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WonderGene-culture coevolution fact1,719 of 1,961

Lactase persistence, the adult ability to digest milk sugar, evolved in some dairying populations as culture created a new selection pressure.

Gene-culture coevolution

EvolutionBiologyFoodCultureScience

Why it matters

The idea in context

Most mammals, including many humans, reduce lactase after childhood. But when some communities began herding milk-producing animals, fresh milk became an adult food with real survival value. Genetic variants that kept lactase switched on spread in several places, not as a simple universal story but as a beautiful case of gene-culture coevolution. A custom changed the environment; the body answered.

Türkçe

Aynı kart, başka bir dilde.

Yetişkinlikte süt şekerini sindirme yeteneği olan laktaz kalıcılığı, bazı sütçül topluluklarda kültürün yeni bir seçilim baskısı yaratmasıyla evrildi.
Gen-kültür birlikte evrimi

Birçok insan dahil çoğu memeli, çocukluktan sonra laktaz üretimini azaltır. Fakat bazı topluluklar süt veren hayvanları gütmeye başlayınca taze süt, yetişkinler için gerçek yaşamsal değeri olan bir yiyeceğe dönüştü. Laktazı açık tutan genetik varyantlar birkaç bölgede yayıldı; bu basit ve evrensel bir hikaye değil, gen-kültür birlikte evriminin güzel bir örneğidir. Bir gelenek çevreyi değiştirdi; beden cevap verdi.

Source trail

Read beyond the card.

Background reading: Lactase persistenceAttribution and context are revised when stronger evidence appears. Corrections are welcome through the editorial page.
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