Middle East
The Middle East is a transcontinental region centered on Western Asia and Egypt. Saudi Arabia is geographically the largest Middle Eastern nation; the corresponding adjective is Middle Eastern and the derived noun is Middle Easterner. The term has come into wider usage as a replacement of the term Near East beginning in the early 20th century. Arabs, Persians and Azeris constitute the largest ethnic groups in the region by population. Arabs constitute the largest ethnic group in the region by a clear margin. Indigenous minorities of the Middle East include Jews, Assyrians, Copts, Lurs, Samaritans, Shabaks and Zazas. European ethnic groups that form a diaspora in the region include Albanians, Circassians, Crimean Tatars, Franco-Levantines, Italo-Levantines. Among other migrant populations are Chinese, Indians, Pakistanis, Pashtuns and sub-Saharan Africans; the history of the Middle East dates back to ancient times, with the importance of the region being recognized for millennia. Several major religions have their origins in the Middle East, including Judaism and Islam.
The Middle East has a hot, arid climate, with several major rivers providing irrigation to support agriculture in limited areas such as the Nile Delta in Egypt, the Tigris and Euphrates watersheds of Mesopotamia, most of what is known as the Fertile Crescent. Most of the countries that border the Persian Gulf have vast reserves of crude oil, with monarchs of the Arabian Peninsula in particular benefiting economically from petroleum exports; the term "Middle East" may have originated in the 1850s in the British India Office. However, it became more known when American naval strategist Alfred Thayer Mahan used the term in 1902 to "designate the area between Arabia and India". During this time the British and Russian Empires were vying for influence in Central Asia, a rivalry which would become known as The Great Game. Mahan realized not only the strategic importance of the region, but of its center, the Persian Gulf, he labeled the area surrounding the Persian Gulf as the Middle East, said that after Egypt's Suez Canal, it was the most important passage for Britain to control in order to keep the Russians from advancing towards British India.
Mahan first used the term in his article "The Persian Gulf and International Relations", published in September 1902 in the National Review, a British journal. The Middle East, if I may adopt a term which I have not seen, will some day need its Malta, as well as its Gibraltar. Naval force has the quality of mobility; the British Navy should have the facility to concentrate in force if occasion arise, about Aden and the Persian Gulf. Mahan's article was reprinted in The Times and followed in October by a 20-article series entitled "The Middle Eastern Question," written by Sir Ignatius Valentine Chirol. During this series, Sir Ignatius expanded the definition of Middle East to include "those regions of Asia which extend to the borders of India or command the approaches to India." After the series ended in 1903, The Times removed quotation marks from subsequent uses of the term. Until World War II, it was customary to refer to areas centered around Turkey and the eastern shore of the Mediterranean as the "Near East", while the "Far East" centered on China, the Middle East meant the area from Mesopotamia to Burma, namely the area between the Near East and the Far East.
In the late 1930s, the British established the Middle East Command, based in Cairo, for its military forces in the region. After that time, the term "Middle East" gained broader usage in Europe and the United States, with the Middle East Institute founded in Washington, D. C. in 1946, among other usage. The description Middle has led to some confusion over changing definitions. Before the First World War, "Near East" was used in English to refer to the Balkans and the Ottoman Empire, while "Middle East" referred to Iran, the Caucasus, Central Asia, Turkestan. In contrast, "Far East" referred to the countries of East Asia With the disappearance of the Ottoman Empire in 1918, "Near East" fell out of common use in English, while "Middle East" came to be applied to the re-emerging countries of the Islamic world. However, the usage "Near East" was retained by a variety of academic disciplines, including archaeology and ancient history, where it describes an area identical to the term Middle East, not used by these disciplines.
The first official use of the term "Middle East" by the United States government was in the 1957 Eisenhower Doctrine, which pertained to the Suez Crisis. Secretary of State John Foster Dulles defined the Middle East as "the area lying between and including Libya on the west and Pakistan on the east and Iraq on the North and the Arabian peninsula to the south, plus the Sudan and Ethiopia." In 1958, the State Department explained that the terms "Near East" and "Middle East" were interchangeable, defined the region as including only Egypt, Israel, Jordan, Saudi Arabia, Kuwait and Qatar. The Associated Press Styleboo
Iran
Iran called Persia, the Islamic Republic of Iran, is a country in Western Asia. With over 81 million inhabitants, Iran is the world's 18th most populous country. Comprising a land area of 1,648,195 km2, it is the second largest country in the Middle East and the 17th largest in the world. Iran is bordered to the northwest by Armenia and the Republic of Azerbaijan, to the north by the Caspian Sea, to the northeast by Turkmenistan, to the east by Afghanistan and Pakistan, to the south by the Persian Gulf and the Gulf of Oman, to the west by Turkey and Iraq; the country's central location in Eurasia and Western Asia, its proximity to the Strait of Hormuz, give it geostrategic importance. Tehran is the country's capital and largest city, as well as its leading economic and cultural center. Iran is home to one of the world's oldest civilizations, beginning with the formation of the Elamite kingdoms in the fourth millennium BCE, it was first unified by the Iranian Medes in the seventh century BCE, reaching its greatest territorial size in the sixth century BCE, when Cyrus the Great founded the Achaemenid Empire, which stretched from Eastern Europe to the Indus Valley, becoming one of the largest empires in history.
The Iranian realm fell to Alexander the Great in the fourth century BCE and was divided into several Hellenistic states. An Iranian rebellion culminated in the establishment of the Parthian Empire, succeeded in the third century CE by the Sasanian Empire, a leading world power for the next four centuries. Arab Muslims conquered the empire in the seventh century CE; the Islamization of Iran led to the decline of Zoroastrianism, by the country's dominant religion, Iran's major contributions to art and science spread within the Muslim rule during the Islamic Golden Age. After two centuries, a period of various native Muslim dynasties began, which were conquered by the Seljuq Turks and the Ilkhanate Mongols; the rise of the Safavids in the 15th century led to the reestablishment of a unified Iranian state and national identity, with the country's conversion to Shia Islam marking a turning point in Iranian and Muslim history. Under Nader Shah, Iran was one of the most powerful states in the 18th century, though by the 19th century, a series of conflicts with the Russian Empire led to significant territorial losses.
The Iranian Constitutional Revolution in the early 20th century led to the establishment of a constitutional monarchy and the country's first legislature. A 1953 coup instigated by the United Kingdom and the United States resulted in greater autocracy and growing Western political influence. Subsequent widespread dissatisfaction and unrest against the monarchy led to the 1979 Revolution and the establishment of an Islamic republic, a political system that includes elements of a parliamentary democracy vetted and supervised by a theocracy governed by an autocratic "Supreme Leader". During the 1980s, the country was engaged in a war with Iraq, which lasted for eight years and resulted in a high number of casualties and economic losses for both sides; the sovereign state of Iran is a founding member of the UN, ECO, NAM, OIC, OPEC. It is a major regional and middle power, its large reserves of fossil fuels – which include the world's largest natural gas supply and the fourth largest proven oil reserves – exert considerable influence in international energy security and the world economy.
The country's rich cultural legacy is reflected in part by its 22 UNESCO World Heritage sites, the third largest number in Asia and 11th largest in the world. Iran is a multicultural country comprising numerous ethnic and linguistic groups, the largest being Persians, Azeris and Lurs. Organizations including Amnesty International and Human Rights Watch have criticized Iran's women's rights record; the term Iran derives directly from Middle Persian Ērān, first attested in a third-century inscription at Rustam Relief, with the accompanying Parthian inscription using the term Aryān, in reference to the Iranians. The Middle Iranian ērān and aryān are oblique plural forms of gentilic nouns ēr- and ary-, both deriving from Proto-Iranian *arya-, recognized as a derivative of Proto-Indo-European *ar-yo-, meaning "one who assembles". In the Iranian languages, the gentilic is attested as a self-identifier, included in ancient inscriptions and the literature of the Avesta, remains in other Iranian ethnic names Alan and Iron.
Iran has been referred to as Persia by the West, due to the writings of Greek historians who referred to all of Iran as Persís, meaning "land of the Persians", while Persis itself was one of the provinces of ancient Iran, today defined as Fars. As the most extensive interaction the Ancient Greeks had with any outsider was with the Persians, the term persisted long after the Greco-Persian Wars. In 1935, Reza Shah requested the international community to refer to the country by its native name, effective March 22 that year; as The New York Times explained at the time, "At the suggestion of the Persian Legation in Berlin, the Tehran government, on the Persian New Year, March 21, 1935, substituted Iran for Persia as the official name of the country." Opposition to the name change led to the reversal of the decision, Professor Ehsan Yarshater, editor of Encyclopædia Iranica, propagated a move to use Persia and Iran interchangeably. Today, both Iran and Persia are used in cultural contexts, while Iran remains irreplaceab
Mammal
Mammals are vertebrate animals constituting the class Mammalia, characterized by the presence of mammary glands which in females produce milk for feeding their young, a neocortex, fur or hair, three middle ear bones. These characteristics distinguish them from reptiles and birds, from which they diverged in the late Triassic, 201–227 million years ago. There are around 5,450 species of mammals; the largest orders are the rodents and Soricomorpha. The next three are the Primates, the Cetartiodactyla, the Carnivora. In cladistics, which reflect evolution, mammals are classified as endothermic amniotes, they are the only living Synapsida. The early synapsid mammalian ancestors were sphenacodont pelycosaurs, a group that produced the non-mammalian Dimetrodon. At the end of the Carboniferous period around 300 million years ago, this group diverged from the sauropsid line that led to today's reptiles and birds; the line following the stem group Sphenacodontia split off several diverse groups of non-mammalian synapsids—sometimes referred to as mammal-like reptiles—before giving rise to the proto-mammals in the early Mesozoic era.
The modern mammalian orders arose in the Paleogene and Neogene periods of the Cenozoic era, after the extinction of non-avian dinosaurs, have been among the dominant terrestrial animal groups from 66 million years ago to the present. The basic body type is quadruped, most mammals use their four extremities for terrestrial locomotion. Mammals range in size from the 30–40 mm bumblebee bat to the 30-meter blue whale—the largest animal on the planet. Maximum lifespan varies from two years for the shrew to 211 years for the bowhead whale. All modern mammals give birth to live young, except the five species of monotremes, which are egg-laying mammals; the most species-rich group of mammals, the cohort called placentals, have a placenta, which enables the feeding of the fetus during gestation. Most mammals are intelligent, with some possessing large brains, self-awareness, tool use. Mammals can communicate and vocalize in several different ways, including the production of ultrasound, scent-marking, alarm signals and echolocation.
Mammals can organize themselves into fission-fusion societies and hierarchies—but can be solitary and territorial. Most mammals are polygynous. Domestication of many types of mammals by humans played a major role in the Neolithic revolution, resulted in farming replacing hunting and gathering as the primary source of food for humans; this led to a major restructuring of human societies from nomadic to sedentary, with more co-operation among larger and larger groups, the development of the first civilizations. Domesticated mammals provided, continue to provide, power for transport and agriculture, as well as food and leather. Mammals are hunted and raced for sport, are used as model organisms in science. Mammals have been depicted in art since Palaeolithic times, appear in literature, film and religion. Decline in numbers and extinction of many mammals is driven by human poaching and habitat destruction deforestation. Mammal classification has been through several iterations since Carl Linnaeus defined the class.
No classification system is universally accepted. George Gaylord Simpson's "Principles of Classification and a Classification of Mammals" provides systematics of mammal origins and relationships that were universally taught until the end of the 20th century. Since Simpson's classification, the paleontological record has been recalibrated, the intervening years have seen much debate and progress concerning the theoretical underpinnings of systematization itself through the new concept of cladistics. Though field work made Simpson's classification outdated, it remains the closest thing to an official classification of mammals. Most mammals, including the six most species-rich orders, belong to the placental group; the three largest orders in numbers of species are Rodentia: mice, porcupines, beavers and other gnawing mammals. The next three biggest orders, depending on the biological classification scheme used, are the Primates including the apes and lemurs. According to Mammal Species of the World, 5,416 species were identified in 2006.
These were grouped into 153 families and 29 orders. In 2008, the International Union for Conservation of Nature completed a five-year Global Mammal Assessment for its IUCN Red List, which counted 5,488 species. According to a research published in the Journal of Mammalogy in 2018, the number of recognized mammal species is 6,495 species included 96 extinct; the word "mammal" is modern, from the scientific name Mammalia coined by Carl Linnaeus in 1758, derived from the Latin mamma. In an influential 1988 paper, Timothy Rowe defined Mammalia phylogenetically as the crown group of mammals, the clade consisting of the most recent common ancestor of living monotremes and therian m
Mount Damavand
Mount Damavand, a active volcano, is a stratovolcano, the highest peak in Iran and the highest volcano in Asia. Damāvand has a special place in Persian folklore, it is in the middle of the Alborz range, adjacent to Varārū, Gol-e Zard, Mīānrūd. It is near the southern coast of the Caspian Sea, in Amol County, Mazandaran Province, 66 kilometres northeast of the city of Tehran. Mount Damāvand is the 12th most prominent peak in the world, the second most prominent in Asia after Mount Everest, it is the highest volcanic mountain in Asia, part of the Volcanic Seven Summits mountaineering challenge. Damavand is a significant mountain in Persian mythology, it is the symbol of Iranian resistance against despotism and foreign rule in Persian poetry and literature. In Zoroastrian texts and mythology, the three-headed dragon Aži Dahāka was chained within Mount Damāvand, there to remain until the end of the world. In a version of the same legend, the tyrant Zahhāk was chained in a cave somewhere in Mount Damāvand after being defeated by Kāveh and Fereydūn.
Persian poet Ferdowsi depicts this event in his masterpiece, the Shahnameh: بیاورد ضحاک را چون نوند به کوه دماوند کردش ببند biyâvarad Zahhâk râ čon navand be kuh-e Damâvand krdš beband He brought Zahhak like a horse to mount Damavand, And tied him at the peak tight and bound The mountain is said to hold magical powers in the Shahnameh. Damāvand has been named in the Iranian legend of Arash as the location from which the hero shot his magical arrow to mark the border of Iran, during the border dispute between Iran and Turan; the poem Damāvand by Mohammad Taqī Bahār is one fine example of the mountain's significance in Persian literature. The first verse of this poem reads: ای دیو سپید پای در بند ای گنبد گیتی، ای دماوند Ey div-e sepid-e pâyi dar band, Ey gonbad-e giti, ey Damāvand O white giant with feet in chains O dome of the world, O Damāvand Mount Damavand is depicted on the reverse of the Iranian 10,000 rials banknote; the origins and meaning of the word "Damavand" is unclear, yet some prominent researchers have speculated that it means "The mountain from which smoke and ash arises", alluding to the volcanic nature of the mountain.
Mount Damavand first erupted in the Pleistocene 1.78 million years ago. After several known eruptions around 600,000 and 280,000 years ago, its last eruption was around 5300 BC in the Holocene, its steep cone is formed of ash and lava flows of trachyte and basalt. The Quaternary lavas are directly on the Jurassic sediments; the volcano is crowned by a small crater with sulfuric deposits. There are fumaroles, hot springs, mineral deposits of travertine. Mount Damavand could be considered as a active volcano, because there are fumaroles near the summit crater emitting sulfur, which were known to be active on July 6, 2007. Mineral hot springs are located on the volcano's flanks and at the base, giving evidence of volcanic heat comparatively near the surface of the earth. While no historic eruptions have been recorded, hot springs at the base and on the flanks, fumaroles and solfatara near the summit, indicate a hot or cooling magma body still present beneath the volcano; the most important of these hot springs are located in Abe Garm Larijan in a village by the name Larijan in the district of Larijan in Lar Valley.
The water from this spring is useful in the treatment of chronic wounds and skin diseases. Near these springs there are public baths with small pools for public use. A major settlement for mountain climbers is the new Iranian Mountain Federation Camp in the village of Polour, located on the south of the mountain. There are at least 16 known routes with varying levels of difficulty; some of them require rock climbing. The most popular route is the southern route which has steps and a camp midway called Bargah Sevom Camp/Shelter at 4,220 m; the longest route is the Northeastern and it takes two days to reach the summit starting from downhill village of Nāndal and a night stay at Takht-e Fereydoun (elevation 4,300 m, a two-story shelter. The western route is noted for its sunset view. Sīmorgh shelter in this route at 4,100 m is a newly constructed two story shelter. There is a frozen waterfall/icefall about 12 m tall and the elevation of 5,100 m is the highest fall in Iran and Middle East. Damavand rivers and slopes are famous for brown trout.
Armenian mouflon and wild goat live in the region of Damavand Mts. Persian leopard and Syrian brown bear live in this region; some smaller mammals are mouse-like hamster and Afghan pika. The attractive and unreachable Caspian snowcock lives at high altitudes. Golden eagle breeds in this area. Griffon vultures are common. Chukar partridge has nests between stone and shrubs. Red-fronted serin, snow finch, rock sparrow, rock bunting and horned lark are native. In spring wheatear, rock thrush, nightingale come from Africa for breeding. Grey-necked bunting, black-headed bunting and commo
Roe deer
The European roe deer known as the western roe deer, chevreuil, or roe deer or roe, is a species of deer. The male of the species is sometimes referred to as a roebuck; the roe deer is small and grey-brown, well-adapted to cold environments. The species is widespread in Europe, from the Mediterranean to Scandinavia, from Scotland to the Caucasus, east to northern Iran and Iraq, it is distinct from the somewhat larger Siberian roe deer. Within Europe, the European roe deer occurs in most areas, with the exception of northernmost Scandinavia and some of the islands, notably Iceland and the Mediterranean Sea islands. Scottish roe deer were introduced to the Lissadell Estate in Co. Sligo in Ireland around 1870 by Sir Henry Gore-Booth, Bt; the Lissadell deer were noted for their occasional abnormal antlers and survived in that general area for about 50 years before they died out. According to the National Biodiversity Data Centre, in 2014 there was a confirmed sighting of roe deer in County Armagh. There have been other, sightings in County Wicklow.
In England and Wales, roe have experienced a substantial expansion in their range in the latter half of the 20th century and continuing into the 21st century. This increase in population appears to be affecting woodland ecosystems. At the start of the 20th century, they were extinct in Southern England, but since have hugely expanded their range for no apparent reason and in some cases with human help. In 1884, roe were introduced from Württemberg in Germany into the Thetford Chase area, these spread to populate most of Norfolk and substantial parts of Cambridgeshire. In southern England, they started their expansion in Sussex and from there soon spread into Surrey, Wiltshire and Dorset, for the first half of the 20th century, most roe in southern England were to be found in these counties. By the end of the 20th century, they had repopulated much of Southern England and had expanded into Somerset, Cornwall, Gloucestershire, Warwickshire and South Yorkshire, had spread into mid-Wales from the Ludlow area where an isolated population had appeared.
At the same time, the surviving population in Scotland and the Lake District had pushed further south beyond Yorkshire and Lancashire and into Derbyshire and Humberside. Roe can now be found in most of rural England except for south east Kent and the greater part of Staffordshire and Cheshire, although the expansion is continuing to the extent that before the end of the 21st century, anywhere in the UK mainland suitable for roe may have a population. Not being a species that needs large areas of woodland to survive, urban roe are now a feature of several cities, notably Glasgow and Bristol, where in particular they favour cemeteries. In Wales, they are less common, but have been seen as far south west as Cardigan and as far north west as Bangor, they are reasonably well established in Powys and Monmouthshire. German colonial administrators introduced roe deer to the island of Pohnpei in Micronesia, they are hunted by locals in steep and vegetated terrain. The meat is sold in markets and restaurants in Kolonia, the capital city of Pohnpei and the Federated States of Micronesia.
The roe deer is distinct from the somewhat larger Siberian roe deer found from the Ural Mountains to as far east as China and Siberia. The two species meet at the Caucasus Mountains, with the European species occupying the southern flank of the mountain ranges and adjacent Asia Minor, the Siberian species occupying the northern flank of the mountain ranges, it is known. The roe deer is a small deer, with a body length of 95–135 cm, a shoulder height of 65–75 cm, a weight of 15–35 kg. Bucks in good conditions develop antlers up to 20–25 cm long with two or three even four, points; when the male's antlers begin to regrow, they are covered in a thin layer of velvet-like fur which disappears on after the hair's blood supply is lost. Males may speed up the process by rubbing their antlers on trees, so that their antlers are hard and stiff for the duels during the mating season. Unlike most cervids, roe deer begin regrowing antlers immediately after they are shed; the roe deer is crepuscular quick and graceful, lives in woods, although it may venture into grasslands and sparse forests.
They feed on grass, leaves and young shoots. They like young, tender grass with a high moisture content, i.e. grass that has received rain the day before. Roe deer will not venture into a field that has had or has livestock in it because the livestock make the grass unclean. A pioneer species associated with biotic communities at an early stage of succession, during the Neolithic period in Europe, the roe deer was abundant, taking advantage of areas of forest or woodland cleared by Neolithic farmers; the roe deer attains a maximum lifespan of 10 years. When alarmed, it will flash out its white rump patch. Rump patches differ between the sexes, with the white rump patches heart-shaped on females and kidney-shaped on males. Males may bark or make a low grunting noise. Females make a high-pitched "pheep" whine to attract males during the rut in August; the female goes looking for a mate and lures the
Animal
Animals are multicellular eukaryotic organisms that form the biological kingdom Animalia. With few exceptions, animals consume organic material, breathe oxygen, are able to move, can reproduce sexually, grow from a hollow sphere of cells, the blastula, during embryonic development. Over 1.5 million living animal species have been described—of which around 1 million are insects—but it has been estimated there are over 7 million animal species in total. Animals range in length from 8.5 millionths of a metre to 33.6 metres and have complex interactions with each other and their environments, forming intricate food webs. The category includes humans, but in colloquial use the term animal refers only to non-human animals; the study of non-human animals is known as zoology. Most living animal species are in the Bilateria, a clade whose members have a bilaterally symmetric body plan; the Bilateria include the protostomes—in which many groups of invertebrates are found, such as nematodes and molluscs—and the deuterostomes, containing the echinoderms and chordates.
Life forms interpreted. Many modern animal phyla became established in the fossil record as marine species during the Cambrian explosion which began around 542 million years ago. 6,331 groups of genes common to all living animals have been identified. Aristotle divided animals into those with those without. Carl Linnaeus created the first hierarchical biological classification for animals in 1758 with his Systema Naturae, which Jean-Baptiste Lamarck expanded into 14 phyla by 1809. In 1874, Ernst Haeckel divided the animal kingdom into the multicellular Metazoa and the Protozoa, single-celled organisms no longer considered animals. In modern times, the biological classification of animals relies on advanced techniques, such as molecular phylogenetics, which are effective at demonstrating the evolutionary relationships between animal taxa. Humans make use of many other animal species for food, including meat and eggs. Dogs have been used in hunting, while many aquatic animals are hunted for sport.
Non-human animals have appeared in art from the earliest times and are featured in mythology and religion. The word "animal" comes from the Latin animalis, having soul or living being; the biological definition includes all members of the kingdom Animalia. In colloquial usage, as a consequence of anthropocentrism, the term animal is sometimes used nonscientifically to refer only to non-human animals. Animals have several characteristics. Animals are eukaryotic and multicellular, unlike bacteria, which are prokaryotic, unlike protists, which are eukaryotic but unicellular. Unlike plants and algae, which produce their own nutrients animals are heterotrophic, feeding on organic material and digesting it internally. With few exceptions, animals breathe oxygen and respire aerobically. All animals are motile during at least part of their life cycle, but some animals, such as sponges, corals and barnacles become sessile; the blastula is a stage in embryonic development, unique to most animals, allowing cells to be differentiated into specialised tissues and organs.
All animals are composed of cells, surrounded by a characteristic extracellular matrix composed of collagen and elastic glycoproteins. During development, the animal extracellular matrix forms a flexible framework upon which cells can move about and be reorganised, making the formation of complex structures possible; this may be calcified, forming structures such as shells and spicules. In contrast, the cells of other multicellular organisms are held in place by cell walls, so develop by progressive growth. Animal cells uniquely possess the cell junctions called tight junctions, gap junctions, desmosomes. With few exceptions—in particular, the sponges and placozoans—animal bodies are differentiated into tissues; these include muscles, which enable locomotion, nerve tissues, which transmit signals and coordinate the body. There is an internal digestive chamber with either one opening or two openings. Nearly all animals make use of some form of sexual reproduction, they produce haploid gametes by meiosis.
These fuse to form zygotes, which develop via mitosis into a hollow sphere, called a blastula. In sponges, blastula larvae swim to a new location, attach to the seabed, develop into a new sponge. In most other groups, the blastula undergoes more complicated rearrangement, it first invaginates to form a gastrula with a digestive chamber and two separate germ layers, an external ectoderm and an internal endoderm. In most cases, a third germ layer, the mesoderm develops between them; these germ layers differentiate to form tissues and organs. Repeated instances of mating with a close relative during sexual reproduction leads to inbreeding depression within a population due to the increased prevalence of harmful recessive traits. Animals have evolved numerous mechanisms for avoiding close inbreeding. In some species, such as the splendid fairywren, females benefit by mating with multiple males, thus producing more offspring of higher genetic quality; some animals are capable of asexual reproduction, which results
Carnivora
Carnivora is a diverse scrotiferan order that includes over 280 species of placental mammals. Its members are formally referred to as carnivorans, whereas the word "carnivore" can refer to any meat-eating organism. Carnivorans are the most diverse in size of any mammalian order, ranging from the least weasel, at as little as 25 g and 11 cm, to the polar bear, which can weigh up to 1,000 kg, to the southern elephant seal, whose adult males weigh up to 5,000 kg and measure up to 6.7 m in length. Carnivorans have teeth and claws adapted for catching and eating other animals. Many hunt in are social animals, giving them an advantage over larger prey; some carnivorans, such as cats and pinnipeds, depend on meat for their nutrition. Others, such as raccoons and bears, are more omnivorous, depending on the habitat; the giant panda is a herbivore, but feeds on fish and insects. The polar bear subsists on seals. Carnivorans are split into two suborders: Caniformia. Carnivorans all share the same arrangement of teeth in which the last upper premolar and the first lower molar have blade-like enamel crowns that work together as carnassial teeth to shear meat.
Carnivorans have had this arrangement for over 60 million years with many adaptions, these dental adaptions help identify carnivoran species and groupings of species. Carnivorans evolved in North America out of members of the family Miacidae about 42 million years ago, they soon split into dog-like forms. Their molecular phylogeny shows the extant Carnivora are a monophyletic group, the crown group of the Carnivoramorpha. Most carnivorans are terrestrial; the last premolar of the upper jaw and first molar of the lower are termed the carnassials or sectorial teeth. These blade-like teeth occlude with a scissor-like action for shredding meat. Carnassials are most developed in the Felidae and the least developed in the Ursidae. Carnivorans have two conical canines in each jaw; the only two exceptions to this are the sea otter, which has four incisors in the lower jaw, the sloth bear, which has four incisors in the upper jaw. The number of molars and premolars is variable between carnivoran species, but all teeth are rooted and are diphyodont.
Incisors are retained by carnivorans and the third incisor is large and sharp. Carnivorans have either four or five digits on each foot, with the first digit on the forepaws known as the dew claw, being vestigial in most species and absent in some; the superfamily Canoidea – Canidae, Mustelidae, Ursidae, Otariidae and Phocidae and the extinct family Amphicyonidae – are characterized by having nonchambered or chambered auditory bullae, nonretractable claws, a well-developed baculum. Most species are rather plain in coloration, lacking the flashy spotted or rosetted coats like many species of felids and viverrids have; this is because Canoidea tend to range in the temperate and subarctic biomes, although Mustelidae and Procyonidae have a few tropical species. Most are terrestrial. All families except the Canidae and a few species of Mustelidae are plantigrade. Diet is varied and most tend to be omnivorous to some degree, thus the carnassial teeth are less specialized. Canoidea have more molars in an elongated skull.
The superfamily Feloidea – Felidae, Herpestidae, Hyaenidae and Eupleridae, as well as the extinct family Nimravidae – have spotted, rosetted or striped coats, tend to be more brilliantly colored than their Canoidean counterparts. This is because these species tend to range in tropical habitats, although a few species do inhabit temperate and subarctic habitats. Many are arboreal or semiarboreal, the majority are digitigrade. Diet tends to be more carnivorous in the family Felidae, they have fewer teeth and shorter skulls, with much more specialized carnassials meant for shearing meat. Feliformia claws are retractile, or semiretractile; the terminal phalanx, with the claw attached, folds back in the forefoot into a sheath by the outer side of the middle phalanx of the digit, is retained in this position when at rest by a strong elastic ligament. In the hindfoot, the terminal joint or phalanx is retracted on to the top, not the side of the middle phalanx. Deep flexor muscles straighten the terminal phalanges, so the claws protrude from their sheaths, the soft "velvety" paw becomes converted into a formidable weapon.
The habitual retraction of the claws preserves their points from wear. The superfamily Pinnipedia, now considered to be part of Caniformia, are medium to large aquatic mammals. Being homeothermic marine mammals, pinni
