Dioecy

Dioecy (Greek: "two households"; adjective form: dioecious) is a characteristic of a species, meaning that it has distinct male and female individual organisms or colonies, meaning that a colony contains only either male or female individuals. Dioecious reproduction is biparental reproduction.

In zoology

In zoology, dioecious species may be opposed to hermaphroditic species, meaning that an individual is of only one sex, in which case the synonym gonochory is more often used. Dioecy may also describe colonies, such as the colonies of Siphonophorae, which may be either dioecious within a species or monoecious. Dioecious colonies contain members of only one sex, whereas monoecious colonies contain members of both sexes.

Most animal species are dioecious (gonochoric).

In botany

Dioecious species have the male and female reproductive structures on separate plants. The meaning of male and female in the context of plants is different from that used in animal groups and the usage is not strictly correct. This issue is discussed below in the Alternation of generations section. About 6 percent of angiosperm species are entirely dioecious and about 7% of angiosperm genera contain some dioecious species. Examples of dioecious plant species include ginkgos, willows, cannabis and African teak. More examples of dioecious plants can be found in the Wikipedia category, Dioecious plants.

Plant reproductive morphology

Plant reproductive morphology is concerned with the physical form and structure (the morphology) of those parts of plants directly or indirectly concerned with sexual reproduction.

Among all living organisms, flowers, which are the reproductive structures of angiosperms, are the most varied physically and show a correspondingly great diversity in methods of reproduction. Plants that are not flowering plants (green algae, mosses, liverworts, hornworts, ferns and gymnosperms such as conifers) also have complex interplays between morphological adaptation and environmental factors in their sexual reproduction. The breeding system, or how the sperm from one plant fertilizes the ovum of another, depends on the reproductive morphology, and is the single most important determinant of the genetic structure of nonclonal plant populations. Christian Konrad Sprengel (1793) studied the reproduction of flowering plants and for the first time it was understood that the pollination process involved both biotic and abiotic interactions. Charles Darwin's theories of natural selection utilized this work to build his theory of evolution, which includes analysis of the coevolution of flowers and their insect pollinators.