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WonderVision biology fact1,764 of 1,961

Reindeer eyes transmit and respond to ultraviolet wavelengths, a capacity that can sharpen contrast for food, predators and urine marks in an Arctic landscape.

Ultraviolet winter

NatureBiologyEvolution

Why it matters

The idea in context

Snow reflects ultraviolet light strongly, while lichen, fur and urine absorb or scatter it differently. To a reindeer, the Arctic is therefore not the nearly blank white field humans imagine. Its eye opens a hidden layer of contrast—an elegant example of perception being tuned not to the world in general, but to one difficult world in particular.

Türkçe

Aynı kart, başka bir dilde.

Ren geyiğinin gözleri morötesi dalga boylarını geçirip algılar; bu yeti Arktik peyzajında yiyecek, avcı ve idrar izlerinin kontrastını artırabilir.
Morötesi kış

Kar morötesi ışığı güçlü biçimde yansıtır; liken, kürk ve idrar ise onu farklı şekilde soğurur ya da saçar. Bu nedenle Arktik, ren geyiğine insanın hayal ettiği neredeyse dümdüz beyaz alan gibi görünmez. Gözü, saklı bir kontrast katmanını açar: algının genel bir dünyaya değil, özellikle zor bir dünyaya ayarlandığının zarif bir örneği.

Source trail

Read beyond the card.

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