A vestigial structure is a structure that is present in an organism, but it has no function. A very common example is the human appendix. Pictured is a dandelion. Dandelions have sexual organs, but they reproduce exclusively through asexual reproduction. This means that even though dandelions have sex organs such as the stamen, pistil, pollen, etc. they have no function. Dandelions produce seeds by an asexual process called apomixis, and all offspring are genetically identical clones of the parent. The sex organs of the dandelion are neither used for sexual reproduction nor for any other purpose.