whereas the earliest traces of life in fossil record of africa date to the earliest times

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Whereas the earliest traces of life in fossil record of Africa date to the earliest times, [2]  the formation of African fauna as we know it today, began with the splitting up of the  Gondwana supercontinent in the mid-Mesozoic era. The continents Laurasia-Gondwana 200 million years ago  After that , four t o six faunal assemb lages, the so-called A frican Faun al Strata (AFSs) ca n be distinguished. The isolation of Africa was broken intermittently by discontinuous "filter routes" that linked it to some other Gondwanan continents (Madagascar , South America, and perhaps India), but mainly to Laurasia. Interchanges with Gondwana were rare and mainly "out-of-Africa" dispersals, whereas interchanges with Laurasia were numerous and bidirectional, although mainly from Laurasia to Africa. Despite these connections, isolation resulted in remarkable absences, poor diversity, and emergence of endemic taxa in Africa . [3]  Madagascar separated from continental Africa during the break-up of Gondwanaland early in the Cretaceous, but was probably connected to the mainland again in the Eocene. [4]  The first Neogene faunal interchange took place in the Middle Miocene (the introduction of  Myocricetodontinae ,Democricetodontinae , and Dendromurinae). [5]   A major terrestrial fa unal exchange between North Africa and Europe began at about 6.1 Ma, some 0.4 Myr before the beginning of the Messinian salinity crisis [6] (for example introduction of Murinae, immigrants from southern  Asia) [7]  During the early Tertiary, Africa was covered by a vast evergreen forest inhabited by an endemic forest fauna with many types common to southern Asia. In the  Pliocene the climate became dry and most of the forest was destroyed, the forest animals taking refuge in the remaining forest islands. At the same time a broad land-bridge connected Africa with Asia and there was a great invasion of animals of the steppe fauna into Africa. At the beginning of the  Pleistocene a moist period set in and much of the forest was renewed while the grassland fauna was divided and isolated, as the forest fauna had previously been. The present forest fauna is therefore of double origin, partly descended

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Earliest Traces of Life in Fossil Record of Africa Date to the Earliest Times

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Whereas the earliest traces of life in fossil record of Africa date to the earliest times,[2]the formation of African fauna as we know it today, began with the splitting up of theGondwanasupercontinent in the mid-Mesozoic era.

The continents Laurasia-Gondwana 200 million years agoAfter that, four to six faunal assemblages, the so-called African Faunal Strata (AFSs) can be distinguished. The isolation of Africa was broken intermittently by discontinuous "filter routes" that linked it to some other Gondwanan continents (Madagascar,South America, and perhapsIndia), but mainly toLaurasia. Interchanges with Gondwana were rare and mainly "out-of-Africa" dispersals, whereas interchanges with Laurasia were numerous and bidirectional, although mainly from Laurasia to Africa. Despite these connections, isolation resulted in remarkable absences, poor diversity, and emergence of endemic taxa in Africa.[3]Madagascar separated from continental Africa during the break-up of Gondwanaland early in theCretaceous, but was probably connected to the mainland again in theEocene.[4]The first Neogene faunal interchange took place in the Middle Miocene (the introduction ofMyocricetodontinae,Democricetodontinae, andDendromurinae).[5]A major terrestrial faunal exchange between North Africa and Europe began at about 6.1 Ma, some 0.4 Myr before the beginning of theMessinian salinity crisis[6](for example introduction ofMurinae, immigrants from southernAsia)[7]During the earlyTertiary, Africa was covered by a vast evergreen forest inhabited by an endemic forest fauna with many types common to southern Asia. In thePliocenethe climate became dry and most of the forest was destroyed, the forest animals taking refuge in the remaining forest islands. At the same time a broad land-bridge connected Africa with Asia and there was a great invasion of animals of thesteppefauna into Africa. At the beginning of thePleistocenea moist period set in and much of the forest was renewed while the grassland fauna was divided and isolated, as the forest fauna had previously been. The present forest fauna is therefore of double origin, partly descended of the endemic fauna and partly from steppe forms that adapted themselves to forest life, while the present savanna fauna is similarly explained. The isolation in past times has resulted in the presence of closely related subspecies in widely separated regions[8][9]Africa, where humans originated, shows much less evidence of loss in thePleistocene megafaunalextinction, perhaps becauseco-evolutionof large animals alongside early humans provided enough time for them to develop effective defenses.[10]Its situation in the tropics spared it also from Pleistoceneglaciationsand the climate has not changed much[11]The invertebrates[edit]

Giant East African SnailThere are large gaps in human knowledge about African invertebrates. East Africa has a rich coral fauna[12]with about 400 known species. More than 400 species ofEchinodermsand 500 species ofBryozoalive there too,[13]as well as oneCubozoanspecies (Carybdea alata). OfNematodes, theOnchocerca volvulus,Necator americanus,Wuchereria bancroftiandDracunculus medinensisare human parasites. Some of important plant-parasitic nematodes of crops includeMeloidogyne,Pratylenchus,Hirschmanniella,Radopholus,ScutellonemaandHelicotylenchus.[14][15][16][17]Of the fewOnychophoransPeripatus,PeripatopsisandOpisthopatuslive in Africa.[18]Greatest diversity of freshwater mollusks is found in East African lakes. Of marine snails, less diversity is present in Atlantic coast, more in tropical Western Indian Ocean region (over 3000 species of gastropods with 81 endemic species).[19][20]Cowryshells have been used as a money by native Africans. Theland snailfauna is especially rich inAfromontaneregions, and there are some endemic families in Africa (e.g.Achatinidae,Chlamydephoridae) but other tropical families are common too (Charopidae,Streptaxidae,Cyclophoridae,Subulinidae,Rhytididae). 156 tardigrade species have been found,[21][22]and about 8000 species ofarachnids. The African millipedeArchispirostreptus gigasis one of the largest in the world. 20 genera offreshwater crabsare present.[23]The soil animal communities tropical Africa are poorly known. A few ecological studies have been undertaken on macrofauna, mainly in West Africa.[24]Earthworms are being extensively studied in West and South Africa.[25][26]Insects[edit]

Atermitemound inBotswanaApproximately 100,000 species of insects have been described from sub-Saharan Africa, but there are very few overviews of the fauna as a whole[27](it has been estimated that the African insects make up about 10-20% of the global insect species richness,[28]and about 15% of new species descriptions come from Afrotropics[29]). The only endemic African insect order isMantophasmatodea.About 875 African species ofdragonflieshave been recorded.[30]Themigratory locustanddesert locusthave been serious threats to African economies and human welfare.Africa has the biggest number oftermitegenera of all continents,[31]and over 1,000 termite species.OfDiptera, the number of described African species is about 17,000.[32]Natalimyzidae, a new family of acalyptrate flies has been recently described fromSouth Africa.[33]Anopheles gambiae,Aedes aegyptiandTsetse flyare important vectors of diseases.

Acitrus swallowtailfromTanzania1600 species ofbees[34]and 2000 species ofants[35]among otherHymenopteransare known from Africa.There live also 3,607 species ofbutterflies, being the best known group of insects.[36]The caterpillars ofmopanimoth are part of the South African cuisine. Among the numerous species of Africanbeetlesare the famoussacred scarab, theCentaurus beetle, theManticora Tiger Beetleand enormousGoliath beetles.Butterflies[edit]Hotspotsfor butterflies include theCongolian forestsand theGuinean forest-savanna mosaic. Some butterflies (Hamanumida daedalus,Precis,Eurema) are grassland or savannah specialists. Many of these have very large populations and a vast range.South Africahas one of the highest proportions of Lycaenid butterflies (48%) for any region in the world with many species restricted in range. North Africa is in thePalaearctic regionand has a different species assemblage.Generawhich arespecies richin Africa includeCharaxes,Acraea,ColotisandPapilio, most notablyPapilio antimachusandPapilio zalmoxis. The subfamilyLipteninaeisendemicto theAfrotropicsand includes species rich genera such asOrnipholidotos,Liptenara,Pentila,Baliochila,Hypophytala,Teriomima,DeloneuraandMimacraea. TheMiletinaeare mostly African, notablyLachnocnema. Endemic Nymphalidae includeEuphaedra,Bebearia,Precis,Pseudacraea,BicyclusandEuxanthe. Endemic Pieridae includePseudopontia paradoxaandMylothris. Endemic skippers includeSarangesaandKedestes. The highestspecies diversityis in theDemocratic Republic of the Congohome to 2,040 species 181 of which are endemic.Fish[edit]

Latimeria, a living member of along-thought-extinctgroup of fishAfrica is the richest continent offreshwaterfish, with about 3000 species.[37][38]The East African Great Lakes (Victoria,Malawi, andTanganyika) are the center of biodiversity of many fish, especiallycichlids(they harbor more than two-thirds of the estimated 2000 species in the family).[39]The West African coastal rivers region covers only a fraction of West Africa, but harbours 322 of West Africans fish species, with 247 restricted to this area and 129 restricted even to smaller ranges. The central rivers fauna comprises 194 fish species, with 119 endemics and only 33 restricted to small areas.[40]The marine diversity is greatest near the Indian Ocean shore with about 2000 species.[41]Characteristic to African fauna arePerciformes(Lates,tilapias,Dichistiidae,Anabantidae,Mudskippers,Parachanna,Acentrogobius,Croilia,Glossogobius,Hemichromis,Nanochromis,Oligolepis,Oreochromis,Redigobius,Sarotherodon,Stenogobiusand others),Gonorhynchiformes(Kneriidae,Phractolaemidae), somelungfishes(Protopterus), manyCharaciformes(Distichodontidae,Hepsetidae,Citharinidae,Alestiidae),Osteoglossiformes(African knifefish,Gymnarchidae,Mormyridae,Pantodontidae),Siluriformes(Amphiliidae,Anchariidae,Ariidae,Austroglanididae,Clariidae,Claroteidae,Malapteruridae,Mochokidae,Schilbeidae),Osmeriformes(Galaxiidae),Cyprinodontiformes(Aplocheilidae,Poeciliidae) andCypriniformes(Labeobarbus,Pseudobarbus,Tanakiaand others).Amphibians[edit]Endemic to Africa are the familiesArthroleptidae,Astylosternidae,Heleophrynidae,Hemisotidae,Hyperoliidae,Petropedetidae,Mantellidae. Also widespread areBufonidae(Bufo,Churamiti,Capensibufo,Mertensophryne,Nectophryne,Nectophrynoides,Schismaderma,Stephopaedes,Werneria,Wolterstorffina),Microhylidae(Breviceps,Callulina,Probreviceps,Cophylinae,Dyscophus,Melanobatrachinae,Scaphiophryninae),Rhacophoridae(Chiromantis),Ranidae(Afrana,Amietia,Amnirana,Aubria,Conraua,Hildebrandtia,Lanzarana,Ptychadena,Strongylopus,Tomopterna) andPipidae(Hymenochirus,Pseudhymenochirus,Xenopus). The 20022004 Global Amphibian Assessment byIUCN, Conservation International and NatureServe revealed that for only about 50% of the Afrotropical amphibians, there is least concern about their conservation status; approximately 130 species are endangered, about one-fourth of which are at a critical stage. Almost all of the amphibians of Madagascar (238 species[42]) are endemic to that region.[43]The West Africangoliath frogis the largest frog species in the world.Reptiles[edit]

Western green mamba, a venomous snakeThe center ofchameleondiversity is Madagascar. Snakes found in Africa includeatractaspidids,elapids(cobras,Aspidelaps,Boulengerina,Dendroaspis,Elapsoidea,Hemachatus,HomoroselapsandParanaja),causines,viperines(Adenorhinos,Atheris,Bitis,Cerastes,Echis,Macrovipera,Montatheris,Proatheris,Vipera),colubrids(Dendrolycus,Dispholidus,Gonionotophis,Grayia,Hormonotus,Lamprophis,Psammophis,Leioheterodon,Madagascarophis,Poecilopholis,Dasypeltisetc.), thepythonids(Python),typhlopids(Typhlops) andleptotyphlopids(Leptotyphlops,Rhinoleptus).Of thelizards, many species ofgeckos(day geckos,Afroedura,Afrogecko,Colopus,Pachydactylus,Hemidactylus,Narudasia,Paroedura,Pristurus,Quedenfeldtia,Rhoptropus,Tropiocolotes,Uroplatus),Cordylidae, as well asLacertidae(Nucras,Lacerta,Mesalina,Acanthodactylus,Pedioplanis),Agamas,skinksplated lizardsand somemonitor lizardsare common. There are 12 genera and 58 species of Africanamphisbaenians(e.g.Chirindia,Zygaspis,Monopeltis,Dalophia).[44]Several genera oftortoises(Kinixys,Pelusios,Psammobates,Geochelone,Homopus,Chersina), turtles (Pelomedusidae,Cyclanorbis,Cycloderma,Erymnochelys), and three species ofcrocodiles(theNile crocodile,slender-snouted crocodileanddwarf crocodile) are also present.Birds[edit]

African Grey Parrotis native to West-African rainforests.There live (temporarily or permanently) more than 2600birdspecies in Africa (about 1500 of thempasserines).[45]Some 114 of them are threatened species.[46]The Afrotropic has various endemicbirdfamilies, includingostriches(Struthionidae),Mesites,sunbirds,Secretary bird(Sagittariidae),guineafowl(Numididae), andmousebirds(Coliidae). Also, several families of passerines are limited to the Afrotropics. These includerock-jumpers(Chaetopidae),bushshrikes(Malaconotidae),wattle-eyes, (Platysteiridae) androckfowl(Picathartidae). Other common birds includeparrots(lovebirds,Poicephalus,Psittacus), variouscranes(crowned canes,Blue Crane,Wattled Crane),storks(Slaty Egret,Black Heron,Marabous,Abdim's Stork,Shoebill),bustards(Kori Bustard,Neotis,Eupodotis,Lissotis),sandgrouse(Pterocles),Coraciiformes(bee-eaters,hornbills,Ceratogymna),phasianids(francolins,Congo Peafowl,Blue Quail,Harlequin Quail,Stone Partridge,Madagascar Partridge). Thewoodpeckers and alliesincludehoneyguides,African barbets,African Piculet,Ground Woodpecker,DendropicosandCampethera. The birds of prey include thebuzzards,harriers,Old World vultures,Bateleur,Circaetus,Melieraxand others.Trogonsare represented by one genus (Apaloderma).African Penguinis the onlypenguinspecies. Madagascar was once home to the now extinctelephant birds.Africa is home to numeroussongbirds(pipits,orioles,antpeckers,brubrus,cisticolas,negrofinches,olivebacks,pytilias,Green-backed Twinspot,crimson-wings,seedcrackers,bluebills,firefinches,waxbills,amandavas,quailfinches,munias,Weavers,Tit-hylia,Amadina,Anthoscopus,Mirafra,Hypargos,Eremomela,Euschistospiza,Erythrocercus,Malimbus,Pitta,Uraeginthus,Pied Crow,White-necked Raven,Thick-billed Raven,Cape Crowand others). TheRed-billed Queleais the most abundant bird species in the world.Of the 589 species of birds (excluding seabirds) that breed in thePalaearctic(temperate Europe and Asia), 40% spend the winter elsewhere. Of those species that leave for the winter, 98% travel south to Africa.[47]See also:Endemic birds of western and central Africa,Endemic birds of southern Africa.Mammals[edit]

A herd ofAfrican elephantsMore than 1100mammalspecies live in Africa.[48]Africa has three endemic orders of mammals, theTubulidentata(aardvarks),Afrosoricida(tenrecsandgolden moles), andMacroscelidea(elephant shrews). The current research of mammalian phylogeny has proposed anAfrotheriaclade (including the exclusively African orders).[49]TheEast-African plainsare well known for their diversity of large mammals.AfricanSoricomorphainclude theMyosoricinaeandCrocidurinaesubfamilies.Hedgehogsincludedesert hedgehogs,Atelerixand others. Therodentsare represented byAfrican bush squirrels,African ground squirrels,African striped squirrels,gerbils,cane rats,acacia rats,Nesomyidae,springhare,mole rats,dassie rats,striped grass mice,sun squirrels,thicket rats,Old World porcupines,target rats,maned rats,Deomyinae,Aethomys,Arvicanthis,Colomys,Dasymys,Dephomys,Epixerus,Grammomys,Graphiurus,Hybomys,Hylomyscus,Malacomys,Mastomys,Mus,Mylomys,Myomyscus,Oenomys,Otomys,Parotomys,Pelomys,Praomys,Rhabdomys,Stenocephalemysand many others. African rabbits and hares includeriverine rabbit,Bunyoro rabbit,Cape hare,scrub hare,Ethiopian highland hare,African savanna hare,Abyssinian hareand several species ofPronolagus. Among the marine mammals there are several species ofdolphins, 2 species ofsireniansand seals (e.g.Cape fur seals). Of thecarnivoransthere are 60 species, including the conspicuoushyenas,lions,leopards,cheetahs,serval, as well as the less prominentbat-eared fox,striped polecat,African striped weasel,caracal,honey badger,speckle-throated otter, severalmongooses,jackals,civets, etc. The familyEupleridaeis restricted toMadagascarThe African list ofungulatesis longer than in any other continent. The largest number of modernbovidsis found in Africa (African buffalo,duikers,impala,rhebok,Reduncinae,oryx,dik-dik,klipspringer,oribi,gerenuk,true gazelles,hartebeest,wildebeest,dibatag,eland,Tragelaphus,Hippotragus,Neotragus,Raphicerus,Damaliscus). Other even-toed ungulates includegiraffes,hippopotamuses,warthogs,giant forest hogs,red river hogsandbushpigs. Odd-toed ungulates are represented by three species ofzebras,African wild ass,blackandwhite rhinoceros. The biggest African mammal is theAfrican bush elephant, the second largest being its smaller counterpart, theAfrican forest elephant. Four species ofpangolinscan be found in Africa[50]African fauna contains 64 species of primates.[51]Four species of great apes (Hominidae) are endemic to Africa: both species ofgorilla(western gorilla,Gorilla gorilla, and eastern gorilla,Gorilla beringei) and both species ofchimpanzee(common chimpanzee,Pan troglodytes, andbonobo,Pan paniscus).Humansand their ancestors originated in Africa. Other primates includecolobuses,baboons,geladas,vervet monkeys,guenons,macaques,mandrills,crested mangabeys,white-eyelid mangabeys,kipunji,Allen's swamp monkeys,Patas monkeysandtalapoins.Lemursandaye-ayeare characteristic of Madagascar. See alsoLists of mammals of Africa.See also[edit]Africa portal

Afrotropic ecozone List of extinct animals of Africa Fauna of Asia Fauna of Europe Fauna of Australia Fauna of South AmericaReferences[edit]1. Jump up^