Hotunan Biyanci / Hotunan Getty

A yawancin dabbobi, mace sun fi maza girma, amma a yawancin dabbobi masu shayarwa akasin gaskiya ne. Marcelo Cassini, mai bincike a Cibiyar nazarin halittu da Magungunan gwaji a Argentina, ya buga takarda a cikin jaridar Mammal Review, wanda ke ba ku damar buɗe rufin asirin akan wannan batun.

A yawancin halittu masu rai, mace sun fi maza girma. A zahiri, a yawancin jinsunan dabbobi masu shayarwa, dimorphism dangane da girman mutum yana da son kai ga maza. Don yin bayanin wannan sabon abu, masana kimiyya sun ba da ra'ayi da yawa. Zuwa yau, bayanin da aka yarda dashi gaba daya shine cewa bambancin jima'i a cikin dabbobi masu shayarwa ya samo asali sakamakon zabin jima'i tsakanin maza.

Mai binciken ya gudanar da bincike kan al'ummomin nau'ikan halittar magabantan 50 da kuma amfani da mafi karancin tsarin murabba'i wanda yanayin dimorphism ya kasance mai dogaro da juna, kuma alamomin da aka bayyana a sama sun kasance masu zaman kansu. A sakamakon haka, masanin kimiyyar ya nuna cewa matakin dimorphism na jima'i yana da alaƙa kai tsaye da alamomi guda huɗu - rabo na maza, tsarin matsi, gasa da kuma yawan ayyukan gungun.

A cikin aikinsa, Cassini ya ƙarasa da cewa a cikin manyan rukuni, maza za su rasa ikon halayen jima'i na wasu membobin ƙungiyar ko damar ba da damar haihuwa. Don haka, don adana kwayoyin halittarsu, dole ne mazan su zama manya don samun damar yin amfani da wasu mutane kuma su yi hulɗa tare da mata da yawa. A sakamakon haka, kwayoyin halittar maza manya manya ke yadawa daga tsara zuwa tsara. Don haka, bisa ga binciken, rawar da ke cikin dimorphism ana yinsa ne ta hanyar zaɓin yanayi, kuma ba jima'i kawai ba.

Namiji maza sun koya don sanin kafircin “haliman” nasu. Suna yanke shawara dangane da halayen mace kuma sun sami damar "ladabtar" dasu saboda zuwa "hagu".

Groupungiyar ƙwararrun masan kimiyya na Biritaniya da na Jamus sun gudanar da wani bincike game da yadda maza zazzagewa maza suke amsa rashin aminci ga mata, kuma sun ƙarasa da cewa tsuntsaye suna sane da wannan halayyar abokin tarayya. A cikin ramuwar gayya, maza sun sa ƙarancin ƙoƙari wajen ciyar da 'ya'yansu, wanda hakan na iya ƙarfafa mata su kasance da aminci. An buga labarin mai dacewa a cikin Masanin dabi'ar Amurkawa.

A cikin dabbobin daji, da dama nau'in za su iya lura da tsayayyun auren mace ɗaya (karnukan karnukan daji), ko buɗe auren mata fiye da ɗaya (karnuka ɓatattu), amma har da wasu zaɓuɓɓukan matsakaici. Talakawa maɗaukaki suna da irin wannan yanayin. Kamar yadda a yawancin al'adu a cikin mutane, auren mace ɗaya shine abu ɗaya tsakanin waɗannan tsuntsayen, amma wasu daga cikin ɓarna sun zama masu iya zina, wani lokacin ma. A lokaci guda, masana ilimin dabbobi sun lura da cewa maza masu rayuwa tare da mace marasa aminci suna isar da ƙarancin abinci ga kajin a gida. Koyaya, ba a san mecece dalilin hakan ba: irin martani ga "cin amana" da abokin tarayya, ko kuma gaskiyar cewa irin waɗannan mata an haɗa su tare da namiji mara hankali.

A sakamakon haka, ya juya cewa lalacewar mazan ba shi yiwuwa don zama bayani don raguwar ayyukansu a cikin hakar abinci idan akwai rashin aminci ga abokin tarayya. Don haka, yayin da namiji, saboda wasu dalilai, ya sauya daga abokin amintaccen zuwa “wanda ba daidai ba”, kokarin sa na isar da abinci a gidan ya ragu, dukda cewa sartalin da kansa ya kasance a zahiri. Gaskiya ne, lokacin da amintattun marasa aminci suka kirkira tsakanin maza da maza da suka kawo ƙarin ganima, sun fara canzawa “matansu” ƙasa kaɗan, kodayake basu daina irin wannan halayen ba kwata-kwata. Don haka, mizanin ciyar da ƙasa gaba ɗaya an ƙaddara ta halayen sahabbai, bawai ta hanyar aiki na ƙuruciya ba ko kuma lalaci.

Don fayyace ainihin yadda sparrow yake samun labarin yaudara, masana kimiyya sun gudanar da gwaji. Sauran jefa ƙwai mutane an jefa su a cikin mazaunan amintattun kuma suna duba don gani idan ƙoƙarin namiji ya samu abinci don broods sai ya canza. Kamar yadda ya juya, wannan bai faru ba. Don haka, ya bayyana a fili cewa kafirci yana tabbatarwa ne ta hanyar mazajen mata ba ta halayen mutum ne na qwai (misali, warinsu), amma ta halayen macen amana. Masana ilimin halittu sunyi imani da cewa muddin maniyyi zai iya jagorar ta har tsawon lokacin iṣe ya kasance a waje da mazaunin su kafin lokacin kwanciya.

A cewar masu binciken, tsarin da aka lura da su "karancin samar da martani ne ga cin amanar kasa" na iya yin bayanin wasu dalilai na zabi wasu matan. Lokacin da mace tayi aiki da akasi ga wasu ka'idodi na jinsin su, suna fuskantar barazanar rashin abinci mai inganci ga kajin. Don haka, a nasu bangare, biyayya na iya zama dabarar juyin halitta.

A lokaci guda, masanin ilmin halitta Alexander Markov, yayin da yake Magana game da batun haihuwar maza masu hadari, ya lura cewa mata marasa aminci sun gwammace su “a gefe” tare da mazajen da ke da matukar alamar “masculinity” - baƙar fata a tsakiyar kirji. Irin waɗannan mutane suna iya barin strongera strongeran da ke da ƙarfi da koshin lafiya, wanda har zuwa wani lokaci za su rama rashin ƙarancin abinci mai gina jiki daga “mahaifin mai haihuwar.”