text: Patterns appearing on both the very large and very small scale are rare in nature. But researchers have found such a pattern in two apparently unrelated places - cells in human skin, and the mysterious fairy circles in Namibia. While the distribution of desert fairy circles may look random, as if the landscape is marked with freckles, the pattern closely matches the distribution pattern of skin cells. Researchers have found a similar pattern in two apparently unrelated places - skin cells and the mysterious fairy circles in the Namibian desert. The illustration on the left shows the distribution of skin cells, and the one on the right plots fairy circles, which are also arranged in polygons . ‘It's a completely amazing, strange match,’ said Professor Robert Sinclair, head of the Mathematical Biology Unit at Okinawa Institute of Science and Technology Graduate University (OIST) in Japan. Desert fairy circles are considered one of nature's greatest mysteries because no one knows how they form. Found in Namibia, they are large barren patches of earth measuring anywhere between 10ft and 65ft in diameter (three metres to 20 metres) that are ringed by short grass dotting the scrub land like craters on the moon, or big freckles. Several teams of scientists are trying to explain the bizarre markings, and suggestions have included termites nibbling grass, zebras rolling in circles, competition for resources, hydrocarbons emanating from the depths of the earth to kill off patches of vegetation and even aliens. Desert fairy circles (pictured) are considered one of nature's greatest mysteries because it is now known how they form. Found in Namibia, they are large barren patches of earth ringed by short grass dotting the desert like craters on the moon, or big freckles . Now, Professor Sinclair and Haozhe Zhang believe they have identified a small, but vital, piece of the puzzle by comparing their distribution to skin cells. The duo compared the number of 'neighbours' adjacent to fairy circles and skin cells, according to the study published in Ecological Complexity. They used satellite images of fairy circles and a computer to draw lines halfway between each pair to give them invisible boundaries that look similar to cell walls. The majority of skin cells and fairy circles both had six 'neighbours', and similar percentages of other neighbours (shown in this graph) The computer then counted how many neighbours surrounded each fairy circle. Another group of researchers had calculated skin cell neighbours in a similar way several years ago, which was used as a comparison. The experts found that the results were almost identical, in that both the majority of skin cells and fairy circles had six neighbours. And the percentage of fairy circles with four, five, six, seven, eight and nine neighbours was essentially the same as the skin cells. ‘I didn't expect it to be so close,’ Professor Sinclair said. ‘We spent a lot of time checking because it really looked too close to believe.’ Mr Zhang, a PhD student at Iowa State University who was previously at OISTsaid that future mathematical models designed to explain how fairy rings are made should incorporate the results of this study. The researchers suspect the patterns might be similar because both skin cells and fairy circles are fighting for space. Professor Sinclair said: ‘It is still difficult to say why exactly they are similar, but the fact that they are similar is already very important. ‘This is suggesting there may be such types of patterns that cover really different size scales.’ Huge swathes of grassland in Namibia is covered with mysterious vegetation-free patches that have been baffling scientists for decades. While a number of studies have suggested the fairy circles are created by industrious termites, research last May claimed they are the result of resource competition for water among plants. German researchers analysed the spatial distribution of the fairy circles and found that they are ‘remarkably regular’ in their distribution, which made them question the termite theory. Experts from various institutions have previously claimed that termites nibble away at grassroots in certain grasslands of southwest Africa, causing the dieback of vegetation and creating a water trap. Last year, German researchers analysed the spatial distribution of the fairy circles (pictured in the Marienfluss Valley) and found that they are 'remarkably regular' in their distribution. There is a no vegetation growth within the circular area . The genesis of a fairy circle has not been observed. Their occurrence appears to be restricted to particularly arid zones at the border of grassland and desert regions, according to the study published in the journal Ecography, where there is intense resource-competition for water. Dr Getzin's team was joined by experts from Göttingen in Germany, Italy and Israel who studied aerial images of the circles in north west Namibia to pinpoint the location and distribution of the barren patches within the surrounding landscape. Using statistical methods, they found that the circles are distributed regularly across large areas. ‘The occurrence of such patterning in nature is rather unusual. There must be particularly strong regulating forces at work,’ Dr Getzin said. He believes it is the local resource-competition among plants and vegetation, in a similar way to how young trees space themselves out in forests to ensure they have access to enough nutrients and water. ‘A similar process of resource-competition may consequently also be the real cause for a self-organising formation of the mysterious fairy circle patterns,’ the study says. The scientists simulated underground competition for water and the spatial vegetation distribution patterns. They found that similar patterns emerged on the screen to those recorded in Namibia.
target: It is not known how fairy circles in the Namibian desert are made .
  Clue may lie in the distribution of the barren circles of Earth in grassland .
  Researchers in Japan discovered their distribution is similar to skin cells .
  Like human cells, the mysterious circles typically have six 'neighbours'