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就这样挂在小溪上方的树叶上,几天后树蛙卵终于变成了蝌蚪。鳞茎卵黄囊为其提供营养。受精卵一天天长大,卵胶膜破裂——可能是蝌蚪体内发生了某种化学变化——于是,一只接着一只,它们滑入下方的水中,开始自己的生命周期。
Within days of being deposited on a leaf overhanging a stream, tree frog eggs grow into recognizable tadpoles. Bulbous yolk sacs provide nourishment. As the wrigglers develop, the gelatinous outer membrane decomposes, perhaps triggered by a chemical change in the tadpoles. One by one, they slide off to a life of their own in the water.
(Photo shot on assignment for "Nature's Living, Jumping Jewels," July 1973, National Geographic magazine)
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