karakurt and tarantula.

They live in polar deserts polar bear, musk ox, arctic fox and some species of birds.

Vegetation

If we talk about vegetation, then in deserts and semi-deserts there are various cacti, hard-leaved grasses, psammophyte shrubs, ephedra, acacias, saxauls, soap palm, edible lichen and others.

Deserts and semi-deserts: soil

The soil, as a rule, is poorly developed; its composition is dominated by water-soluble salts. Among them, ancient alluvial and loess-like deposits predominate, which are reworked by winds. Gray-brown soil is typical for elevated flat areas. Deserts are also characterized by salt marshes, that is, soils that contain about 1% of easily soluble salts. In addition to deserts, salt marshes are also found in steppes and semi-deserts. Groundwater, which contains salts, upon reaching the soil surface is deposited into the soil. top layer, resulting in soil salinization.

Completely different characteristics are characteristic of such climatic zones as subtropical deserts and semi-deserts. The soil in these regions has a specific orange and brick-red color. Due to its shades, it received the corresponding names - red soils and yellow soils. IN subtropical zone in northern Africa and in South and North America there are deserts where gray soils have formed. In some tropical desert formations, red-yellow soils have developed.

Natural and semi-deserts are a huge variety of landscapes, climatic conditions, flora and fauna. Despite the harsh and cruel nature of the deserts, these regions have become home to many species of plants and animals.

All Australian deserts lie within the Central Australian region of the Australian Floristic Kingdom. Although in terms of species richness and level of endemism desert flora Australia is significantly inferior to the flora of western and northeastern regions this continent, however, compared to other desert regions globe it stands out both in the number of species (more than 2 thousand) and in the abundance of endemics. Species endemism here reaches 90%: there are 85 endemic genera, of which 20 are in the Asteraceae family, 15 in the Chenopoaceae family, and 12 in the Cruciferae family.

Among the endemic genera there are also background desert grasses - Mitchell's grass and triodia. A large number of species are represented by the families of legumes, myrtaceae, proteaceae and asteraceae. Significant species diversity is demonstrated by the genera Eucalyptus, Acacia, Proteaceae - Grevillea and Hakea. In the very center of the continent, in the gorge of the deserted MacDonnell Mountains, narrow-area endemics have been preserved: the low-growing Liviston palm and Macrozamia from the cycads.

Even some types of orchids live in deserts - ephemerals that germinate and bloom only in short period after the rains. Sundews also penetrate here. The depressions between the ridges and the lower part of the slopes of the ridges are overgrown with clumps of the prickly grass triodia. Upper part The slopes and ridges of dune ridges are almost completely devoid of vegetation, only individual curls of the prickly grass Zygochloa settle on the loose sand. In interbarchan depressions and on flat sandy plains, a sparse tree stand of casuarina, individual specimens of eucalyptus, and veinless acacia is formed. The shrub layer is formed by Proteaceae - these are Hakea and several types of Grevillea.

In slightly saline areas in depressions, saltwort, ragodia and euhilena appear. After the rains, the interridge depressions and lower parts of the slopes are covered with colorful ephemerals and ephemeroids. IN northern regions on the sands of the Simpson and Great Sandy Deserts species composition the background grasses change somewhat: other species of triodia, plectrahne and shuttlebeard, dominate there; the diversity and species composition of acacias and other shrubs becomes greater. Along the channels of temporary waters, gallery forests of several species of large eucalyptus trees form. The eastern edges of the Great Victoria Desert are occupied by sclerophyllous mum scrub scrub. The southwestern Great Victoria Desert is dominated by low-growing eucalypts; The grass layer is formed by kangaroo grass, feather grass species and others.

The arid areas of Australia are very sparsely populated, but the vegetation is used for grazing.

Climate

In the tropical climatic zone, occupying the territory between the 20th and 30th parallel in the desert zone, a tropical continental desert climate is formed. A subtropical continental climate is common in southern Australia adjacent to the Great Australian Bight. These are the marginal parts of the Great Victoria Desert. Therefore, in the summer period, from December to February, average temperatures reach 30 ° C, and sometimes higher, and in winter (July - August) they drop to an average of 15-18 ° C. In some years, the entire summer period temperatures can reach 40° C, a winter at night in the vicinity of the tropics it drops to 0° C and below. The amount and territorial distribution of precipitation is determined by the direction and nature of the winds.

The main source of moisture is the "dry" southeast trade winds, since most of the moisture is retained by the mountain ranges of Eastern Australia. The central and western parts of the country, corresponding to about half the area, receive an average of about 250-300 mm of precipitation per year. The Simpson Desert receives the least amount of precipitation, from 100 to 150 mm per year. The precipitation season in the northern half of the continent, where monsoon winds prevail, is confined to summer period, and, in its southern part, dry conditions prevail during this period. It should be noted that the number winter precipitation in the southern half it decreases as you move deeper into the continent, rarely reaching 28° S. In turn, summer precipitation in the northern half, having the same trend, does not extend south of the tropic. Thus, in the zone between the tropics and 28° S. latitude. there is a belt of aridity.

Australia is characterized by excessive variability in average annual precipitation and uneven distribution throughout the year. The presence of long dry periods and high average annual temperatures, dominant over a large part of the continent, cause high annual evaporation values. In the central part of the continent they are 2000-2200 mm, decreasing towards its marginal parts. The surface waters of the continent are extremely poor and extremely unevenly distributed throughout the territory. This especially applies to the desert western and central regions of Australia, which are practically drainless, but make up 50% of the continent's area.

May 12, 2013

The presence of natural zones on the mainland and their location directly depend on climatic zones. Given that Australia is considered the driest continent, it becomes clear that there simply cannot be much diversity here. But the natural areas of Australia have an extremely unique flora and fauna.

Lots of deserts and few forests

On the smallest continent, zoning is clearly visible. This is due to the prevailing flat nature of the relief. Natural areas Australia gradually replace each other in the meridional direction following changes in temperature and precipitation.

The southern tropic crosses the continent almost in the middle, and most of its territory is in the hot tropical climate zone, which makes the climate arid. In terms of annual precipitation, Australia ranks among all continents. last place. Most of its territory receives only 250 mm of precipitation throughout the year. In many areas of the continent, not a drop of rain falls for several years.

Australia, whose natural zones divide the continent into three parts, has several zones in the east and west, stretched along the coast, where the amount of precipitation is noticeably higher. The mainland is in first place in terms of the relative area of ​​desert areas and in last place in terms of forest area. In addition, only 2% of Australia's forestlands are of industrial importance.

Features of natural areas

Savannas and open forests are located in the subequatorial climate zone. The vegetation is dominated by grasses, among which grow acacias, eucalyptus trees, and bottle trees.

In the east of the continent, in conditions of sufficient moisture, there are such natural zones of Australia as tropical rainforests. Among palm trees, ficus and tree ferns live marsupial anteaters, wombats, kangaroos.

Australia's natural areas differ from similar areas on other continents. For example, semi-deserts and tropical deserts occupy huge areas on the mainland - almost 44% of its territory. In the Australian deserts you can find unusual thickets of dry thorny bushes called scrubs. Semi-desert areas overgrown with tough cereal plants and shrubs are used as pasture for sheep. There are also large sandy deserts, which differ from the deserts of other continents in that they do not have oases.

In the southeastern part and southwest of the continent there are subtropical forests, in which eucalyptus and evergreen beech grow.

The originality of the organic world

The flora of Australia, thanks to its long isolation from other continents, has large number endemic plants. Almost 75% of them can only be seen here and nowhere else. More than 600 species of eucalyptus, 490 species of acacia and 25 species of casaurines are found on the mainland.

The fauna is even more peculiar. Among animals, endemics account for almost 90%. Only in Australia can you find mammals that disappeared on other continents a long time ago, for example, the echidna and the platypus - ancient primitive animals.

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Miscellaneous
Miscellaneous

It does not have a single sea, there are not even large stable lakes and rivers. Particularly deserted are the central and Western Australia. Here, no more than 250 mm of water reaches the surface of the earth per year, yet the prevailing part of the deserts is covered with vegetation. The predominant plant species are triode and acacia grasses. Sometimes these areas are used for grazing. However, animals require very large territories, because... the vegetation is sparse and not very nutritious.

Flora The deserts of Australia are quite diverse; more than 2 thousand species of endemics are found here. Eucalyptus trees are very diverse and common. In places with a large number food, you can meet animals. The largest is the kangaroo. In general, marsupials are characteristic of Australia. The desert is home to marsupial shrews, moles, badgers, martens, etc. Many deserts are completely “clad” with sand dunes, although they are also supported by sparse vegetation. Only rocky deserts are practically lifeless. Moving sand dunes are very rare.

Rivers and lakes fill with water sporadically - during rare rains. The largest lake is Air, is located in the desert. It is replenished with water very rarely; even during the rainy season, the water of the creeks (temporary rivers) does not always reach it. Great Desert Victoria a rather harsh place, but still it became native to some tribes (Koghara, Mirning). There are no economic activities in the desert. Maybe that's why they arranged it here biosphere reserve. The Simpson Desert is quite arid, although it does have a number of salt marsh lakes. In addition, it is rich in artesian waters, but they do not contribute to the development of vegetation. The surface of the desert consists of sandy ridges interspersed with rocky and rubble plains.

Big sandy desert

With an area of ​​360 thousand square meters. km is located in the northwestern part of the continent, and extends in a wide strip (over 1300 km) from the coast Indian Ocean to the MacDonnell Ranges. The desert surface is elevated above sea level to a height of 500-700 m. Typical shape The relief is latitudinal sand ridges. The amount of precipitation in the desert varies from 250 mm in the south to 400 mm in the north. There are no permanent watercourses, although there are many other dry riverbeds along the periphery of the desert.

Great Australian Desert

The Aborigines who moved to Australia 50 thousand years ago are directly responsible for the fact that most of the country turned into desert. According to CNN , recent studies conducted by scientists from the Green Continent and the United States have shown that the cause of the natural disaster that destroyed most of the flora in the country could have been fires lit by the aborigines. “The fire-making practices of Australia’s ancient inhabitants may have had consequences that changed the country’s climate and landscape,” says Gifford MILLER, a fellow at the University of Colorado in the US. Gifford Miller).

Geological studies have shown that 125 thousand years ago Australia's climate was much wetter than it is today. Fires caused by Aboriginal fires could have sharply reduced the area of ​​forests, thereby changing the concentration of water vapor in the atmosphere. It became insufficient for cloud formation, and the climate became drier. Similar assumptions are confirmed by computer modeling of variations in climate conditions on the continent. Paleontologists also argue that the animals that inhabited most of Australia in ancient times were better suited to living in forests rather than in deserts and semi-deserts. Scientists believe that it was humans who were responsible for the fact that 85 percent of the species of large animals, such as eight-meter lizards and car-sized turtles, had already become extinct in Australia by the time Europeans arrived.

Currently, deserts, some of which are devoid of any vegetation at all, cover more than half of Australia. A significant part of the Australian deserts, namely those that have occupied western part continent, are located at some elevation - on a huge plateau approximately 200 meters above sea level. Some deserts rise even higher, up to 600 meters. Australia has several large sand and pebble deserts, some are purely sandy, but most are covered with rubble and pebbles. All deserts of Australia are in approximately equal weather conditions - there is very little precipitation here, on average 130-160 millimeters per year. Temperature all year round plus - in January about +30 Celsius, in July at least +10.

Great Victoria Desert

Climatic conditions Australia due to her geographical location, orographic features, huge water area Pacific Ocean and the proximity of the Asian continent. From three climatic zones southern hemisphere Australia's deserts are located in two categories: tropical and subtropical, with most of them occupying the latter zone. In the tropical climate zone, which occupies the territory between the 20th and 30th parallel in the desert zone, a tropical continental desert climate is formed.

A subtropical continental climate is common in southern Australia adjacent to the Great Australian Bight. These are the marginal parts of the Great Victoria Desert. Therefore, in the summer, from December to February, average temperatures reach 30°C, and sometimes higher, and in winter (July - August) they drop to an average of 15-18°C. In some years, the entire summer period can reach 40°C, while winter nights in the vicinity of the tropics drop to 0°C and below. The amount and territorial distribution of precipitation is determined by the direction and nature of the winds. The main source of moisture is the "dry" southeast trade winds, since most of the moisture is retained by the mountain ranges of Eastern Australia.

The central and western parts of the country, corresponding to about half the area, receive an average of about 250-300 mm of precipitation per year. The Simpson Desert receives the least amount of precipitation, from 100 to 150 mm per year. The precipitation season in the northern half of the continent, where monsoon winds prevail, is confined to the summer period, and in the southern part, dry conditions prevail during this period. It should be noted that the amount of winter precipitation in the southern half decreases as one moves inland, rarely reaching 28° S. In turn, summer precipitation in the northern half, having the same trend, does not extend south of the tropic. Thus, in the zone between the tropics and 28° S. latitude. there is a belt of aridity.

Australia is characterized by excessive variability in average annual precipitation and uneven distribution throughout the year. The presence of long dry periods and high average annual temperatures prevailing over large parts of the continent cause high annual evaporation values. In the central part of the continent they are 2000-2200 mm, decreasing towards its marginal parts. The surface waters of the continent are extremely poor and extremely unevenly distributed throughout the territory. This especially applies to the desert western and central regions of Australia, which are practically drainless, but make up 50% of the continent's area. Australia's hydrographic network is represented by temporary drying watercourses (creeks). The drainage of Australia's desert rivers belongs partly to the Indian Ocean basin and the Lake Eyre basin.

The continent's hydrographic network is supplemented by lakes, of which there are about 800, with a significant part of them located in deserts. The most large lakes– Eyre, Torrens, Carnegie and others are salt marshes or dried-out basins covered with a thick layer of salts. The lack of surface water is compensated by wealth groundwater. A number of large artesian basins stand out here (the Desert Artesian Basin, the North-West Basin, the northern part of the Murray River basin and part of the large basin groundwater in Australia - the Great Artesian Basin).

The soil cover of deserts is very unique. In the northern and central regions red, red-brown and brown soils are distinguished ( characteristic features These soils are acidic, colored by iron oxides). IN southern parts In Australia, sierozem-like soils are widespread. In Western Australia, desert soils are found along the edges of drainless basins. The Great Sandy Desert and Great Victoria Desert are characterized by red sandy desert soils. In the drainless inland depressions in southwestern Australia and in the Lake Eyre basin, salt marshes and solonetzes are widely developed.

Australian deserts are landscape-wise divided into many various types, among which Australian scientists most often distinguish mountain and foothill deserts, deserts of structural plains, rocky deserts, sandy deserts, clayey deserts, and plains. Sandy deserts are the most common, occupying about 32% of the continent's area. Along with sandy deserts, rocky deserts are also widespread (they occupy about 13% of the area of ​​arid territories.

The foothill plains are an alternation of coarse rocky deserts with dry beds of small rivers. This type of desert is the source of most of the country's desert streams and has always served as habitat for Aboriginal people. Structural plain deserts occur as plateaus no more than 600 m above sea level. After sandy deserts, they are the most developed, occupying 23% of the area of ​​arid territories, confined mainly to Western Australia.

Flora of the Australian desert

All Australian deserts lie within the Central Australian region of the Australian Floristic Kingdom. Although the desert flora of Australia is significantly inferior in species richness and level of endemism to the flora of the western and northeastern regions of this continent, however, in comparison with other desert regions of the globe, it stands out both in the number of species (more than 2 thousand) and in the abundance of endemics.

Species endemism here reaches 90%: there are 85 endemic genera, of which 20 are in the Asteraceae family, 15 in the Chenopoaceae family, and 12 in the Cruciferae family. Among the endemic genera there are also background desert grasses - Mitchell's grass and triodia. A large number of species are represented by the families of legumes, myrtaceae, proteaceae and asteraceae. Significant species diversity is demonstrated by the genera Eucalyptus, Acacia, Proteaceae - Grevillea and Hakea.

In the very center of the continent, in the gorge of the deserted MacDonnell Mountains, narrow-area endemics have been preserved: the low-growing Liviston palm and Macrozamia from the cycads. Even some types of orchids - ephemeral ones that germinate and bloom only in a short period after the rains - settle in deserts. Sundews also penetrate here. The depressions between the ridges and the lower part of the slopes of the ridges are overgrown with clumps of the prickly grass triodia.

The upper part of the slopes and the ridges of dune ridges are almost completely devoid of vegetation, only individual curls of the prickly grass Zygochloa settle on the loose sand. In interbarchan depressions and on flat sandy plains, a sparse tree stand of casuarina, individual specimens of eucalyptus, and veinless acacia is formed. The shrub layer is formed by Proteaceae - these are Hakea and several types of Grevillea. In slightly saline areas in depressions, saltwort, ragodia and euhilena appear.

After the rains, the interridge depressions and lower parts of the slopes are covered with colorful ephemerals and ephemeroids. In the northern areas of the sands in the Simpson and Great Sandy Deserts, the species composition of background grasses changes somewhat: other species of triodia, plectrahne and shutterbeard dominate there; the diversity and species composition of acacias and other shrubs becomes greater. Along the channels of temporary waters, gallery forests of several species of large eucalyptus trees form. The eastern edges of the Great Victoria Desert are occupied by sclerophyllous mum scrub scrub. In the south-west of the Great Victoria Desert, low-growing trees dominate.

Ayers Rock

Ayers Rock is the oldest and largest monolithic rock on earth (about 500 million years old), rising in the middle of a flat red desert. Tourists and photographers from all over the world flock here to admire the fantastic change of colors at sunrise and sunset, when the rock passes through all shades ranging from brown-brown to intense glowing red, to gradually “cool down”, turning into a black silhouette with sunset. Ayers Rock was and remains a sacred Aboriginal rock and there are many rock carvings at its base. Excursions to such pearls also depart from here Northern Territory, like Mt. Olgas/Kata Tjuta and Kings Canyon.

The most arid central regions of the continent are occupied by the most large areas Australia. There are a variety of terrain types here, from shifting sands, salt marshes, gravelly rocky areas to thorny forests. However, two groups dominate: 1) acacia formation Mulga-scrub; 2) formation dominated by spinifex grass, or triodni. The latter dominates the most deserted central regions.

Acacia shrub and low-growing (3-5 m) tree-shrub deserts and semi-deserts are similar in nature to the dry thorny woodlands of Somalia or the Kalahari on the African continent. The northern variants of these groups, with a short summer wet period and an abundance of tall termite mounds, can also be considered as an extreme arid variant of the savannah and woodland zone. The dominant plant almost everywhere is ours - veinless acacia - and other phyllodes species. The number of eucalyptus and casuarina trees is small; they are confined to dry river beds and extensive depressions with close occurrence groundwater. The grass cover is often almost absent or represented by very sparse groups of grasses, saltworts and other leafy succulents.

The sandy areas in the center and west of the continent are covered with thickets of extremely xeromorphic hard grasses of the genus Triodia. In Queensland and New South Wales, a prickly pear cactus has proliferated and become a nuisance weed. Prickly pear was brought from South America in the 80s of the last century and settled over an area of ​​about 24 million hectares.

Unlike the Sahara and Namib, the deserts of Australia do not have significant areas of “absolute” deserts, practically free from higher plants. In drainless basins and along the shores of salt lakes, halophytic formations formed special types widespread ancient genera (solyanka, quinoa, parfolia, prutnyak, saltpeter). Schober's saltpeter also grows in the semi-deserts of Eurasia. The Nullarbor Plain adjacent to the Great Australian Bight has semi-desert vegetation that already develops in a subtropical, close to temperate, climate. It is dominated by tall (up to 1.5 m) bushes of various halophytes - representatives of the goosefoot (hodgepodge, quinoa, etc.), which are considered a good forage plant for sheep. On the plain, due to the widespread occurrence of karst phenomena, there are almost no surface water bodies.

Some botanists believe that true deserts are almost never found in Australia, and semi-deserts predominate. Indeed, the density of vegetation cover in arid regions of the continent is usually relatively large, which is associated with regular short wet season. The annual amount of precipitation is never below 100 mm, but usually it is close to 200-300 mm. In addition, in many places there is a shallow aquifer, where moisture is retained for a long time and is available to plant roots.

Animal world. In the faunal aspect, the animal world of arid internal regions Australia as a whole is a depleted version of dry savannah and open forest groups. Most species are found in both deserts and savannas, although a number of groups of animals are especially numerous in desert and semi-desert habitats. Among mammals, such typical animals include the marsupial mole, marsupial jerboa, comb-tailed marsupial mouse and comb-tailed marsupial rat. The entire central and western parts of the continent are inhabited by large red kangaroos. These animals are numerous in many places and are considered undesirable competitors for sheep. The same applies to smaller wallaby species. Of the smallest species of the kangaroo family (smaller than a rabbit), kangaroo rats are interesting for their ability to carry a “load” - an armful of grass, grasping it with their long tail. Many species of kangaroo rats widely inhabited almost the entire continent, but are now severely exterminated by introduced dogs and foxes, and are also replaced by rabbits, which colonize and destroy their original habitats. Therefore, now they are better preserved in desert areas, where the influence of introduced animals is less felt. The most common dog here is the dingo. In some areas, wild animals have multiplied dromedary camels, brought to the mainland in the last century as vehicle on expeditions.

The most famous bird of the semi-desert regions of the mainland is the emu. This is the only species (sometimes two closely related species are distinguished) of a special family related to cassowaries. Weavers and small parrots that feed on cereal seeds (including triodia) are common throughout arid regions. This is already mentioned zebra finch, budgies, as well as nymph parrots. All these species nest in hollows of dry trees. The night parrot is very typical for arid regions. This is truly a nocturnal bird. She spends most of her time on the ground; her diet is based on triodia seeds. Unlike most other parrots, the night parrot makes its nest not in hollows, but among thickets of thorny grasses.

Of the vertebrate animals, various reptiles are especially characteristic of deserts and semi-deserts, of which lizards of the agamidae, skink and monitor lizard families predominate. The Lepidopus family, characteristic of Australia, which includes snake-like lizards with reduced limbs, also has desert representatives. Among agamidae in the tropical northern regions of dry woodlands and semi-deserts there are frilled lizards, characteristic of the savannah. Species of this genus have the ability to run on two hind limbs. This method of movement was characteristic of some Mesozoic dinosaurs. Several species of bearded lizards, similar to our common agamas, live in deserts. The most original appearance of Moloch. This small, up to 20 cm, flat lizard is all covered with outgrowths and spines. Moloch's skin can absorb moisture. In its lifestyle and appearance it resembles the American desert toad-like lizards. Moloch's main source of nutrition is ants.

Skinks are mainly endemic to Australia (sometimes including New Zealand) genera, species of which live both in deserts and in other zones. There are especially many species of the endemic genus Ctenotus - small graceful lizards with smooth scales.