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WonderAnimal physics fact1,790 of 1,961

Archerfish knock insects from vegetation with jets of water and compensate for optical refraction when aiming through the air-water boundary.

A ballistics lesson below the surface

BiologyScienceNature

Why it matters

The idea in context

Viewed from underwater, an insect's apparent position is displaced because light bends at the surface. The archerfish still aligns a forceful jet, adjusting for target height and learning unfamiliar distortions through experience. Its shot is more than a trick of the mouth: perception, fluid mechanics and prediction meet in a fraction of a second.

Türkçe

Aynı kart, başka bir dilde.

Okçu balıkları su jetleriyle bitkilerdeki böcekleri düşürür ve hava-su sınırından nişan alırken ışığın kırılmasını telafi eder.
Yüzey altındaki balistik dersi

Suyun altından bakıldığında ışık yüzeyde kırıldığı için böceğin görünen yeri kayar. Okçu balığı yine de güçlü jeti hizalar, hedef yüksekliğine göre ayar yapar ve deneyimle alışılmadık bozulmaları öğrenir. Atış yalnızca ağzın numarası değildir: algı, akışkanlar mekaniği ve öngörü saniyenin küçük bir parçasında buluşur.

Source trail

Read beyond the card.

Background reading: ArcherfishAttribution and context are revised when stronger evidence appears. Corrections are welcome through the editorial page.
Open in the iPhone appEditorial method

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