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Planet Earth

That Word You Heard: Crepuscular

These animals are active from dusk 'til dawn.

By Lacy SchleyJune 12, 2019 5:00 AM
Crepuscular - Chad Edwards
(Credit: Chad Edwards)


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For most of us, when the sun’s up, we’re up. Other critters are nocturnal, operating mainly at night. But not everything falls into those two camps. Many creatures are crepuscular — most active at dusk and dawn — including some species of butterflies, bees, deer, rabbits, even house cats. The trait can allow these animals to avoid extreme temperatures, predators and competition with others over resources. Meteorologists also use the term to describe some types of light rays from the sun, such as the ones that pierce through clouds like spotlights.

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