The orchid family is one of the largest families of flowering plants. There are twice as many species of orchids as species of birds. There are four times as many species of orchids as species of mammals. Charles Darwin wrote a book about orchids in 1862. The book studied the way in which orchids evolved to attract birds and insects. It is suggested that for every different type of bird or insect, there was an orchid that matched in appearance. This in-depth study on orchids helped Darwin develop his ideas on evolution. Orchids can survive almost anywhere—even underground. The only place they cannot survive is in glacial regions, like Antarctica. They grow best in tropical regions that are hot and humid. Some scientists believe that orchids have been around since the time of the dinosaurs.
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