To Purify Their Sap

Luckily not all or even most wind-borne pollens are venomous. Almost no one, for instance, is ever hurt by pine pollen, although it is extremely abundant in spring, and, provided with big air sacs, it has astounding buoyancy—so great indeed that pine pollen has been found on the snows of Greenland, although the nearest pine forests are four hundred miles away across open sea in Labrador. Nor is there much credence to be placed in the old wives' tale of "rose colds." For practically all the flowers with conspicuous petals and fragrance are exclusively insect-pollinated. Their pollen is quite un-adapted to wind transport, and normally is never recovered from the atmosphere.

Every child today can instruct his parents in the facts of life from the analogy of the bees and the pollen of flowers. Yet only three hundred years ago the wisest scientists did not know that plants have sex. Or, rather, mankind had forgotten it again, for the Egyptians and Babylonians knew it when they pollinated their date palms by hand. So even the great Renaissance anatomist Malpighi informed his classes that plants rid themselves of pollen to purify their sap!

It was not until 1793 that Pastor Konrad Sprengel discovered in Germany that insects transport pollen from flower to flower. Regarding this as God's prettiest little miracle, he spent so much time in the fields studying flowers and bees that he would forget to come to his fashionable church and preach a sermon, so his congregation dropped him. He was so far ahead of his scientific times that scientists failed to recognize his work till Darwin unearthed it sixty years later.

It was Darwin who first showed that many kinds of flowers have elaborate ways of preventing inbreeding by their own pollen. In some the female organ or pistil is actually infertile to pollen grains from one of its own stamens, and will not produce seed when sprinkled with its own pollen. In certain flowers the stamens ripen before the pistil, in others the pistil ripens before the stamens; hence, for fertilization to take place, the pollen must come from some other plant of the same species whose stamens have ripened later or earlier.

The best all-around pollinator is the common honeybee, which is abroad earlier in spring than any other flower-loving insect, and is the last to leave the field in fall. It has the habit of sticking faithfully to one kind of flower, at least for a while, unlike the butterflies that sip at one kind of blossom after another. The pollen the honeybee carries is therefore likely to arrive at its intended destination—a female flower of the same species. This is important because of the short life of pollen.

By: davidbunch

Article Directory: http://www.articledashboard.com

Other articles: temporary job agencies Jobs Princess Cruise Line fbi agent salary