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The design of a pine cone allowing aerodynamic pollination to take place is one of a myriad of interesting plant reproduction techniques.
Botanists classify pine trees as gymnosperms – a term which literally means “naked seed.” The ovule which contains the egg is not enclosed in a container as in most other plants. The ovule is within the scales of the familiar pine cone. Actually, the woody pine cone which people are most familiar with, is the female pine cone. The male pine cones are much smaller and they produce the pollen. The reason for the name “cone” is that in some varieties it is cone shaped. Botanists call them strobili.
The pine cone ovule has an open end called a micorpyle which carries the sperm from the pollen to the egg. The small male cones grow in clusters and have pollen-producing chambers which release pollen into the air. The problem is how to get pollen from the male cones to the micropyle of the female cones by wind alone.
Karl J. Nicklas at Cornell University has discovered that female pine cones are “aerodynamically designed to filter large amounts of pollen from the air.” Using helium-filled bubbles and a wind tunnel, he was able to show that the shape of the interior area of the pine cone funnels wind so that the wind’s contents will be deposited right on top of the micropyle. Wouldn’t this pattern deposit everything on top of the micropyle, including dust and pollen from other kinds of plants?
Each plant’s cone has a slightly different shape from every other kind of plant. In addition to that, each plant’s pollen has a different size and density. Because of this design, only one density and volume will accumulate right at the micropyle. All other densities will end up somewhere else in the cone, but not where it needs to be to reach the ovule and fertilize the seed.
Another interesting design feature is the fact that the male pine cones tend to be more heavily concentrated near the bottom of the tree and the female cones concentrated closer to the top. This seems to be counter-intuitive. Wouldn’t you expect the female cones to be below the male cones so that they can catch the pollen as it falls down? You would, except that cross-pollination between trees is desirable. It would be rare that the wind would blow the pollen upward to the same tree. However, the wind could cause pollen to drift upward before reaching another tree where it could pollinate the cones there.
The fact that those who study these features see them as an indication of a high level of design shows that intelligence is involved in the process. To see this design as merely a product of chance takes a great amount of faith in chance. We see it as another Dandy Design of the grand Designer.
References-
Scientific American, July 1987, pages 90-95
“conifer cone,” Wikipedia
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