Pollen — Photo Gallery — National Geographic Magazine

Current Issue September 2010
Table of Contents »

- ADVERTISEMENT -

Love Is in the Air

Birds do it, bees do it, even pollinating plants do it.

/2009/12/pollen/img/01-geranium-714.jpg /2009/12/pollen/img/pollen-60-01.jpg Photograph by Martin Oeggerli Geranium The size of the grains is measured in millionths of a meter, but the romantic journeys of pollen are epic. The dozens of golden grains that have successfully reached a Geranium phaeum flower's stigma must compete to be among the few that achieve fertilization.]]> /2009/12/pollen/img/02-snowball-714.jpg /2009/12/pollen/img/pollen-60-02.jpg Photograph by Martin Oeggerli Snowball blossom Lodged in the rumpled tissue of a Viburnum tinus stigma, pollen grains from other snowball blossoms (gray) swell with moisture. One (at center) is already growing the tube that delivers sperm to the ovule. Other species' pollen (yellow and green) has landed amiss; genetic defenses exclude them from the fertilization race.]]> /2009/12/pollen/img/03-willow-714.jpg /2009/12/pollen/img/pollen-60-03.jpg Photograph by Martin Oeggerli Willow A grain of Salix caprea pollen has missed its mark. Wedged between flower petals, it will die. While some grains will be flung into the air as springtime breezes swirl the willow leaves, others will stick to the backs of bees and find their way.]]> /2009/12/pollen/img/04-composite-714.jpg /2009/12/pollen/img/pollen-60-04.jpg Composite image by Martin Oeggerli; 14 SEM scans by Ralf Buchner and Heidemarie Halbritter, University of Vienna /2009/12/pollen/img/05-quince-714.jpg /2009/12/pollen/img/pollen-60-05.jpg Photograph by Martin Oeggerli Flowering quince The convoluted surface of Chaenomeles sp. pollen may speed up moisture absorption when the grain lands on a target bloom. "Quick hydration means faster formation of the pollen tube," says Swiss photographer Martin Oeggerli, a postdoctoral fellow at University Hospital Basel. "That's important for fertilization."]]> /2009/12/pollen/img/06-clover-714.jpg /2009/12/pollen/img/pollen-60-06.jpg Photograph by Martin Oeggerli White clover Trifolium repens White clover's protein-rich pollen is an important food for bees, as is its nectar.]]> /2009/12/pollen/img/07-indian-mallow-714.jpg /2009/12/pollen/img/pollen-60-07.jpg Photograph by Martin Oeggerli Indian mallow Abutilon pictum Spines on Indian mallow pollen help it cling to bird feathers.]]> /2009/12/pollen/img/08-bromeliad-714.jpg /2009/12/pollen/img/pollen-60-08.jpg Photograph by Martin Oeggerli Bromeliad Tillandsia maxima The fold in a bromeliad grain allows it to shrink as it dries, or swell with moisture, without breaking.]]> /2009/12/pollen/img/09-cabbage-714.jpg /2009/12/pollen/img/pollen-60-09.jpg Photograph by Martin Oeggerli Water cabbage Pistia stratiotes The ridges on water cabbage grains are an unusual pollen surface feature, though the plant is common from Egypt to Argentina.]]> /2009/12/pollen/img/10-forget-me-not-714.jpg /2009/12/pollen/img/pollen-60-10.jpg Photograph by Martin Oeggerli Forget-me-not Myosotis sylvatica Forget-me-not grains are among the tiniest known, each just five one-thousandths of a millimeter across.]]> /2009/12/pollen/img/11-flytrap-714.jpg /2009/12/pollen/img/pollen-60-11.jpg Photograph by Martin Oeggerli Venus flytrap Dionaea muscipula Venus flytrap grains are more than 15 times bigger than forget-me-not ones: There's no consistent correlation between plant and pollen size.]]> /2009/12/pollen/img/12-persian-silk-714.jpg /2009/12/pollen/img/pollen-60-12.jpg Photograph by Martin Oeggerli Persian silk tree Albizia julibrissin Persian silk tree grains are also more than 15 times bigger than forget-me-not ones.]]> /2009/12/pollen/img/13-silver-leaf-714.jpg /2009/12/pollen/img/pollen-60-13.jpg Photograph by Martin Oeggerli Silver leaf tree Proteaceae Silver leaf tree grains have a sticky coating that bonds them to animal carriers.]]> /2009/12/pollen/img/14-poison-bulb-714.jpg /2009/12/pollen/img/pollen-60-14.jpg Photograph by Martin Oeggerli Poison bulb Crinum japonicum Poison-bulb pollen is surrounded by long, showy petals that attract insect porters. Some variations seem easy to explain. Others remain puzzling, or have yet to be investigated at all.]]> /2009/12/pollen/img/15-pine-714.jpg /2009/12/pollen/img/pollen-60-15.jpg Photograph by Martin Oeggerli Pine The pollen of this family coats cars with yellow-green dust—though this particular grain landed on an unhatched insect egg. It floats through the air, sperm carried by two pale "balloons." Such wind-borne pollen causes misery for allergy sufferers in much of the world, where it falls heavily, as it has for millions of years.]]>