Cacti are adapted to live in very dry environments, including the driest places on Earth. Because of this, cacti show many adaptations to conserve water almost all cacti are succulents, with thickened, fleshy parts adapted to store water. Most species of cacti have lost true leaves, retaining only spines, which are highly modified leaves. As well as defending against herbivores, spines help prevent water loss by reducing air flow close to the cactus and providing some shade. In the absence of true leaves, cacti's enlarged stems carry out photosynthesis.

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拍攝者： Galumphinggalah