valley Like
heuweltjies in South Africa and
Mima mounds in the U.S., the cause of fairy circles has long been a puzzle and the investigation has proved challenging. There may also be more than one explanation, as fairy circles in Namibia may be created in a different way from those in Australia, because they formed on
sand rather than
clay. In 2012, Eugene Moll suggested the
termite species
Baucaliotermes hainsei and
Psammotermes allocerus as the creator of these circles. All rings have been found to contain termite casts, and
radar investigations suggest that a moist layer of soil is situated beneath the fairy circles. In 2013, this theory was supported by Norbert Juergens. Juergens found evidence that the sand termite,
Psammotermes allocerus, generates a local ecosystem that profits from and promotes the creation of the fairy circle. Juergens responded that sand termites differ from harvester termites and live deep beneath the circle; they do not create mounds or nests above ground, and they leave no tracks in the sand. They examined the conditions under which fairy circles arise and found that fairy circles are negatively correlated with precipitation and soil nutrition. This observation is consistent with resource competition being a cause of the circles. Grassy landscapes with a mixture of grasses can result in barren spots as a consequence of under-ground competition between different types of grasses. The patches are maintained because they form a reservoir of nutrients for the taller grasses at the periphery. Using rainfall, biomass and temperature seasonality, they can predict with high accuracy the presence or absence of fairy circles in a region. According to Walter Tschinkel, this theory accounts for all the characteristics of fairy circles, including the presence of tall grass species. In May 2014, Getzin et al. demonstrated that termite or gas activity cannot explain the extremely regular spacing of the fairy circles, but the patterns are congruent with typical patterns resulting from vegetation self-organization. However, a large meta analysis of worldwide insect and fairy circle patterns in drylands confirmed earlier conclusions, showing that nest patterns of termites differ significantly from fairy circles. The spatially periodic (Turing-like) pattern of fairy circles is a typical example of vegetation self-organization in desert regions. A 2015 theory about the Australian fairy circles suggested that the distinct vegetation patterns are a population-level consequence of competition for scarce water, as the plants "organise" themselves to maximise access to scarce resources. The circular barren patches capture water which then flows to the outer edges of the ring. More water available increases
biomass and roots which leads to the soil becoming looser. The less dense soil allows more water to penetrate and feed the vegetation, creating a
feedback loop supporting the plants at the edge of the circle. Field observations by Sujith Ravi,
Lixin Wang and colleagues using soil moisture, soil particle size, and soil water infiltration measurements in Namibia in 2015 and 2016 support this. In 2021, an explanation using hydrological feedbacks and the
Turing mechanism was proposed as the cause of the patterns in Australia. In 2022, a study was published that tested the termite theory and the theory of plant self-organization for Namibia by excavating hundreds of grasses within and around the fairy circles. The study revealed that the grasses within fairy circles died of plant-water stress but not due to root herbivory by termites because the roots were initially undamaged and as long or even longer than the roots of the vital grasses outside. Several fairy circle researchers stated that "The new study showed "conclusively" that termites were not a factor". In 2024, it was shown that the topsoil within the fairy circles is significantly drier than outside in the matrix and that new emerging seedlings quickly die in fairy circles due to desiccation. In February 2025, Cramer and Tschinkel published a review article about all fairy circle theories. They emphasize that the self-organization of vegetation is the only theory that is consistent with all field observations, while all other theories have serious shortcomings. in the
Northern Territory An Australian cross-cultural study published in April 2023, involving local Martu peoples and using their traditional knowledge of the phenomenon, are pavement nests occupied by
Drepanotermes (
Australian harvester termites). The research showed that the circles may have been created in the
Pleistocene (over 12,000 years ago), and that termites lived in them and were continuing to build them. Aboriginal peoples have lived on the Australian continent for up to 65,000 years and have deep knowledge passed down through their
oral traditions. Thus, Australian fairy circles and termite linyji are different and not caused by the same mechanism.
Birth and death One interesting phenomenon of fairy circles is their "birth and death", that is, their appearance and disappearance over time. In some cases, fairy circles have disappeared within a span of 10 years or less, while other fairy circles may have lasted for centuries. These births and deaths, taken over long time spans, can lead to
regime shifts, such as
desertification of this ecosystem. This means that these events may be indicative of a large-scale transformation of this landscape, so that observing fairy circles birth is indicative of a gradual desertification process taking place. Scientists have tried to test if such birth or death can occur due to intervention, for instance by changing the amount of water in the system. This, in turn, can potentially help determine the true cause of fairy circles.
Myths In the
oral myths of the
Himba people of the
Kunene Region of northern Namibia, these barren patches are said to have been caused by the gods, spirits and/or natural divinities. The region's
bushmen have traditionally ascribed spiritual and magical powers to them. Of specific beliefs, the Himba people note that their original ancestor, Mukuru, was responsible for the creation of the fairy circles, or that they were the footprints of gods. Another myth put forth, promoted by some tour guides in Namibia, is that the circles are formed by a
dragon in the earth and that its poisonous breath kills the vegetation. == Use ==