July 1, 2012 1:07
From the south of Angola to the northern part of South Africa, stretching thousands of empty land round spots with a diameter of two to twelve meters, which are often surrounded by perimeter unusually high grass. Consider their local traces of the gods, and scientists are just shrug.
Biologist Walter Tschinkel of Florida State University in Tallahassee (USA) does not pretend to answer to the mystery, but he had found something very interesting.
When the technician first demonstrated this phenomenon — and that was in 2005, in a private nature reserve Namibian NamibRand, — he immediately suspected that the situation in the termites that eat the roots of grass or produce toxic gases. However, excavations carried out in 2007, revealed no traces of termites. Furthermore, the addition of nutrients in these circles has not led to growth of a grass — so it's not in their absence.
Then Mr. Tschinkel turned to satellite imagery. Comparing photos taken in four years, he came to the conclusion that — as a hypothesis — has already spoken: circles are alive! Extrapolating the data, an expert has estimated that the smallest rise and fall every 24 years, while the large "live" up to 75 years. Life expectancy — 41 years.
Then came the analysis of information provided by the administration of the reserve NamibRand. The fact that enterprising land owners sell circles ecotourists for $ 50 each. The deal, of course, symbolic: the owners reported the geographical coordinates of the spot to which they can then enjoy using Google Earth.
Park rangers regularly photographed sold plots and images taken in recent years, Mr. Tschinkel has estimated that the average life expectancy of a community of about 60 years.
Unfortunately, researchers who have found time for this community, you can count on one hand, and, as a rule, their experiments were carried out in haste. Unfortunately, no one has yet studied them seriously.
In the future, Mr. Tschinkel plans to return to the reserve and run tests at different times of the year: it seems that the circles are usually formed after the rainy season.