The Real Reason Cacti are Prickly

A cactus is the ultimate "do not touch me" plant. You might think that those prickly spines are a natural defense against the plant being eaten by wild animals, but there's much more to it than that. The cactus garden in my kitchen displays a wide variety of those spines, from some that are barely discernible to one plant I have to wear leather gloves to work with. Cacti have an astonishing number of weird features that help them survive in inhospitable places, from wax skin to temporary roots. (via Damn Interesting)