• Catoblepas
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      5 days ago

      It is if you live in a part of the world that is dark for months at a time during the winter, like reindeer do.

    • Suru@mander.xyz
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      5 days ago

      Most reindeer live North of the Arctic Circle, where the sun does not rise above the horizon in winter months. I suspect most summer days are brighter than the few hours of twilight the reideer get in December.

    • TachyonTele@lemm.ee
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      5 days ago

      The pupil dilates, combined with more uv light seasonally, changes the structure of the iris and thus it’s color. (It reflects differently)