Understory

... see now are simply a carry over charateristic of those cells. This would seem to make sense since many plant leaves with red pigments are found as understory plants, however it's not always the case as many are found growing in full sun.

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... the giant panda) resembles a raccoon in size and appearance. The red panda weighs 3 - 6 kg (7 - 13 lb). It lives in mountain forests with a bamboo understory, at altitudes generally between 1500 and 4800 m (5000 - 15,700'). Red pandas almost exclusively eat bamboo. They are good tree climbers and ...

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