Like most species of birds, male and female ostriches have differing color patterns. When most people think of an ostrich, they picture the distinctive black and white coloring of males. Female ostriches' feathers have a far more muted color, typically in shades of brown or taupe. In addition to a more muted color pattern, female ostriches are generally smaller than the males of their flock. These differences in color and size are an example of something called sexual dimorphism, where the two sexes of a species have differing physical presentations. Several theories have been proposed concerning sexual dimorphism in birds. One idea is that females have developed muted color patterns as an adaptation which allows them to blend into their natural environment, making them less likely targets for attack. The survival of females is key for the survival of any young she may have, so being able to hide would certainly offer an advantage. On the other hand, some people feel that the brighter color patterns of male birds is the stronger adaptation. Males often display their plumage to attract a mate.