the.com/tapetum
the mirror behind the eye that gives night animals a second shot at every photon.
means a reflective layer behind the retina in many animals that bounces unabsorbed light back through the photoreceptors, boosting night vision at the cost of sharpness.
from from latin tapete, meaning carpet or tapestry, because early anatomists saw a shimmering layered sheet behind the retina and named it for its woven, textile-like look.
eyeshine causeheadlights hitting the tapetum make eyes glow in photos
color variestapetum tint shifts eyeshine from green to gold to red
humans lack itprimates traded the tapetum for sharper daytime color vision
crystal compositionmade of zinc or riboflavin crystals in different species
for instance
cat eyeshine — cats see roughly six times better in dim light than humans
deer headlight glow — why deer freeze, momentarily blinded by reflected glare at night
shark tapetum lucidum — lets sharks hunt effectively at ocean depths below 200 meters
dog night vision — dogs rely on it for low-light tracking since domestication