Unformatted text preview: Pollination . Flowers and their pollinators coevolved; that is, two or more species act as selective forces on one another and each undergoes evolutionary change. Early flowers probably were wind pollinated, but the selective advantages of cross-fertilization by animal pollinators must have been a powerful selective evolutionary force from the very beginning. Specializations to ensure cross-fertilization and attract pollinators include: colors in wavelengths visible to the pollinators; nectaries placed so that access requires passage across pollen sacs; odors; structural changes such as long corolla tubes and spurs filled with nectar. Dispersal . Concomitant with the changes to insure fertilization are those that insure dispersal of the products of fertilization, such as the seeds and fruits. Fruits can be dry or fleshy, remain closed or split open at maturity, have hooks or spines that attach to fur or feathers. Seeds can have hard split open at maturity, have hooks or spines that attach to fur or feathers....
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