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 45 dipterocarps DHJanzen100988.jpg high resolution
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| Wind dispersal is a bit more than simply evolutionarily tacking a wing onto a seed and letting it fall. This can be illustrated with the wind-dispersed fruits of various species of large rainforest trees from Malaysia in the Dipterocarpaceae. Each of these fruits is from a different species growing in approximately the same area of forest. The ruler is 15 cm long. Even if all these species released their fruits from the same height in the same intensity of wind, each would create a different seed shadow - some small and concentrated around the base of the parent tree, with a downwind bias, to some that covered many thousands of square meters and are wildly distorted from an elipse in the downwind area. Now, add to that irregularity that in fact some are released from very tall trees above the general canopy, while other species are released in the canopy - with the attendant problems of banging into other foliage as they begin their flight. Finally, some require very dry weather and a very strong turbulent wind to break free from the parent tree, while others fall free at the slightest shaking of the branch. | ||
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