Do Plants Have Sex?

plant, plants, sex, sexual, reproduction, stamen, pollen, stamen, flower, flowers, ovule, egg, seed, seeds — Flowers reproduce when the pollen is carried by an unknowing participant to another flower's stigma.

Minus bad pickup lines, one-night stands, and other social complexities, plants actually do have sex. When people pluck the sweet-smelling blooms of a plant, they’re actually dismembering the reproductive organs of plants! The “male” portion of the flower is the pollen-loaded stamen, while the egg-holding pistil is the “female” part. Most plants sprout bisexual flowers (which have both male and female parts), but plants like squash grow separate male and female flowers — still others have both bisexual and single-sex flowers. And, as evolutionary biologists have recently discovered, plants with male and bisexual flowers produce more seeds. Why this is true is a new scientific mystery, but it probably has something to do with male flowers hoarding less of a plant’s energy (making more of it available to crank out seeds). So how do flowering plants do it? Using nature as a matchmaker, wind, animals, or water carry pollen to a sticky female stigma. The grains then germinate and grow downward, creeping slowly towards the ovaries. Eventually, the pollen grains bump into some eggs: Ta-da, seeds are born (yes, eating an apple or other fruit means eating an unborn life form!). But flowers aren’t the only way plants know how to get it on . Ginkgo trees have separate male and female plants altogether. Male trees produce spores which hatch into sperm, swimming to an egg inside a female ovule. Still other plants — such as duckweed — abstain from sex altogether. These curious plants produce leaf-like clones that break off and grow into adult plants.

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Dave Mosher, currently the online director at Popular Science, writes about everything in the science and technology realm, including NASA's robotic spaceflight programs and wacky physics mysteries. He has written for several news outlets in addition to Live Science and Space.com, including: Wired.com, National Geographic News, Scientific American, Simons Foundation and Discover Magazine. When not crafting science-y sentences, Dave dabbles in photography, bikes New York City streets, wrestles with his dog and runs science experiments with his nieces and nephews.