Birds

 Birds are feathered, winged, bipedal, endothermic, egg-laying, vertebrate animals. With around 10,000 living species, they are the most speciose class of tetrapod vertebrates. 

Scientific name: Aves Higher classification: Tetrapod Rank: Class Lower classifications: Falconiformes, Owl, Bucerotiformes, Upupiformes, More...    Birds are warm-blooded vertebrate animals that have wings, feathers, a beak, no teeth a skeleton in which many bones are fused together or are absent, and an extremely efficient,, one-way breathing system. Flying birds have strong, hollow bones and powerful flight muscles.   Most birds can fly. Birds have a very strong heart and an efficient way of breathing - these are necessary for birds to fly. Birds also use a lot of energy while flying and need to eat a lot of food to power their flight. Not all flying animals are birds; and not all birds can fly. The ability to fly has developed independently many times throughout the history of the Earth. Bats (flying mammals), pterosaurs (flying reptiles from the time of the dinosaurs), and flying insects are not birds.  Modern birds are characterised by feathers, a beak with no teeth, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a lightweight but strong skeleton. All living species of birds have wings—the now extinct flightless moa of New Zealand were the only exception. Wings are evolved forelimbs, and most bird species can fly. Flightless birds include ratites, penguins, and a number of diverse endemic island species. Birds also have unique digestive and respiratory systems that are highly adapted for flight. Some birds, especially corvids and parrots, are among the most intelligent animal species; a number of bird species have been observed manufacturing and using tools, and many social species exhibit cultural transmission of knowledge across generations.   Many species are of economic importance, mostly as sources of food acquired through hunting or farming. Some species, particularly songbirds and parrots, are popular as pets. Other uses include the harvesting of guano (droppings) for use as a fertiliser. Birds figure prominently in all aspects of human culture from religion to poetry to popular music. About 120–130 species have become extinct as a result of human activity since the 17th century, and hundreds more before then. Currently about 1,200 species of birds are threatened with extinction by human activities, though efforts are underway to protect them.   Birds can often safely perch on a power line without being electrocuted. For the bird (or other animal) to be electrocuted, a potential difference must exist across two points of the bird's body (its feet in the case of a bird on a power line). When perching on a single power line, there is no potential difference between the bird's feet, so it is safe. If the bird (or other animal) touches two power lines at a time, or one power line and a ground (like a ground wire or the earth itself), the animal would be electrocuted and die. Many large birds (like eagles and vultures) are electrocuted when their wide wings touch a power line and a ground wire at the same time (often while flying in to land on a power line). Amazon birds    More than 1500 bird species are found in the Amazon Basin, while South America as a whole is home to roughly one-third the world's birds. Many birds found in the Amazon are northern or southern migrants, wintering in or passing though the rainforest at certain times of the year. Macaws are famous for gathering by the hundreds, even thousands, along the clay cliffs of the Amazon river where they feed on minerals which help the birds process toxins found in the seeds they eat. The world's rarest bird is Spix's macaw, a beautiful bird with a dark blue head, a blue body, and a greenish belly with a black mask and bright yellow eye. It has always been rare, limited to palm groves and river edges in small area near the center of Brazil, but recent deforestation, importation of Africaniz ed bees-which took their tree hollows, and over collection for the hobbyists caused this species' demise.

Desert biome

              Deserts cover about one fifth of our planet, and are caused by extremely low rainfall over an area.  Theses biomes are nonetheless home to many plants and animals which have through the course of their evolution adapted to this dry environment.

              Hot and Dry Desert is, as you can tell from the name, hot and dry. Most Hot and Dry Deserts don't have very many plants. They do have some low down plants though. The only animals they have that can survive have the ability to burrow under ground. This is because they would not be able to live in the hot sun and heat. They only come out in the night when it is a little cooler.

              A cold desert is a desert that has snow in the winter instead of just dropping a few degrees in temperature like they would in a Hot and Dry Desert. It never gets warm enough for plants to grow. Just maybe a few grasses and mosses. The animals in Cold Deserts also have to burrow but in this case to keep warm, not cool. That is why you might find some of the same animals here as you would in the Hot and Dry Deserts.

              Deserts cover about one fifth of the Earth's land surface. Most Hot and Dry Deserts are near the Tropic of Cancer or the Tropic of Capricorn. Cold Deserts are near the Arctic part of the world.

               Hot and Dry Deserts temperature ranges from 20 to 25° C. The extreme maximum temperature for Hot Desert ranges from 43.5 to 49° C. Cold Deserts temperature in winter ranges from -2 to 4° C and in the summer 21 to 26° C a year.

              The precipitation in Hot and Dry Deserts and the precipitation in Cold Deserts is different. Hot and Dry Deserts usually have very little rainfall and/or concentrated rainfall in short periods between long rainless periods. This averages out to under 15 cm a year. Cold Deserts usually have lots of snow. They also have rain around spring. This averages out to 15 - 26 cm a year.

               Hot and Dry Deserts are warm throughout the fall and spring seasons and very hot during the summer. the winters usually have very little if any rainfall. Cold Deserts have quite a bit of snow during winter. The summer and the beginning of the spring are barely warm enough for a few lichens, grasses and mosses to grow.

              Hot and Dry Deserts vegetation is very rare. Plants are almost all ground-hugging shrubs and short woody trees. All of the leaves are replete (packed with nutrients). Some examples of these kinds of plant are Turpentine Bush, Prickly Pears, and Brittle Bush. For all of these plants to survive they have to have adaptations. Some of the adaptations in this case are the ability to store water for long periods of time and the ability to stand the hot weather.

                Hot and Dry Deserts animals include small nocturnal (only active at night) carnivores. There are also insects, arachnids, reptiles, and birds. Some examples of these animals are Borrowers, Mourning Wheatears, and Horned Vipers. Cold Deserts have animals like Antelope, Ground Squirrels, Jack Rabbits, and Kangaroo Rats.

Coastal and Cold desert

               Coastal deserts are found in areas that are moderately warm to cool, such as the Neotropic and Nearctic realm. The winters are usually cool and short, while the summers are long and warm  The soil is mostly sandy with a high alkaline content, it is also very porous, so rain seeps quite rapidly into the ground.  Most of the flora in the coastal desert features thick foliage, with  good water retention, and their roots are close to the surface of the ground in order to get enough water before it drains into the soil.

               Cold Desert's plants are scattered. In areas with little shade,about 10 percent of the ground is covered with plants. In some areas of sagebrush it reaches 85 percent. The height of scrub varies from 15 cm to 122 cm. All plants are either deciduous and more or less contain spiny leaves.

               Animals of the coastal desert include rough skinned amphibians, birds of prey, scavenger mammals reptiles and insects; most have adapted quite well to the climate, and again, they are largely nocturnal during the warmer months.

               Perhaps the strangest of all desert biomes is the cold desert, as our perception of the desert is usually associated with the heat of the sun.  But even if there is a moderately high amount of snow and rainfall during the wintertime, the soil is too heavy and alkaline.  Alluvial fans pull some of the salt through the porous soil, so plant life can survive, but then again, as with its arid counterparts, the cold desert offers less than ideal conditions for sustaining delicate plants and animals.

             Most of the animals in the cold desert are burrowers, even the carnivores and reptiles which even though cold-blooded, have made their homes in the cold desert.

            Deer and other larger herbivores are only found during the winter, as the supply of grass is more abundant during that period.

Semi Arid Deserts

             The major deserts of this type include the sagebrush of Utah, Montana and Great Basin. They also include the Nearctic realm (North America, Newfoundland, Greenland, Russia, Europe and northern Asia). The summers are moderately long and dry and like hot deserts, the winters normally bring low concentrations of rainfall. Summer temperatures usually average between 21 - 27° Centigrade. Temperature do not normally go above 38° Centigrade and evening temperatures are cool, at around 10° Centigrade. Cool nights help both plants and animals by reducing moisture loss from transpiration, sweating and breathing.

Animals that live in the Desert Biome

          Different animals live in the different types of deserts. Animals that live in the desert have adaptations to cope with the lack of water, the extreme temperatures and the shortage of food. To avoid daytime heat, many desert animals are nocturnal. They burrow beneath the surface or hide in the shade during the day, emerging at night to eat. Many desert animals do not have to drink at all, they get all the water they need from their food. Most desert animals are small.

         Rarer, but important, are physiological adaptations such as aestivation (dormancy during summer), the absence of sweat glands, the concentration of urine, localized deposits of fat in tails or humps and salt glands to secrete salt without loosing fluids.

          Reptiles with their waterproof skin, production of uric acid instead of urine, hard-shelled eggs and ability to gain body heat directly from the sun and to retreat to shade or underground to avoid heat are exceptionally well adapted to dry lands and, not surprisingly, diverse there.

             There are relatively few large mammals in deserts because most are not capable of storing sufficient water and withstanding the heat. Deserts often provide little shelter from the sun for large animals. The dominant animals of warm deserts are non mammalian vertebrates, such as reptiles.

Desert plants

            Desert plants are uniquely adapted to life in a harsh and sometimes extreme environment. They often look unusual, and are sometimes quite beautiful. While desert plants are often greatly enjoyed in nature, they are also experiencing a growing popularity among landscapers. The same traits which allow desert plants to endure in the desert also make them suitable for low water gardening and xeriscaping. In hot, dry climates, desert plants can be used to assemble a striking and very water efficient garden. In cooler regions, desert plants sometimes do well in greenhouse conditions.

             Several traits set desert plants aside from others. The first is that they tend to be designed to store water, and to use water efficiently. Cacti and succulents, for example, both have dense flesh which is designed to store large amounts of water. Many plants also have long roots to reach deep into the water table for water. Other plants deal with hostile conditions by dying off during extreme weather, and reviving during the rainy season to briefly bloom and scatter seeds. During this small window of time, many visitors come to see the profusion of desert wildflowers.

              Many people associate cacti and succulents with the desert, but there are also a range of other plants. Desert wildflowers such as cliffrose, primrose, chuparose, brittlebush, sagebrush, sand verbena, yellow beeplant, and woolly daisies are common. There are also desert versions of familiar flowers like marigolds, lupines, poppies, sunflowers, chicory, mallow, dandelion,a and lily. During their blooming season, these wildflowers light up the desert with color.

           Deserts also host an assortment of trees and shrubs such as creosote bush, crucifixion bush, desert willow, elephant trees, mesquite, ponderosa pines, Joshua trees, and acacias. Many of these trees have minimal foliage, since water loss through leaves is undesirable for them. They may also be bedecked in thorns to discourage hungry animals, and they often have thick, fleshy trunks and branches.

Major biomes