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The Prickly Pear Cactus
Prickly pear cactus are found in all of the deserts of the American Southwest. Most prickly pears have large spines, actually modified leaves, on their stems and vary in height from less than a foot to 6 or 7 feet.

 

The Desert Food Chain
A food chain constitutes a complex network of organisms, from plants to animals, through which energy, derived from the sun, flows in the form of organic matter and dissipates in the form of waste heat.