Fairy Circles
Strange circles where no plants grow occur in parts of Africa and Australia. With no apparent explanation, whimsical folks suggested it’s where rings of fairies dance. Now, scientists are fighting over less fascinating explanations. These circles occur in areas with low annual rainfall and little variety of plant life such as Namibia and the outbacks of Australia. Further, in some areas the circles sprinkle themselves into hexagonal patterns.
Until recently, it was thought that termites might be responsible,
Now, some scientists believe that the competition for water among plants is responsible with the explanation coming from a mathematical theory of pattern formation for the shapes and dispersion.
One article describes how the amount of rainfall needs to be just right and that the soil becomes compacted and clay-like inside the circles so that rain runs off to the perimeter of the circle sustaining the plants there. I’ve written a blog about how plants compete for resources, roots spreading out and invading the space of rival plants, but somehow recognize their own kind and respectfully share the moisture. This does suggest the kinds of plants would influence the growth pattern. Since the variety of plant life is limited in regions where fairy circles are found I would expect that areas around individual plants would be barren if their neighbors are like them, i.e. there would be circles around them. Further, when I see plants growing out of thin cracks in rocks, which can’t gather much rainfall, it’s hard to believe it’s just a matter of not enough moisture in the circles. Therefore, this explanation puzzles me.
Some scientists believe that it is a combination of the termites and sparse rainfall.
Somehow I don’t think we’ve heard the last word on why there are fairy circles, but I enjoyed writing about a light, fun topic for a change.
ewritessite---Eloise Hamann 