Yes, birds, bees, humans, and other higher forms of life, all do it – sexual intercourse, that is. But guess what? Plants are also doing it! Yes, you read that right. The beautiful flowers that delight our eyes and noses, the fruits and vegetables that delight out palates and sustain our bodies, and the majestic trees that provide us with shade and oxygen are all having sex!
Now I’ll leave it to the scientific researchers and philosophers to determine whether or not plants are capable of enjoying the act. But the mechanics of the act are well understood. The diagram below shows the plumbing in all its glory.
(source: Fruit & Nut Research & Information Center — http://fruitandnuteducation.ucdavis.edu/generaltopics/AnatomyPollination/Flower_Anatomy/)
The anther (the parts that hold the pollen grains) and the stamens (the long stem-like structures that support the anthers) are the flowers’ male parts. The stigma, style, ovary, and ovules are the female parts. In order for the plant to reproduce, the pollen must come in contact with the stigma. Thanks to the stickiness of the stigma, the pollen is able to stick to the stigma. Once attached to the stigma, the pollen grows a tube down through the style, into the ovary, and then unites with the ovules. This causes one half of the chromosomal makeup of the species to unite with the other half, and a seed, bearing the plants full set of chromosomes is created. In some plants, the ovary will swell after fertilization, turning into the fruits and vegetables that humans and higher animals consume for food.
How does the pollen come in contact with the stigma? In some plants this is caused by the action of the wind (e.g. corn). For others, this pollination occurs before the plant comes into full flower (e.g. beans). But the vast majority of plants are pollinated through the action of insects, birds, or bats visiting the flowers to sip the sweet nectar they produce. This is critical for two reasons – 1) some plants have male and female structures that are on separate plants. If these plants were never visited by pollinators, then these plants would never be pollinated and the species would fail to reproduce and eventually die out. 2) Approximately 80-95% of the plant species found in natural habitats require biotic agent-mediated (bees, butterflies, moths, etc.) pollination. This includes many of the fruits and vegetable plants that produce the foods critical to human health. No pollinators = no plant sex = starving humans.
So if we want to keep the human species alive, healthy, and growing, we need to protect the biotic species that help plants to “get it on.”