Evolutionary adaptation is the process by which a type of organism becomes better at surviving in its environment. Roses, (Rosa spp.) a common cultivated flower in United States Department of Agriculture plant hardiness zones 4 to 8, have a variety of adaptations to encourage their survival and reproduction. These include defensive and reproduction adaptations, as well as some changes that allow the rose to survive harsh conditions.
Thorns are the most obvious adaptation of roses. The short spines on these plants help discourage plant-eating animals from consuming the rose bush. Animals that do attempt to eat roses are pricked, but not seriously harmed. These structures are outgrowths of the outer layer of tissue in the rose stem, and tend to be sickle or hook shaped. Rose thorns do not grow on the leaves, and will not protect them, however.
Roses' white, red and pink petals work well to attract pollinating insects, which see primarily in this color range. These flowers also produce sweet smells, which attract bees and other insects. Roses are primarily pollinated by bees, including green flower bees, honey bees and bumble bees. Since these bees are not specialized pollinators, roses produce large amounts of pollen to increase the chances of reproduction.
Rose bushes are capable of surviving significant defoliation; they can lose most of their leaves and still survive. This means that roses that have had their leaves stripped and still continue to grow without problems. The many wild forms of the rose are capable of thriving at varied elevations and in many different environments beyond the scope of its cultivated counterpart's plant hardiness range, thriving in full sunlight to moderate shade.
This plant produces extensive rhizomes, or root-like structures, from which it can regrow after the above-ground growth has been destroyed. Roses tolerate fire well, and often survive to sprout again after being burned. They may also grow back after having been down entirely. This can make them a problem for gardeners, who must uproot the entire plant, but enables the rose bush to survive harsh conditions and significant damage.