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A man developed a condition known as hairy tongue, which can manifest itself in different colors depending on the bits of food, bacteria and dead skin cells that get trapped in the "hairs."

A series of laser flashes recently lit up the night sky above Mauna Kea in Hawaii. Experts say the lasers were emitted by a NASA spacecraft.

Products of chlorophyll breakdown make ripening bananas glow blue under black lights.

The planet has endured far more dramatic climate change in the past fueled by other forms of life. But rarely if ever has the change been so rapid.

Hordes of mountain pine beetles are decimating British Columbian forests.

Tree growth in temperate forests is driven by availability of water and not by temperature as previously thought.