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WonderCave evolution fact1,803 of 1,961

Separate cave populations of the Mexican tetra repeatedly evolved reduced eyes and pigmentation, providing natural replicates of adaptation to permanent darkness.

Evolution's experiment in darkness

EvolutionBiologyScience

Why it matters

The idea in context

Surface and cave forms belong to the same species, and more than thirty cave populations offer repeated versions of a similar challenge. Eyes and pigment diminish while smell, taste, vibration sensing and metabolism change, but the genetic routes can differ between caves. Convergence produces a familiar destination without requiring one prescribed road.

Türkçe

Aynı kart, başka bir dilde.

Meksika tetrasının ayrı mağara popülasyonları göz ve pigmenti tekrar tekrar azalttı; kalıcı karanlığa uyumun doğal tekrarlarını sundu.
Evrimin karanlık deneyi

Yüzey ve mağara biçimleri aynı türe aittir; otuzdan fazla mağara popülasyonu benzer bir sınavın yinelenen sürümlerini sunar. Göz ve pigment azalırken koku, tat, titreşim algısı ve metabolizma değişir; ancak genetik yollar mağaradan mağaraya farklı olabilir. Yakınsaklık, tek bir zorunlu yol olmadan tanıdık bir varış üretir.

Source trail

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