Amabele Amaningi: Izimpawu Ezixubekile Kwezocansi Nomama

Ngemuva kokuphothula i-Ph.D. Yami Eminyakeni engama-50 edlule, ngahola umkhankaso we-Oxford University ngaya eMadagascar ephelezelwa ngabane abafundela iziqu. Kwesinye isikhathi, sihamba ezindaweni ezikude eLand Rover yethu, besizomangala ngezilazi zasendaweni ezigeza ngama-torsos angenalutho. Lapho besibona sidlula, babenamahloni bewela izingalo zabo phezu kwamabele abo. Ngokushesha safunda ukundiza ngamandla, okwathi lapho izintambo zaphakamisa intshiseko ngentshiseko. Sajabula kakhulu lapho sibonisa ubungane ngesizotha.

Amabele ngokuqinisekile ayakhanga kwabesilisa, ikakhulukazi abantu abadala abasha abavela emasikweni lapho abesifazane bafundiswa khona ukugcina amabele abo emboziwe. Kukhuliswe ngale ndlela, ubuhlakani buvame ukusabela ngolaka lapho bebona owesifazane encelisa obala. Amasiko alindele ukuthi abesifazane bagqoke ngokuphelele agcizelela ukungaqondakali ngamabele njengemithombo yobisi lomama noma izimpawu zocansi. Ngakho-ke kubalulekile emibonweni yokuvela kwemvelo mayelana nemisebenzi yamabele ukuze ihlolwe kumasiko wonke. Iningi lezifundo eziningi ezikhangayo zamabele zibhekise kubantu abanesikhumba esimhlophe — iningi labo abathola iziqu eziphansi — kubantu abasebenza ngezimboni.

Umlando wemvelo wamabele

Imibele efana nemibhobho enikezwa ngamapayipi avela kwizindlala zobisi, ejwayelekile kuwo wonke ama-marsupials abesifazane kanye nama-placentals, konke okudingekayo ukuncela. Okujwayelekile kwesilwane esincelisayo ukuncelisa izingono , hhayi ukuncelisa. Noma kukhuliswa izingane, iningi likhombisa ukuvuvukala okuncane ngoba akubalulekile ekukhiqizeni ubisi noma ukuncela. Amabele we-globular abesifazane avuvuke unomphela ayindlala emangazayo. Ezilwaneni ezimbalwa ezincelisayo, ikakhulukazi izindlovu, amabele ayakhukhumala ekukhulelweni sekwephuzile ukulungiselela ukuncela kodwa ngokuvamile kuyancipha ngemuva kokulunyulwa. Isifuba sibuye sihlale siyisicaba kuze kufike ukukhulelwa kokuqala ezimpandeni ezingezona ezomuntu, kepha amabele angabonakala ngokuvuvukala kukho konke ukuncela, ikakhulukazi ezinkawini ezinkulu. Kwesinye isikhathi, amabele ahlala evuvukele phakathi kokukhulelwa kwabesifazane asebekhulile abakhulise izinsana eziningana.

Enye into ebonakala ingafani nesifuba somuntu yi- areola —Indawo emnyama yesikhumba ezungeze ingono. Umbele uthwala uhla oluyindilinga lwemigudu engu-15-20 evula ubisi ngesikhathi sokuncela, kuyilapho i-areola iba nomthelela omkhulu emzimbeni. Ngokuya ngombala wesikhumba ojwayelekile, umbala oyisisekelo we-areola uyahlukahluka kusuka kokuphinki okukhanyayo kuye konsundu. Kunoma imuphi umuntu wesifazane ngamunye, futhi kuyehluka kuye ngokuphendula ekushintsheni kwe-hormonal kumjikelezo wokuya esikhathini, ukukhulelwa nokuguga.

Noma kuqhathaniswa nezinkawu ezinkulu, amabele omuntu anezinye izici ezimbili eziphawulekayo: okokuqala, ukuqala kokuvuvukala kwamabele unomphela inguquko yokuqala esobala entombazaneni ngesikhathi sokuthomba, eminyakeni eminingana ngaphambi kokuba incelise usana kuqala. Okwesibili, asikho esinye isilwane esincelisayo esinamabele amakhulu kangako uma siqhathaniswa nosayizi womzimba.

Kuchaza amabele avuvukile

Kungani owesifazane enamabele aqhamukayo? Uma sezithuthukile, zinomgogodla wezicubu ezijwayelekile ezikhiqiza ubisi lwe-mammalian ezizungezwe amadiphozithi amaningi. Lokhu kuqanjwa okubili kubonakala ngokusobala ngesikhathi sokuthomba lapho zombili izindlala zobisi namafutha anqwabelene ekhula ngokulandelana. Ngakho-ke indawo yokuqala enengqondo yokuchaza usayizi webele kulindelekile ukuthi amabele amakhulu akhiqiza ubisi oluningi.

Eqinisweni, ubisi alutholakali kuphela noma lutholakala ikakhulukazi ekufakeni amafutha emabeleni. Owesifazane osancela usana kudingeka aqoqe ukugcinwa kwamafutha emzimbeni wakhe wonke, hhayi kusuka emabeleni kuphela. Yize abesifazane benamabele amakhulu ngokuphawulekayo uma kuqhathaniswa nezinye izilwane ezincelisayo, ngokwesilinganiso womabili ndawonye aqukethe ngaphansi kuka-4% wamafutha omzimba esewonke. Ngaphezu kwalokho, ngokukhethekile phakathi kwezilwane ezincelisayo, ubulili buyahluka ngokuhlukile: Abesifazane bathwala amafutha amaningi kakhulu, agxile ezindaweni ezithile ezinjengezinqe namathanga.

Iphepha lika-2018 likaHerman Pontzer elibukeza imininingwane ngabazingeli-abaqoqi linikeze imininingwane eningiliziwe ngokwakhiwa komzimba kweHadza yaseTanzania. Kubantu abadala abaphakathi kweminyaka engama-20 nengama-80 ubudala, amafutha enza u-25% wesisindo somzimba kwabesifazane kodwa u-10% kuphela kwabesilisa. Umzimba wesifazane o-Hadza ongamakhilogremu ayi-100 ophilile yingakho uqukethe amakhilogremu angama-25 amafutha, okungaphansi kwephawundi ngokuvamile okungaqukethwe kuwo womabili amabele ahlanganisiwe (ngaphandle kokukhulelwa noma ukuncela).

Ngabe amabele amakhulu akhiqiza ubisi oluningi?

Kudala kwaziwa ukuthi ukukhiqizwa kobisi lowesifazane akuhlobene kakhulu nosayizi webele. Ephepheni elicashunwe kakhulu lango-1954, uFrank Hytten wabika imiphumela yocwaningo olwenziwe kahle ngosayizi webele lomuntu maqondana nokuncela. Imininingwane eqoqwe kwabesifazane baseScotland abangaphezu kwekhulu ngesonto ngemuva kokuzalwa ekuqaleni ibibonakala ikhombisa ubudlelwane obuthakathaka kodwa obubalulekile phakathi kosayizi webele nokukhishwa kobisi. Kodwa-ke, kwabesifazane abayishumi nanye uHytten uphinde walinganisa usayizi webele ngenyanga yesithathu yokukhulelwa ukubala inani lebele ukukhulisa lokho kwenzeka ngosuku lwesikhombisa ngemuva kokuzalwa. Ubukhulu bokukhuliswa abukhombisanga ukuxhumana nokuqala kosayizi webele, obehluka kakhulu phakathi kwabesifazane, kepha bewuhlobene ngokuqinile nokukhishwa kobisi. Lokhu kunengqondo ngoba kwabesifazane abangakhulelwe, nabangancelisi izindlala zobisi zibala isilinganiso sobukhulu besifuba, kuyilapho usayizi webele ukwanda ngesikhathi sokukhulelwa ikakhulu kukhombisa izicubu eziyindlala ezingezekile.

Ngokudabukisayo, kube nokulandelwa okuncane esifundweni sikaHytten. Kepha iphepha lika-2014 likaChristian Bayer kanye nozakwabo linikeze ubufakazi obubalulekile obusekelayo. Amanani amabele ahlolwe kwabesifazane abayikhulu ngezigaba ezimbili zokukhulelwa, okokuqala phakathi nesonto le-12 futhi nangeviki lama-40, ngaphambi nje kokuzalwa. Phakathi kwalezi zigaba ezimbili, umthamo omaphakathi webele elilodwa ukhuphukile usuka ku-420 ml (ama-ounces ayi-14 oketshezi) uye ku-515 ml (171/2 ounces fluid). Kepha, njengombiko kaHytten, ukwanda ngosayizi webele kuhlukahluka kakhulu kungakhathalekile ivolumu yokuqala.

Ukuhluka kwesayizi webele

Ngokweqile, usayizi webele ojwayelekile wehluka kakhulu ngaphakathi naphakathi kwabantu. Phakathi kwezinye izinto, lokhu kubalulekile kodokotela abahlinzayo lapho kwakhiwa kabusha amabele ngemuva kokukhishwa kwezicubu noma ukuguqula usayizi webele ngokokuhlobisa. Kuyabakhathaza nabakhiqizi bezingubo, ikakhulukazi uma bebandakanyeka emazweni omhlaba.

Ngokumangazayo, idatha eyisisekelo ngokuhluka kosayizi webele kwabesifazane ayivamile ukuhlanganiswa. Okuhlukile okuphawulekayo yiphepha lika-2017 likaCeleste Coltman nozakwabo, abalinganisa amavolumu amabele kwesobunxele nangakwesokudla abesifazane base-Australia abangama-356 abaneminyaka eyi-18 kuya kwengama-84. Ukuhluka bekukukhulu, kusuka ku-48 ml (11/2 ounces fluid) kuya ku-3100 ml (61/2 pints). Ngamabele angakwesokunxele noma kwesokudla (imvamisa afana nosayizi), inani eliphakeme lalizungeze ama-400 ml (ngaphansi kwepinti). Kuyathakazelisa ukuthi amavolumu amabele awakhombisanga ukusatshalaliswa kwensimbi kuzungeze inani elijwayelekile kepha kwakucijwe kahle. Le patheni- nayo ebonwa namanye amasethi wedatha — kufanele ikhunjulwe lapho iphakamisa ukuthi ukukhetha kwemvelo kukhetha usayizi ofanele.

Ngaphezu kokwehlukahluka okubanzi kosayizi besifuba ngaphakathi inani labantu, amanani aphakathi nawo ahluka kakhulu phakathi abantu. Kepha imininingwane ebhalwe kahle ayindlala. Umthombo okuyiwona kuphela ocashunwe kabanzi yiphepha lika-2013 likaJohn Anderson nozakwabo ephephabhukwini elingasasebenzi. Leli phepha likhombisa ukuthi abesifazane base-Afrika nase-Asia bavame ukuba namabele amancane, kuqhathaniswa nabesifazane baseYurophu, eNingizimu Melika futhi, ikakhulukazi, eNyakatho Melika. Noma iyiphi incazelo ehlongozwayo yokuziphendukela kwemvelo kufanele ibhekane nalokhu kwehluka okubikiwe okuphawulwe ngosayizi wamabele ophakathi kwabantu.

Amabele njengamazibuthe abonakalayo

Ukuvuvukala unomphela kwesifuba somuntu kusukela ekuthombaneni kuya phambili akudingeki ekukhiqizeni ubisi noma ukuncela, ngakho-ke kusebenza omunye umsebenzi. Ngo-1987, esihlokweni esasinesihloko esibi esithi "Amabele omuntu, imicabango engaxhasiwe isibuyekeziwe ,’ UTim Caro ubhale ezinye izincazelo eziyisishiyagalombili zokuvela kwamabele avuvuke unomphela. Eminyakeni engamashumi amathathu kamuva, incazelo egculisayo isalokhu ingekho. Noma kunjalo iphuzu elilodwa licacile: amabele aheha ukunakwa.

Emaphepheni amabili ngo-2010 nango-2011, uBarnaby Dixson nozakwabo babika besebenzisa ithuluzi lokulandela iso ukuthola ukuthi iso lendoda lihlala kuphi, nini futhi isikhathi esingakanani lapho libuka umzimba wowesifazane. Bavivinye amashumi amathathu amadoda akhishwe e-Europe anezithombe ezahlukahlukene zabesifazane ezazivela ngaphambili, konke kuthathwe esithombeni sokuqala sokuqala sowesifazane onqunu kepha kukhishwe ikhompiyutha ukwehluka ngosayizi webele (omncane, ophakathi, omkhulu). Cishe uhhafu wabesilisa abahloliwe babheka amabele esifazane kuqala, bathathe okungaphansi kwesihlanu komzuzwana ukwenza njalo, kanti owesithathu waqala okhalweni kanti oyedwa kwabayisikhombisa ngendawo yasesithombeni noma emathangeni. Uyedwa kuphela kwabesilisa abangu-16 obheke ubuso bowesifazane kuqala. Kukho konke ukuhlolwa kwemizuzwana emihlanu, amadoda abheka amabele kaningi futhi nangezikhathi ezinde.

Ukuyisa izinto phambili

Kuningi okusazoshiwo ngokuhlolwa kwezincazelo ezihlongozwayo zamabele womuntu avuvukile, kepha lokho kudinga ukuthunyelwa kwesibili kwebhulogi. Okwamanje, kungaphethwa ngokuthi amabele abantu anezici ezahlukile, ikakhulukazi ezimakwe ukwehla kwamandla emali kusukela ekuthombaneni. Mayelana nokusebenza komzimba, kubonakala kucace ukuthi usayizi webele ngaphambi kokukhulelwa awubalulekile. Okubalulekile ekukhiqizeni ubisi amabele ukukhulisa ngesikhathi sokukhulelwa. Amabele ngokusobala adonsa ukunaka kwamadoda, kepha awakhombisi ngokuthembekile ukukhiqizwa kobisi. Ukuchazwa okuhlukile kuyadingeka, kukhunjulwa ukuthi noma ikuphi ukucatshangelwa kokuvela kwemvelo kuzoba ngumsolwa ngaphandle kokuqhathanisa okusebenzayo kwamasiko.

Qaphela : Ngibonga kakhulu u-Alan noBarnaby Dixson ngokuvumela ukusetshenziswa kwamanani aguquliwe asuka emaphepheni abo amahle, naku-Alan ngokunikeza imibono yokusiza kakhulu.

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