I-Dugong - Vala izihlobo zezinkomo zasolwandle ezingasekho kanye nama-manatee akhona njengamanje. Ungukuphela kwelungu lomndeni wakwa-dugong elisindile. Ngokusho kwabanye ochwepheshe, kwaba yena owayeyisibonelo we mermaid wasenganekwaneni. Igama elithi "dugong" laqala ukwenziwa isazi semvelo saseFrance uGeorges Leclerc, uComte de Buffon, ngemuva kokuchaza isilwane saseLeyte Island ePhilippines. Amanye amagama ajwayelekile "yinkomo yasolwandle", "ikamela lasolwandle", "i-porpoise".
Umsuka wezinhlobo nencazelo
Isithombe: Dugong
I-dugong yisilwane esincelisayo esaphila isikhathi eside. Umuntu omdala oqoshiwe uneminyaka engama-73 ubudala. IDugong ukuphela kwezinhlobo ezikhona zomndeni wakwaDugongidae, futhi nolunye lwezinhlobo ezine zohlelo lweSiren, ezinye zakha umndeni wama-manatee. Yaqala ukuhlukaniswa ngo-1776 njengoTrichechus dugon, oyilungu lohlobo lwe-manatee. Kamuva yabonwa njengohlobo lwezinhlobo ezisuka eDugong yiLacépède futhi yahlukaniswa phakathi komndeni wayo.
Ividiyo: Dugong
Iqiniso elithakazelisayo: Ama-dugong nezinye izinhlabamkhosi azihlobene eduze nezinye izilwane ezincelisayo zasolwandle, zihlobene kakhulu nezindlovu. Ama-Dugong nezindlovu babelana ngeqembu le-monophyletic kufaka phakathi i-hyrax ne-anteater, enye yenzalo yokuqala yama-placentals.
Izinsalela zifakazela ukuvela kwama-siren e-Eocene, lapho kungenzeka ukuthi ahlala olwandle lwasendulo lwaseTethys. Kukholakala ukuthi le mindeni emibili esindile ye-siren yahlukana phakathi ne-Eocene, ngemuva kwalokho ama-dugongs kanye nesihlobo sabo esiseduze, inkomo yakwa-Steller, bahlukana nokhokho oyedwa eMiocene. Inkomo yaphela ngekhulu le-18. Izinsalela zamanye amalungu eDugongidae azikho.
Imiphumela yocwaningo lwe-DNA yamangqamuzana ikhombise ukuthi inani labantu base-Asia lihlukile kwabanye abantu bezinhlobo. I-Australia inemigqa emibili yomama ehlukene, omunye wayo uqukethe ama-dugongs avela e-Arabia nase-Afrika. Ukuxubana kwezakhi zofuzo kwenzeke e-Southeast Asia nase-Australia ezungeze iTimor. Abukho ubufakazi obanele bezakhi zofuzo bokubeka imingcele ecacile phakathi kwamaqembu ahlukahlukene.
Ukubukeka nezici
Isithombe: Ibukeka kanjani i-dugong
Ama-dugongs yizilwane ezincelisayo ezinkulu neziminyene ezinezimpiko zangaphambili ezimfishane, ezinjengegwedlo nomsila oqondile noma we-concave osetshenziswa njenge-propeller. Ngokwesakhiwo sayo, umsila uwahlukanisa nezimbadada, lapho inomumo wesigwedlo. Amaphiko eDugong afana namaphiko amahlengethwa, kepha ngokungafani namahlengethwa, ayikho i-dorsal fin. Abesifazane banezindlala ezincelisayo ngaphansi kwamaphiko. Ama-dugongs amadala anesisindo esiphakathi kuka-230 no-400 kg futhi angahluka ngobude ukusuka ku-2.4 kuye ku-4 m.
Isikhumba esijiyile sinombala onsundu ngokumpunga futhi sishintsha umbala lapho kukhula ulwelwe kuso. Ama-Fangs akhona kuwo wonke ama-dugong, kepha abonakala kuphela kwabesilisa abavuthiwe nakwabesifazane asebekhulile. Izindlebe azinawo ama-valve noma ama-lobes, kepha ziyazwela kakhulu. Kukholakala ukuthi ama-dugongs anokuzwela okuphezulu kokuzwa ukukhokhela ukungaboni kahle.
Isifonyo sikhulu impela, siyindilinga futhi siphela ngokukhala. Lesi sikhala siyindebe yemisipha elenga phezu komlomo ogobile futhi isiza i-dugong ukuzifunela utshani basolwandle. Umhlathi olengayo ufaka izingqimba ezikhulisiwe. Ama-sensory bristles amboza izindebe zawo eziphezulu ukusiza ekutholeni ukudla. Ama-bristles nawo amboza umzimba we-dugong.
Iqiniso elithakazelisayo: Okuwukuphela kohlobo olwaziwayo emndenini wakwaDugongidae yiHydrodamalis gigas (inkomo yasolwandle yaseSteller), eyaqothuka ngo-1767, eminyakeni engama-36 nje vo ngemuva kokutholakala kwayo. Zazibukeka ngokufana nombala kuma-dugongs, kepha azidlula kakhulu, ngobude bomzimba obungu-7 kuya ku-10 m nesisindo esingu-4500 kuya ku-5900 kg.
Amakhala abhangqiwe, asetshenziselwa ukungena komoya lapho i-dugong ivela njalo ngemizuzu embalwa, atholakala phezulu kwekhanda. Ama-valve awagcina evaliwe ngesikhathi sokuntywila. I-dugong ine-vertebrae eyisikhombisa yomlomo wesibeletho, i-18 kuya ku-19 yama-vertebrae we-thoracic, ama-vertebrae angama-lumbar amane kuya kwamahlanu, okungenani i-sacral eyodwa, kanye ne-28 kuya ku-29 ye-caudal vertebrae. I-scapula imise okwenhla, ama-clavicles awekho nhlobo, ngisho nethambo le-pubic alikho.
Ihlala kuphi i-dugong?
Isithombe: Marine Dugong
Ububanzi bezindawo zokuhlala i-dugong buhlanganisa imingcele yamazwe nezindawo ezingama-37 ezisuka eMpumalanga Afrika ziye eVanuatu. Ibamba amanzi asogwini afudumele asuka oLwandlekazi iPacific aye ogwini olusempumalanga ye-Afrika, okubalelwa ku-140,000 km ngasogwini lolwandle. Kukholakala ukuthi ibanga labo langaphambili belihambelana nobubanzi botshani basolwandle bemindeni iRestestovy neVodokrasovye. Usayizi ogcwele wobubanzi bokuqala awaziwa kahle.
Okwamanje, ama-dugongs ahlala emanzini asogwini ala mazwe:
- Australia;
- ESingapore;
- ECambodia;
- China;
- IGibhithe;
- India;
- I-Indonesia;
- EJapan;
- IJordani;
- IKenya;
- Madagascar;
- IMauritius;
- EMozambique;
- EPhilippines;
- ESomalia;
- ISudan;
- Thailand;
- IVanuatu;
- IVietnam, njll.
Ama-dugong atholakala engxenyeni enkulu yogu lwala mazwe, nenani elikhulu ligxile ezindaweni ezivikelwe. I-dugong ukuphela kwesilwane esincelisayo esidla izilwane zasolwandle kuphela, ngoba zonke ezinye izinhlobo zama-manatee zisebenzisa amanzi ahlanzekile. Inani elikhulu labantu nalo liyatholakala eziteshini ezibanzi nezingajulile ezizungeze iziqhingi ezisogwini, lapho amadlelo alga ejwayelekile khona.
Imvamisa, zitholakala ekujuleni okungaba ngamamitha ayi-10, yize ezindaweni lapho ishalofu lezwekazi lihlala lingajulile, ama-dugong ahamba ngaphezu kwamakhilomitha ayi-10 ukusuka ogwini, ehlela kuma-37 m, lapho kwenzeka khona utshani basolwandle olujulile. Amanzi ajulile anika isiphephelo emanzini apholile asogwini ebusika.
Manje uyazi lapho kuhlala khona i-dugong. Ake sithole ukuthi lesilwane sidlani.
Yini edliwa yi-dugong?
Isithombe: Dugong ovela kwiRed Book
Ama-Dugongs yizilwane ezincelisayo zasolwandle ezidla kuphela futhi adla ulwelwe. Lawa ikakhulukazi ama-rhizomes otshani basolwandle acebile ngama-carbohydrate, asuselwa enhlabathini. Kodwa-ke, zondla ngaphezu kwezingxenye zezitshalo ezingaphansi komhlaba, ezivame ukudliwa ziphelele. Imvamisa zidla ngamamitha amabili kuya kwayisithupha ukujula. Kodwa-ke, imisele ejwayelekile eyisicaba noma imihosha abayishiyayo lapho kudla khona nayo itholakele ekujuleni kwamamitha angama-23. Ukufika ezimpandeni, ama-dugongs athuthukise amasu akhethekile.
Bafinyelela ezimpandeni ngokulandelana okulandelayo kokunyakaza:
Njengoba udebe olungaphezulu olubunjiwe ngehhashi luqhubeka, ungqimba oluphezulu lwenzika luyasuswa,
khona-ke izimpande ziyakhululwa emhlabeni, zihlanzwe ngokuqhaqhazela zidliwe.
Bancamela utshani obuncane besilwandle obuvame ukuvela esigabeni uHalophila noHalodule. Yize zine-fiber encane, ziqukethe izakhamzimba eziningi ezincibilika kalula. Kuphela ulwelwe oluthile kuphela olulungele ukusetshenziswa ngenxa yokudla okukhethekile kakhulu kwezilwane.
Iqiniso elithakazelisayo: Kunobufakazi bokuthi ama-dugongs anomthelela omkhulu ekushintsheni kokwakheka kwezinhlobo zezinhlobo ze-algae ezingeni lendawo. Amathrekhi wokondla atholakale kumamitha angama-33, kwathi ama-dugong abonwa ngamamitha angama-37.
Izindawo ze-algae lapho ama-dugong avame ukondla khona, ngokuhamba kwesikhathi, izitshalo ezinothe nge-nitrogen eziningi ngokwengeziwe. Uma insimu ye-algae ingasetshenziswa, inani lezinhlobo ezicebile ze-fiber liyanda futhi. Yize izilwane zicishe zidle kakhulu, kwesinye isikhathi zidla izinambuzane ezingenamgogodla: i-jellyfish nama-molluscs.
Kwezinye izingxenye eziseningizimu ye-Australia, babheke ngenkuthalo ama-invertebrate amakhulu. Kodwa-ke, lokhu akujwayelekile kubantu abavela ezindaweni ezishisayo, lapho izinambuzane ezingenamgogodla zingazidli nhlobo. Ziyaziwa ngokubeka inqwaba yezitshalo endaweni eyodwa ngaphambi kokuba zidle.
Izici zobuntu nendlela yokuphila
Isithombe: I-dugong ejwayelekile
I-dugong iyinhlobo yezenhlalo kakhulu, etholakala ngamaqembu abantu abayi-2 kuye kwangama-200. Amaqembu amancane ngokuvamile aqukethe amapheya omama nengane. Yize imihlambi yama-dugong angamakhulu amabili ibonakele, ayijwayelekile kulezi zilwane njengoba amasimu algae engakwazi ukuxhasa amaqembu amakhulu isikhathi eside. Ama-Dugong ayizinhlobo ezihamba phambili. Bangathutha amabanga amade ukuthola umbhede othile wezimila zasolwandle, kodwa futhi bangahlala endaweni efanayo impilo yabo yonke lapho ukudla kwanele.
Iqiniso elithakazelisayo: Izilwane ziphefumula njalo ngemizuzwana engama-40-400 ngenkathi zidla. Njengoba ukujula kukhuphuka, ubude besikhathi sokuphefumula nabo buyakhuphuka. Ngezinye izikhathi zibheka nxazonke ngenkathi ziphefumula, kepha imvamisa kuphela amakhala abo aphuma emanzini. Imvamisa, lapho bekhipha umoya, benza umsindo ongazwakala kude.
Ukuhamba kuncike ebuningini naseqophelweni lomthombo wabo oyinhloko wokudla, ulwelwe. Uma izimfundamakhwela zasendaweni seziqedile, zibheka okulandelayo. Njengoba ama-dugongs atholakala emanzini anodaka, kunzima ukuwagcina ngaphandle kokuwaphazamisa. Uma ukuthula kwabo kwengqondo kuphazamisekile, basuka ngokushesha ngasese emthonjeni.
Izilwane zinamahloni, futhi ngendlela ecophelelayo, zihlola i-diver noma isikebhe kude kakhulu, kepha ziyanqikaza ukusondela. Ngenxa yalokhu, kuncane okwaziwayo ngokuziphatha kwama-dugongs. Baxhumana ngokutshiyoza, ngopende nangekhwela. Ngale misindo, izilwane zixwayisa ngezingozi noma zigcine ukuthintana phakathi kwezinyane nomama.
Isakhiwo senhlalo nokuzala
Isithombe: Dugong Cub
Ukuziphatha kokukhwelana kuyahlukahluka ngokuya ngendawo. Ama-dugong wesilisa avikela izindawo zawo futhi ashintshe indlela aziphatha ngayo ukuheha abesifazane. Ngemuva kokuheha abesifazane, ama-dugong wesilisa adlula ezigabeni eziningana zokuqhudelana. Amaqembu abesilisa alandela insikazi eyodwa ngomzamo wokukhwelana.
Isigaba sokulwa siqukethe amanzi atshazayo, iziteleka zemisila, ukuphonsa umzimba kanye nokuvuza. Kungaba nodlame, njengoba kufakazelwa yizibazi ezibonwa emzimbeni wabesifazane nakwabesilisa abancintisanayo.
Ukukhwelana kwenzeka lapho owesilisa oyedwa ehambisa insikazi ngezansi, kuyilapho abesilisa abaningi beqhubeka nokubanga leso sikhundla. Ngenxa yalokho, owesifazane uhlangana izikhathi eziningana nabesilisa abancintisanayo, okuqinisekisa ukukhulelwa.
Ama-dugongs abesifazane afinyelela ekuvuthweni ngokocansi eneminyaka engu-6 ubudala futhi angaba nenkonyane labo lokuqala phakathi kweminyaka eyisithupha kuya kwengu-17 ubudala. Abesilisa bafinyelela ekuvuthweni ngokocansi phakathi kweminyaka eyi-6 nengu-12 ubudala. Ukuzala kungenzeka unyaka wonke. Izinga lokuzalisa ama-dugong liphansi kakhulu. Zikhiqiza inyosi eyodwa njalo eminyakeni eyi-2,5-7 kuye ngendawo. Lokhu kungabangelwa yisikhathi eside sokukhulelwa, okuyizinyanga eziyi-13 kuye kwezingu-14.
Iqiniso elithakazelisayo: Omama namathole bakha isibopho esisondelene esiqiniswa isikhathi eside sokuncela ebeleni, kanye nangokuthintwa ngokomzimba ngesikhathi sokubhukuda nokuncelisa. Owesifazane ngamunye uchitha cishe iminyaka eyisithupha nengane yakhe.
Lapho zizalwa, amawundlu anesisindo esingaba ngu-30 kg, anobude obungu-1.2 m. Asengozini enkulu yezilwane ezizingelayo. Amathole anceliswa ibele izinyanga eziyi-18 noma ngaphezulu, ngalesi sikhathi ahlala esondelene nonina, evame ukugingqika emhlane wakhe. Yize amawundlu e-dugong angadla utshani basolwandle cishe ngokushesha ngemuva kokuzalwa, isikhathi sokuncela sibavumela ukuba bakhule ngokushesha okukhulu. Lapho sebekhulile, bashiya omama babo babheke abangaba ngabalingani babo.
Izitha zemvelo ze-dugong
Isithombe: Dugong
Ama-dugong anezilwane ezimbalwa ezidla imvelo. Usayizi wazo omkhulu, isikhumba esiqinile, ukwakheka kwamathambo aminyene, nokuqina kwegazi ngokushesha kungasiza ekuvikeleni. Yize izilwane ezinjengezingwenya, imikhomo ebulalayo noshaka zibeka engcupheni izilwane ezisencane. Kubhalwe ukuthi i-dugong eyodwa ishonile ngokulimala ngemuva kokubethelwa nge-chute.
Ngaphezu kwalokho, ama-dugongs avame ukubulawa ngabantu. Zizingelwa ezinye izinhlanga e-Australia naseMalaysia, zibanjwa ngamanetha e-gill kanye namanetha anezikhala abekwe ngabadobi, futhi zichayelwa abazingeli abazingela ngokungemthetho ezikebheni nasemikhunjini. Baphinde balahlekelwe yindawo yabo yokuhlala nezinsizakusebenza ngenxa yemisebenzi yabantu engenzi lutho.
Izilwane ezidumile zama-dugong zifaka:
- oshaka;
- izingwenya;
- imikhomo yokubulala;
- abantu.
Icala laqoshwa ngesikhathi iqembu lama-dugongs ngokuhlanganyela likwazile ukuxosha ushaka ebazingela. Futhi, isibalo esikhulu sokutheleleka kanye nezifo zesinambuzane siyazithinta lezi zilwane. Amagciwane atholakalayo afaka i-helminths, i-cryptosporidium, izinhlobo ezahlukahlukene zezifo ezibangelwa amagciwane, kanye nezinye izimuncagazi ezingaziwa. Kukholakala ukuthi ama-30% okufa kwe-dugong kubangelwa izifo ezibahlaselayo ngenxa yokutheleleka.
Inani labantu kanye nesimo sezinhlobo
Isithombe: Ibukeka kanjani i-dugong
Amazwe / izindawo ezinhlanu (Australia, Bahrain, Papua New Guinea, Qatar kanye ne-United Arab Emirates) zigcina abantu abaningi base-dugong (ngaphakathi kwezinkulungwane) namashumi ezinkulungwane enyakatho ye-Australia. Iphesenti labantu abavuthiwe liyahlukahluka phakathi kwamaqembu amancane ahlukene, kepha liyashintshashintsha kwenye indawo phakathi kuka-45% no-70%.
Imininingwane yofuzo kumasheya e-dugong kukhawulwe kakhulu esifundeni sase-Australia. Umsebenzi wakamuva osuselwa ku-DNA ye-mitochondrial ukhombisa ukuthi inani labantu base-Australia dugong aliyona i-panimia. Inani labantu base-Australia lisenokuhlukahluka okuphezulu kofuzo, okukhombisa ukuthi ukwehla kwesibalo sabantu kwakamuva akukakaboniswa kusakhiwo sezakhi zofuzo.
Imininingwane eyengeziwe esebenzisa izimpawu ezifanayo zofuzo ikhombisa umehluko omkhulu phakathi kwabantu baseningizimu nenyakatho yeQueensland. Izifundo zokuqala zofuzo zabantu be-dugong ngaphandle kwe-Australia ziyaqhubeka. Ukuqaphela kuqopha umehluko oqinile wesifunda. Abantu base-Australia bahlukile kwabanye abantu entshonalanga ye-Indian Ocean ngokufana futhi banomkhawulo wokwehlukahluka kofuzo.
Kunozalo olukhethekile eMadagascar. Isimo esifundeni se-Indo-Malay asicaci, kepha kungenzeka ukuthi imigqa eminingana yomlando ixutshwe lapho. I-Thailand iyikhaya lamaqembu ahlukahlukene okungenzeka ahlukane phakathi nokushintshashintsha kwezinga lolwandle iPleistocene, kepha manje angaxubana ngokwendawo kulezi zifunda.
Unogada waseDugong
Isithombe: Dugong ovela kwiRed Book
Ama-Dugong abhalwe njengasengozini futhi abhalwe ku-Appendix I we-CITES. Lesi simo sihlotshaniswa ngokuyinhloko nokuzingela nemisebenzi yabantu. Ama-Dugong ngengozi abanjwa emanetheni anezinhlanzi noshaka futhi afe ngenxa yokushoda komoya-mpilo. Balimala nezikebhe nemikhumbi. Ngaphezu kwalokho, ukungcoliswa kwezilwandle kubulala ulwelwe, oluthinta kabi ama-dugong. Ngaphezu kwalokho, izilwane zizingelwa inyama, amafutha nezinye izingxenye ezibalulekile.
Iqiniso elithakazelisayoAbantu baseDugong abakwazi ukululama ngokushesha ngenxa yezinga labo lokukhiqiza eliphansi kakhulu. Uma wonke ama-dugongs abesifazane kubantu ekhuliswe ngamandla aphelele, isilinganiso esiphezulu abantu abangakhuphuka singama-5%. Lesi sibalo siphansi, yize bephila isikhathi eside nokufa okuphansi kwemvelo ngenxa yokungabi bikho kwezidliwayo.
I-Dugong - kukhombisa ukwehla okungaguquki kwamanani. Ngaphandle kokuthi amanye amasayithi avikelwe enzelwe bona, ikakhulukazi ngasogwini lwase-Australia. Lezi zindawo ziqukethe inqwaba yezinhlanzi zasolwandle nezimo ezifanele zokuhlala ama-dugong, njengamanzi angajulile nezindawo zokuzala. Kwenziwe imibiko yokuhlola ukuthi izwe ngalinye ebangeni le-dugong kumele lenzeni ukulondoloza nokuvuselela lezi zidalwa ezinomusa.
Usuku lokushicilelwa: 08/09/2019
Idethi ebuyekeziwe: 09/29/2019 ngo-12: 26
