Our planet, Earth, as it has come to be known — is the only place known to harbor life, is a pretty weird and mysterious ball of mud. We have it pretty good here. Even as we sit right on the cusp of complete annihilation, it’s really not so bad here. Protected by our thin atmosphere and fickle magnetosphere, we dodge immediate extermination by the all too occasional heat, radiation, and the insufferable sub-zero temperatures of interstellar space.
While we understand a whole lot about Earth and the life here (past and present), there’s also just so much we still don’t know or understand. One particular mystery (National Geographic has some great photos here) of life we don’t fully understand isn’t a creature at all — rather it is the absence of life that is startling. They’re called fairy circles.
Scientists back in 2004, believed they were the result of radioactivity or even termites. But alas, results came up short in several excavations and published papers detailing the lack of discovery. Others, unconvinced by previous research pressed on with the theory of termites causing the anomaly:
New research may now have yielded a more credible explanation for the fairy circles as examples of natural ecosystem engineering by a particular species of sand termites, Psammotermes allocerus. A German scientist reported on Thursday that most likely these industrious termites were the agents for making much of their desert home an oasis of permanent grassland.
Curious thing about the fairy circles, they occur pretty frequently in the deserts of Namibia. Researchers continue to go there for answers but then, something very peculiar happened. The fairy circles began cropping up in Australia.
The only thing Australia has in common with southwest Africa is the dry, arid conditions that resemble a desert. But apart from that, the two continents have been separated from each other for about 200 million years now, and the wildlife disparity couldn’t be more different.
The mystery continued to unravel and unfurl between scientists. However, nowadays there seems to be some agreement that the odd circles are a bi-product of ecosystems operating at the razors-edge for survival. Not unlike extremomophilic bacteria living in high-temperature deep-sea vents or cacti in deserts. The grasses, are just trying to organize in optimal patterns:
Many other researchers, including entomologists and botanists, aren’t convinced. They think the circles occur because plants engage in a tug-of-war for water and other scarce nutrients. Due to their battles, the landscape “self-organizes” into rings of deep-rooted grasses, draining water from a central reservoir where no other plants can thrive. This explains why, as the researchers Michael Cramer and Nichole Barger found in 2013, the fairy circles are restricted to places with low rainfall, and why they grow after dry years and shrink after wet ones.
There we have it. To be brief, there are two grass types: one that prefers to grow deep with roots on the edges of moisture and nutrients., and the other which prefers to grow in a collective matrix with shorter root structures. A slide from Cramer and Barger’s research is pretty revealing: