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WonderAnimal migration fact1,711 of 1,961

European eels hatch in the Sargasso Sea, drift toward Europe as transparent larvae, then return across the Atlantic as adults to spawn.

Atlantic migration to the Sargasso Sea

MigrationOceanBiologyEvolution

Why it matters

The idea in context

For centuries, eel reproduction felt like a scientific riddle because the adults left rivers and vanished into the Atlantic. The life cycle is now clearer, though still wonderfully strange: sea-born larvae ride currents toward Europe, become glass eels at the coast, mature in rivers and wetlands, then turn silver and leave again. A single animal can make freshwater feel temporary and the open ocean feel like home.

Türkçe

Aynı kart, başka bir dilde.

Avrupa yılan balıkları Sargasso Denizi'nde yumurtadan çıkar, saydam larvalar olarak Avrupa'ya doğru sürüklenir, yetişkin olduklarında yumurtlamak için Atlantik'i yeniden aşar.
Sargasso Denizi'ne Atlantik göçü

Yüzyıllar boyunca yılan balıklarının üremesi bilimsel bir bilmece gibiydi; çünkü yetişkinler nehirlerden ayrılıp Atlantik'te kayboluyordu. Yaşam döngüsü artık daha anlaşılır, ama hâlâ harika derecede tuhaf: denizde doğan larvalar akıntılarla Avrupa'ya taşınır, kıyıda cam yılan balığına dönüşür, nehir ve sulak alanlarda olgunlaşır, sonra gümüş rengine bürünüp yeniden yola çıkar. Tek bir hayvan, tatlı suyu geçici; açık okyanusu ise yuva gibi gösterebilir.

Source trail

Read beyond the card.

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