Four Pollen Grains

Pollen grains were the great Angiosperm plant innovation to free themselves from water-dependent reproduction and dispersal. Male pollen could fly lightly into the stratosphere and travel huge distances, in this watertight sealed spaceship of hope for the future generation. But over 99% of these pollen grains do not land on the female stigma and perish. It is simply a matter of chance where they land. Also, the exact simultaneous timing of the launch of the pollen and the availability of the receptive female gynoecium is critical. They both have to be ready at the same time. The less than 1% of the pollens that do survive and fertilize the gynoecium have thus travelled against extreme odds. This sculpture shows the structural variety of four types of flower pollen grains.