Гомосексуальность у нечеловекообразных приматов

 

Если гомосексуальность имеет биологическую основу, а не просто феномен, рожденный воспитанием или средой, должны существовать свидетельства гомосексуального поведения у наших близких сородичей – нечеловеческих приматов. Однако свидетельства эти встречаются довольно редко.

Правда, что самцы приматов часто взбираются на других самцов сзади[79]. Однако это поведение, по‑видимому, мало связано с достижением оргазма или какого‑либо сексуального удовольствия; пенетрация в естественном состоянии случается редко, если случается вообще. Это просто статусный прием того, кто сверху. Тот, кто забирается наверх, утверждает свое доминирование, а тот, на кого взбираются, подчиняется и принимает свой более низкий статус. Это взаимодействие между самцами часто наблюдается у видов, у которых мужская иерархия имеет огромное значение для социальной системы, таких как макаки и бабуины. Самцы бабуинов также известны тем, что хватают друг друга за яички в ходе социального взаимодействия. Но это является знаком мужского альянса, а не секса. Самцы бабуинов делают это в качестве приветствия или, чтобы выразить доверие друг другу, или успокоить в напряженные моменты[80]. У одного вида игра между молодняком принимает решительно гомосексуальное направление: молодые самцы бонобо сосут пенисы друг друга, от чего, должно быть, получают удовольствие, но это выглядит как способ развлечения, а не истинная сексуальность[81].

Гомосексуальность среди самок нечеловеческих приматов четко задокументирована у нескольких видов – резусы, японские макаки, медвежьи макаки, гульманы и бонобо[82]. Механизм гомосексуальности самок отличается у разных видов[83]. У самок японских макак, например, в период эструса присутствует сильная мотивация взбираться на других самок и тереться клитором об их спину. Кроме того, они формируют с другими самками половые связи, длящиеся несколько дней. Они делают это, как предполагает приматолог Линда Волфе, потому что в группе часто недостаточно самцов для вступления в брачные и половые отношения, таким образом, под влиянием идущего изнутри полового влечения они вступают в такие отношения с самками[84]. Гульманы делают то же самое – самки взбираются друг на друга только в период эструса и трутся лобком о спины других самок[85]. С другой стороны, бонобо используют гомосексуальность так же, как они используют гетеросексуальность – по социальным причинам. Самка бонобо, входя в новую группу, обычно упрощает себе этот процесс, если она подходит к каждой самке в группе и демонстрирует свои набухания для того, чтобы потереться друг о друга гениталиями[86]. Она и ее партнерша похлопывают друг друга и качают своими набуханиями взад и вперед. Гомосексуальность в этом случае – пропуск в жизнь группы, а не сексуальная интрижка.

Хотя есть свидетельства случайного поверхностного интереса в гомосексуальности у нескольких видов нечеловеческих приматов, особенно между некоторыми самками обезьян, данные не подтверждают с достаточной силой гомосексуальность на уровне отряда. Другие приматы могут использовать то, что мы, люди, называем гомосексуальным поведением, для снижения социального напряжения, чтобы вступить в социальный контакт или чтобы получить что‑то от партнера. Но они никогда не являются исключительно гомосексуальными или регулярно гомосексуальными, как это происходит у некоторых людей. Только когда мы наблюдаем далеко идущее разнообразное сексуальное поведение, как у бонобо, гомосексуальность проявляется в качестве регулярной черты. Таким образом, корни гомосексуальности могут быть отмечены у наших сородичей‑приматов, но, по всей видимости, мы являемся единственными приматами, где некоторые члены вида ведут исключительно гомосексуальный стиль жизни.

 

Эволюция гомосексуальности

 

Если мы примем то, что определенный процент мужчин и женщин в каждом человеческом обществе называет себя гомосексуалами, и то, что гомосексуальные акты всегда имели место, поскольку человеческая история фиксировала такую информацию, возникнет очевидный вопрос: «Почему?» Естественно, эволюционные биологи, теоретики, посвятившие себя пониманию истинных причин человеческого поведения, должны иметь ответ на кажущуюся универсальной среди нашего вида гомосексуальность.

Оказывается, этот вопрос ставит их в тупик. Гетеросексуальное поведение со всеми его наслоениями любви и вожделения можно легко объяснить в качестве способа природы заставить нас, представителей вида, размножающегося половым путем, объединяться и передавать гены. Однако гомосексуальность представляет для биологии особую дилемму. Если есть поведение, напрямую связанное с размножением, но по определению созданное не для передачи генов, то как же оно могло развиться в качестве стратегии половых отношений?

С одной стороны, гомосексуальность можно рассматривать в качестве эволюционного отклонения. Не все человеческое поведение является приспособлением, возможно, гомосексуальность – это одна из схем, наблюдающаяся время от времени и не передаваемая по наследству. Биолог Эдвард О. Уилсон имеет другую точку зрения. Он считает гомосексуальность поведением, управляемым генами и развившимся из‑за своих преимуществ[87]. Его логика состоит в следующем: гомосексуальность является универсальной человеческой чертой, а потому имеющей генетическую основу. Хотя многие гомосексуалы не передают гены напрямую, у них общие гены с их родственниками. Любая помощь, которую гомосексуал оказывает своей семье, помогает передавать эти рецессивные, но крайне альтруистические гены. По мнению Уилсона, гомосексуалы являются носителями очень редкой у нашего вида склонности к альтруизму, и гены гомосексуальности передавались вместе с этими особенными и важными генами альтруизма. Он представляет это себе так, что на ранних этапах наши предки жили в небольших родственных группах, эти альтруистические гомосексуалы были неотъемлемой частью здоровья и благополучия более крупных родственных групп. Их альтруизм и их гомосексуальность существуют сегодня, потому что наши предки нуждались в помощи, которую гомосексуалы предоставляли группе.

Это интересный и единственный эволюционный из известных мне подходов. Однако в нем есть большие пробелы. Во‑первых, не существует доказательств того, что гомосексуалы более или менее альтруистичны, чем гетеросексуалы. Возможно, дядя‑гомосексуал поведет племянников развлекаться в торговый центр, но то же сделает и их гетеросексуальная тетя. В долгосрочной перспективе не существует абсолютно никаких доказательств того, что гомосексуалы среди наших предков имели влияние на успех взращивания чужих детей. Во‑вторых, у многих гомосексуалов есть дети. У мужчин‑геев часто есть семьи, и женщины‑лесбиянки часто заводят детей. Мысль о том, что гомосексуальность была выбрана естественным отбором, потому что гомосексуалы посвящали свою жизнь заботе о чужих генах, сомнительна. Это интересная возможность, но она безосновательна.

Возможно, мы не можем придумать хорошего эволюционного объяснения гомосексуальности, потому что его не существует. Если гомосексуальность является вариантом человеческого социального континуума, нам не нужно искать ответ на вопрос «почему?» относительно ее появления. Вероятно, вся человеческая сексуальность в каком‑то смысле является генетической, и вероятно, существуют гены, отвечающие за склонность к определенному месту в этом континууме. Но эти гены не подразделяются удобно, как и мы сами, на категории гомосексуальности, гетеросексуальности, бисексуальности. Поиск биологической, эволюционной или психологической причины гомосексуальности, по моему мнению, безрезультатен. Ученые и теоретики заняты поиском корней гомосексуальности, тогда как, возможно, они могли бы потратить время с большей пользой в поисках биологической основы сексуальности в целом. Мы знаем о существовании гомосексуальности, и мы знаем, что большая часть людей думали или реагировали на гомосексуальные импульсы, а небольшое число приговорено к представителям своего пола. Что из того? Рассмотрение гомосексуальности в качестве болезни и поиск ее причин для меня лишены смысла. Вместо этого я бы расширила горизонты наших ученых, чтобы объяснить, почему человеческая сексуальность является континуумом, а не аккуратными упаковками того или иного. Если исследования биологии гомосексуальности помогут нам понять биологию сексуальности в целом, то я заинтересована в этих возможностях.

 

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