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Ea Biology of Chordates, , Region - 2. Palaearctic region: This region comprises Eurasia abo tropics and Northern come,, of Africa. ., , Region - 3. Oriental region : This includes tropical Asia and asst cobla, , Region -4. Ethiopian region : This includes Africa and Southern reg! :, , II. Realm Neogaea : It includes one zoogeographical regions. ., , ‘ erica and So, , Region - 5. Neotropical region. This includes South ‘America, Central Am uthem, part of Mexico., , hical regions., , des Australia, New, , boring islands., , III. Realm Notogaea: It includes one zoogeograp! Guinea, Tasmania,, , Region -6. Australian region: This region inclu, Newzealand and some neigh!, , What are Zoogeography realms?, In this massive world, apart from humans and the co, , are many species or organisms distributed diversely across the, existing animals (normally vertebrates), usually isolated geograp, but sometimes separated by mountain ranges or other phys!, zoogeographical realms. Just like a country consists of states, simi, , into ZOO-GEOGRAPHICAL REALMS, meaning having a charac, the world into SIX zoo-geographical realms was postulated first by Alfred Russel Wallace, who is, , the father of bio-geography., Formation of such realms emphasizes two factors such as plate tectonics and changing, , pattern of distribution of species. Six divisions of fé i roposed by Sclater in 1875,, Sclater regions were later on con firmed by Wallace in 1876. The regions are:, mmon animals that we know, there, globe. Dissimilar distributions of, hically and defined by continents,, iographic features constitutes, larly the whole world is divided, teristic fauna. This division of, , 1. Palaearctic. 2. Ethiopian 3. Oriental __, 4. Australian Ss Nearcti Neotropical, Each-of these realms or regions is further divided into sub-regions. Each sub-region is, , unique on its own providing optimum environmental condition for the growth and breeding of, , diversified group of organisms. The sub-region under each realms are :, , 1. PALAEARCTIC REGION: Biggest realm, bounded by sea in west, north and east and by, Sahara and Himalayas in the south. This region shows wide range of temperature and rainfall, fluctuations. It includes four sub-regions., ® EUROPEAN: Includes northern and southern Europe, Black sea, Caucasus. This region, , is represented by 85 families of vertebrates. The peculiar mammal to this region, , is Myogale (Desmans). Birds like Tits, wagtails and some of the mammals like wolves, and moles are common in this sub-region., , _ acs Includes south of Alps, Balkans and Caucasus, portion of Arabia,, , , a - h i eset and Baluchistan upto bank of Indus. This sub-region is, , characterised by families of terrestrial vertebrates including birds like Upupa and, Pastor and mammals like Wild ass, Porcupine and Hyaena mu, , e SIBERIAN: Includes Caspian sea to Kamchatka and Bahring’s starits from Arctic se4 to, , Himalayas. It comprises of 94 vertebrate famili, mil; ; 5, are Antelopes, Reindeers, Seal (Phoca sibirica). ies. Mammals confined to this regio

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AN: Includes Korea, J, , nCHURI , rea, Japan, Manchuri 7, , ' wr mountain. Mammals like Tibetan Langur Gr upto Amur rivers and China upto, Nan notes) are unique to this region. ; Great Panda and Chinese water deer, , ION: Region ab ., cTic REG gion above the tropics of North ;, , Fe A : 5, 4M yipel9e? and the Greenland. This region is known as tot fant eck the Arctic, on do! jnance of the tailed amphibians. Nearctic region sh adquarters of urodela” because, , : Hauer show: sainne tH chinatl, ofthe ns and temperatures: This region is also further divided ier a, , LIFORNIA: Includes a part of North America, Nevada, Cascade regions an d part of, , itish Columbia. Contains nearly 86 families of vertebrates. Vampire bats and free tailed, , pats are unique to this region., , EON arian Bond of East California. 107 families of terresterial, vertebra! rican Bison and poiso' i eae, animals of this sub-region. poisonous lizard (Heloderma) are characteristie, , ALLEGHASY: Includes lakes of eastern parts of U.S.A. and rocky mountain sub-region, gs well. This sub-region is unique as it contains Star nosed moles and Opossums among, mammals and Turkeys and Carolina parrots among birds., , CANADIAN: Includes remaining parts of North America and Greenland. Characteristic, vertebrates are Elk, Polar beer and Gluttons and Arctic fox., , ETHIOPIAN REGION: Includes whole of Africa, Southern Arabia and Madagascar. This, , region shows extensive desert on north, thick forests On its western side and grassland in the, , rest of the Africa. It is divided into four sub-regions:, « EAST AFRICAN: Includes Sahara desrt, North-East Africa, Southern Arabia and upto, Zambezi in the south. Comprises of 145 families of vertebrates among which the peculiar, , ones are Crested rats and Whale headed birds. Because of the high temperature Desert, , ostrich, Zebra, Giraffe and Camels are also common., , + WEST AFRICAN: Includes west Africa upto river Congo. This sub-region shows heavy, ind Elephants are common., , rainfall with thick forests. Apes, Panthers, Lions a!, « SOUTH AFRICAN: Includes southern African valley. Peculiar fauna includes African, moles, Bandicoots, Secretary birds and South African Lungfish (Protopterus)., , « MALAGASY: Includes Madagascar and nearby islands. Among mammals Lemurs, among, d among reptiles Pipe snakes are common., , birds Helemt vanga an', ded by Himalayas in north and Indian and Pacific, , . ORIENTAL REGION: This region is boun, oceans in south. No definite boun in South East 1s present. Divided into four sub-regions:, , + INDIAN: Includes India along with Bhutan, Nepal and Maldives. Wide variation of, , temperature and rainfall including mountains, forests, deserts. Peculiar species are Indian, bear, Peacock, Indian bison, Colubrine snake and Rhinoceros., , * CEYLONESE: Includes Ceylon (Sri Lanka). This sub-region shows tropical climate., , Endemic species are Shield tail, Spring rat., , * INDO-CHINESE: Includes China, Myanmar, Thailand, Laos, Cambodia, Vietnam, Taiwan,, , Island of Andaman. Peculiar species includes Panda, Flying Lemur, Malayan Tapir, Disc, tongued frog and salamander., }, , |

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Biology of Chordates, e, Pail ALAYAN: Includes Mal, , Philippines, . bar). S) : :, Broad bills, Petia oe climate and the unique fauna includes Malayan Tapiy,, , 5. NEOTROP, separated fee REGION: Joined to Nearctic region by Central American Isthmus ang, (Amazon vall a the other regions by sea. Known for the-presence of luxurious forests, alley), Plains (Savanna), Mountain (Andes) and complete absence of desert. The, , four sub-regions are:, , ° CHILLIAN ? Includes Western coast of South America, Andes mountain ranges, Peru,, Bolivia and Argentina. The unique species are 3 toed ostrich known as Rhea Americana,, Llamas, Oil birds and Chinchillas., , ¢ BRAZILLIAN: From Isthmus of Panama to La Plata in south. American monkeys,, Armadillos, Spiny mice, Anaconda are common in this sub-region., , ¢ MEXICAN: Includes Mexico and Guatemala. Comprises mainly of rocky mountains and, this sub-region is also said to be the “Transition Zone” between Nearctic and Neotropical, region. Terrapins are mostly found here., , e ANTILLEAN: Includes West Indies islands (Cuba, Haiti, Jamaica, Porto Rico). This subregion shows uniformly high temperature and rainfall. The vertebrate fauna is poor and, , hence no endemic mammals are found., , AUSTRALIAN REGION: This region includes whole Australia, New Zealand, New Guinea,, Molucca and all Pacific islands. Climate is hot and tropical in northern part, hot and arid in, , central part and temperate and cool in southern part. Divided into four sub-regions as following:, e¢ AUSTRALIAN: Includes Australian mainland and Tasmania. This sub-region is known, as “HOME OF MA. ”. Wombats, Marsupial moles, Platypus, Scrub birds and, Emus are endemic to this sub-region., e NEWZEALAND: Includes New Zealand and surrounding islands. Mammals present here, are Bats and Murids. Birds common to this sub-region are Kiwi, Owl parrots, Nestor parrots., One interesting trait here is the absence of snakes., e¢ POLYNESIAN: Includes many Pacific islands like Hawaiian island, Samoa island, Fiji,, Caroline island. Poor endemic fauna, mainly characterized by Tooth billed pigeons., e AUSTRO-MALAYAN: Includes New Guinea and islands of Malay Archipelago. The, endemic species are Crowned pigeon, Flying river turtle, Cassowaries, Tree frogs., ASIC ieRERL Len GR A ie RE, , laya peninsula and Malay Archipelago (Sumatra, Bali,, , 2 se, , —— = = = Se 2, Se SN, , =

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HEORIES PERTAINING T, ODIST, TRIBUTION RIBUTIO, Is OF VERTEBRATES IN DIFFERENT REAL Ms, opUCTION) a, Zoological distribution, is the scj, surface of the globe (both land and Taehs ers, , land-surface of the globe are, inhabited by di, erent faunas. These differences, are not due , ling, with the distribution of living animals on, cee that of their forerunners. Different parts of, rent kinds of animals, or, in other words, by, , js natural to suppose that the fauna of an isl d whe ee ean, and will differ from that of the adj i, \jacent continent., , Alfred Wegener (1904, 1912, > » 19! :, , all continents fitted together like a ji ° 4), from close studies of maps, discovered that coastlines, ced together in a mass of superconti igsaw puzzle, suggesting that all continents in the past were, fal (silica <a befieved that continents, made of light material, , Sean inium) floated over a heavier material Sima (made of silica and Magnesium), tmakes ocean floors, like icebergs floating in ocean water. and Nlagns =, on a a 1960s, detailed studies of ocean floors revealed that the earth’s crust, whi, de of har co S and soil, is broken into several plates that float over the molten mass of the, nerior of earth, Continents move because the crust is broken into blocks or plates that float ‘on the, ot molten lava of mantle that keeps in circulati ; by-theeat emanating from the core. During the Cambrian period major land masses occurred south of, , juator and Africa, SouttrAmerica, Australia, Antarctica and parts of Asia formed a single continental, ass, Gondwanalan t extended up to the South Pole. There was sharp decrease in the, , ospheric CO, during this period perhaps because of invasion of land by plants. Invasion of land, y plants attracted invertebrates and then vertebrates on land, pioneers among them must have, en detrivores rather than plant feeders, such as springtails, millipedes and mites., , ‘ ers, EORIES OF DISTRIBUTION., , Several theories have been put, , eir place of origin to where they are no, , ch is, , forward to explain how and why animals spread from, w found, sometimes travelling thousands of kilometres, , d crossing barriers in the process. Theory of continental drift and existence of corridors and, , Iter bridges between two land masses also explain et of animals. In addition to these the, following theories explain the distribution of plants and animals across continents. _, , _ Brown’s theory of centriu al speciation. It has been observed that largest populations ofa, species exist in the most favourable areas. Due to et numbers a population pressure may, uild up forcing some pioneers t0 venture into the perp ic rie which may not be as habitable., his leads to isolation and speciation that vel Sue ota , aga to periphery due to the, centrifugal force generated by the population press Species., , 2 is. J.C. Willis (1949) BEY this theory based orhis studies on, Bes ane MIe® mS al ency to enlarge their range of distribution slowly in all directions