Izinkalo, amaHips kanye ne-Sexy Hourglass Shape

Izifundo eziningana - ikakhulukazi zabesifazane futhi kuyaqabukela kwabesilisa - zizamile ukukhomba ubujamo bomzimba ukuthi amazinga wobulili obuhlukile akhanga. Inhloso ejwayelekile ukukhomba izici ezithile ezingashintsha njengezimpawu ezibonisa amandla okuzala womlingani. Kepha kungenzeka yini ukuthi izinkomba ezilula kangaka zibe okhiye benqubo eyinkimbinkimbi yokuzikhethela kozakwethu?

Izimpawu zokuqomisana

Ngikhumbula kahle izinkulumo zokuziphatha ngumeluleki wami wangaphambili uNiko Tinbergen eminyakeni engamashumi amahlanu edlule. Okwakuthokozisa ngokukhethekile kwakuwucwaningo lwakhe lokuphola ngokuqomisana ngenhlanzi ephansi, i-stickleback enezinhlaka ezintathu. Lapho kuqala inkathi yokuzalanisa, owesilisa osekhulile ubeka indawo emanzini angajulile futhi akhe isidleke esifana nomhubhe ngezinsalela zezimila phezu komgodi omncane. Kunoma yimuphi owesifazane odlulayo onesisu esivuvuke iqanda, wenza umdanso we-zig-zag, aqale ngokubhukuda abheke ngakuye bese emholela esidlekeni. Eyensikazi iyabhukuda ingene emhubheni, ifake amaqanda amaningi, bese kuthi eyesilisa ilandele ukuwafaka umquba. Ngemuva kwalokho, uphephetha amanzi esidlekeni ubusuku nemini ukuze avuse amaqanda.

Lokhu kulandelana kokuthandana kwaholela ekutheni uTinbergen abone isikhuthazi sesibonakaliso - isignali elula evusa impendulo ethile. I-stickleback yeduna endaweni yakhe yokuzalanisa iba nombala obomvu ogqamile esifubeni sayo, okuheha abesifazane futhi kubangele ubudlova obuvela kwamanye amaduna. Ngokufanayo, isisu sowesifazane esigcwele iqanda siyisikhuthazo sesibonakaliso esivusa ukuqomisana kowesilisa. Esebenzisa izigaxa ezingahluziwe eziphindaphinda izinto ezibalulekile kuphela, uTinbergen ukhombisile ukuthi iduma "elinomphimbo obomvu", elihanjiswe ngemfashini ye-zig-zag, liheha owesifazane esidlekeni, kanti iduma "elinsikazi" elivuvukile elinamalungu livusa ukuqomisana kwabesilisa. Ngempela, uTinbergen ukhombisile ukuthi isignali enehaba - isikhuthazi esingaphezu kwamandla - ingasebenza kakhulu. Isibonelo, "owesilisa" wesidoda onesifuba esibomvu esingaphezu kwesivamile wakhipha ubudlova obunamandla obuvela emadodeni okuhlolwa.

Ukukhipha amasiginali kubantu besifazane?

Yize ukuziphatha komuntu kuyinkimbinkimbi ngokwedlulele, abacwaningi bafune izimpawu ezifanayo kwabesifazane. Esivivinyweni esijwayelekile sokuhlolwa kucelwa ukukala ukuheha kwezithombe ezi-2-dimensional. Ukulandela amaphepha amabili weseminal kaDevendra Singh ngo-1993, ukugxila kugxile kubukhulu obuphakathi kwesinqe nobubanzi besinqe kuhlaka lomzimba wowesifazane, kukhombisa ukusatshalaliswa kwamafutha omzimba. Isinqe: ama-hip ratios (ama-WHRs) aqubeka kancane phakathi kobulili. Amabanga ajwayelekile anempilo ayi-0.67-0.80 yabesifazane be-premenopausal kanye no-0.85-0.95 wabesilisa. Ngokuqaphela ukuthi "yonke imibono yezinketho zomlingani womuntu ngokuya ngemigomo yokuziphendukela kwemvelo icabanga ukuthi ukuheha kunikeza umkhondo onokwethenjelwa kunani lokuzala lowesifazane .........", izifundo zokuqala zikaSingh zikhombise ukuthi amadoda ajwayele ukulinganisa amanani abesifazane ane-WHR ephansi ezungezile 0.7 ikhanga kakhulu kunanoma yimaphi amanani aphezulu.

Ukwenza ihaba ngokweqile kwesimo se-hourglass kuma-corsets adumile we-19th Century "wasp-waist" kuye kwahunyushwa njengesikhuthazo esingajwayelekile esithuthukisa ubuhle besifazane. Ngokudabukisayo, nokho, imifanekiso ehlanganisiwe ye- "Venus" evela ePalaeolithic - enezilinganiso ze-WHR ezungeze i-1.3 - ihunyushwe ngendlela efanayo.

Izifundo ezalandela zikuqinisekisile kabanzi ukuthi amadoda ajwayele ukukala ukwakheka komzimba wabesifazane nge-WHR phakathi kuka-0.6 no-0.8 njengokukhanga kakhulu. Ngaphezu kwalokho, ukuthandwa kwe-WHR ephansi kuyavumelana kubantu abaningi namasiko ahlukahlukene. Ku- Ubulili be-Primate , Amarekhodi ka-Alan Dixson akhetha amanani we-WHR angu-0.6 kubafundi baseyunivesithi baseChina nabazingeli baseHadza baseTanzania, ama-0.7 amaNdiya nabaseMelika baseCaucasus, no-0.8 wabesilisa eBakossiland, eCameroon. Ephepheni lika-2010, uBarnaby Dixson nozakwabo basebenzise ukulandela iso ukuhlola okuthandwa ngabesilisa nge-WHR yabesifazane nosayizi webele. Baqopha ukulungiswa kokuqala nezikhathi zokuhlala kwamadoda abuka izithombe ezibekwe phambili zowesifazane ofanayo ezenzelwe ukwehluka ku-WHR (0.7 noma 0.9) nosayizi webele. Kungakapheli ama-millisecond angama-200 okuqala kokuhlolwa ngakunye, kungaba amabele noma okhalweni kuveze ukulungiswa kokuqala kokubuka. Izithombe ezine-WHR ye-0.7 zilinganiswe njengezikhanga kakhulu, ngaphandle kosayizi webele.

Kokuxhumana kuka-1998, nokho, uDouglas Yu noGlenn Shepard babika ukuthi ukuthanda abesilisa kwabesifazane abane-WHR ephansi kungahle kungabi ngokwesiko jikelele. Ngokuqaphela ukuthi "lonke usiko oluhloliwe kuze kube manje seludalulwe kumthelela ongaxaka wabezindaba zasentshonalanga", laba babhali bahlole okuthandwa ngabantu abakude ngokwamasiko abantu bomdabu baseMatsigenka baseningizimu-mpumalanga yePeru. Amadoda aseMatsigenka ancamela izinhlaka ezine-WHR ephezulu, echaza lokhu okucishe kube yishubhu njengokunempilo. Ekuvivinyweni kwabanye abantu bendawo ku-gradient yokwanda kwentshonalanga, izintandokazi ze-WHR ziqhubeka ngokuya kulabo ababikwe emazweni asentshonalanga. U-Yu noShepard baphethe ngokuthi izivivinyo zangaphambilini "kungenzeka ukuthi zibonise kuphela ukusabalala kwemithombo yezindaba yasentshonalanga". Kepha lolu cwaningo luyinkinga ngoba abesilisa bacelwe ukuthi balinganise izinhlaka ezisentshonalanga ezifundweni zokuqala zikaSingh kunamanani afanele ngokwamasiko.

I-WHR iqhathaniswa nobukhulu bomzimba?

Inkinga yezibalo esabalele yokusatshalaliswa kokuguquguqukayo nakho kuyinkinga (bona iposi lami likaJulayi 12, 2013 Ugibe Lukanogolantethe Nezingane ). Esinye isici esingahle siphendule izinhlangano eziphakathi kwezilinganiso eziphansi ze-WHR nezikhangayo. Isibonelo, kuphakanyisiwe ukuthi umthelela wangempela wokushayela yinkomba yomzimba (BMI).

Ku-2011, u-Ian Holliday nozakwabo basebenzise ukuhlaziywa okuningana kwemizimba yabesifazane ukwakha izithombe ezenziwe ngamehlo ezi-3 ezihlukaniswe ngokwe-BMI noma i-WHR. Izilinganiso zokuheha ngabo bobabili abesilisa nabesifazane kubikwa ukuthi zihambisana nokwehluka kwe-BMI kepha hhayi ku-WHR. Ukuskena kobuchopho okurekhodwe nge-MRI esebenzayo ngesikhathi sokuhlolwa kuveze ukuthi ukuguqula umsebenzi olinganiselwe we-BMI ezingxenyeni zohlelo lomvuzo wobuchopho. Kuphethwe ukuthi ubukhulu bomzimba, hhayi ukuma komzimba, empeleni kuheha ukuheha.

Kodwa-ke ngo-2010, ucwaningo olwenziwe ngamasiko ahlukene olwabikwa nguDevendra Singh, uBarnaby Dixson, u-Alan Dixson nabanye lwaba nemiphumela ehlukile. Laba babhali bavumele imiphumela engaba khona ye-BMI ngokusebenzisa izithombe zokuhlola zabesifazane abebehlinzwe ngezimonyo ze-micrograft ukuze banciphise okhalweni baphinde babumbe izinqe, bashintshe i-WHR ngqo. Kuwo wonke amasiko ahlolwe, abesilisa bahlulela abesifazane abane-WHR ephansi njengabakhanga kakhulu ngaphandle kokukhuphuka noma ukwehla kwe-BMI.

Ezinye izizathu zokuqapha

Ukuchazwa kwanoma iyiphi inkomba elula yokuheha kwabesifazane njenge-WHR kuyangabazeka. Izethulo ze-Rudimentary 2D zomzimba wesifazane ojwayele ukusetshenziswa ekuhlolweni zenziwe zaba lula kakhulu uma kuqhathaniswa neqiniso le-3D eliyinkimbinkimbi. Ngaphezu kwalokho, izinhlaka zomzimba zikhonjiswa ikakhulu ekubukeni kwangaphambilini. Kuncane okwaziwayo ngezimpendulo zamadoda ekubukeni emuva noma eceleni, ingasaphathwa eyeqiniso le-3D jikelele.

Ephepheni lango-2009, uJames Rilling nozakwabo basebenzise inqubo ebanzi yokuhlola efaka amavidiyo e-3D ne-2D isadonsa ngamamodeli wangempela abesifazane ajikeleza emkhathini. Ukuhlaziywa kukhombise ukuthi ukujula kwesisu kanye nobubanzi besinqe kwakuyizimbangi eziqine kakhulu zokuheha, okwedlula i-WHR ne-BMI.

Umuntu oyedwa ozobekwa phambili ekusayineni ngokungaphambili - isihluthu sezinwele zasesizalweni esikhula lapho uthomba futhi esikhombisa ukuguqukela ekubeni ngowesifazane - akuvamile ukubhekwa. Okuhlukile okuphawuleka ngocwaningo lwakamuva olwenziwe nguChristopher Burris no-Armand Munteanu labafundi besilisa abenza iziqu zokuqala, phakathi kokunye, okuhloliwe izimpendulo ekushintsheni okuphawulwe ezinweleni zezinsikazi zabesifazane. Ngokumangazayo, ukungabikho ngokuphelele kwezinwele zasesidlangalaleni kukalwe njengokuvusa inkanuko ngokuphelele. Lokhu kwahunyushwa nge-hypothesis ehlanganisiwe exhumanisa izinwele ezandayo zabesifazane kubantu besifazane kumazinga aphezulu we-testosterone nokungabi nenzalo nokubeka izilinganiso eziphakeme emadodeni athambekele kahle ekuzaleni kwabesifazane. Kepha iphuzu elibucayi, eliphazamisayo lidluliselwe ngaphandle kokubalulwa: Kunoma ikuphi ukwenzeka kokuziphendukela kwemvelo, ukungabikho ngokuphelele kwezinwele zasesidlangalaleni kufanele kukhombise ukungabi nenzalo ngenxa yokungavuthwa. Kungenzeka kanjani ukuthi umuntu akuchaze ngokuthandwa kwe-bikini ye-wax waxing ngamagama wokuziphendukela kwemvelo?

Akunandaba nemininingwane, kufanele sixwaye noma iyiphi incazelo yokuziphendukela kwemvelo eyehlisa ukuxhumana kwabantu okuyinkimbinkimbi ekuziphatheni okulula kokuphendula kwama-sticklebacks.

Izinkomba

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