The future of fog‐dependent habitats under climate change is unknown but likely precarious; many have experienced recent declines in fog. Fog‐dependent deserts particularly will be threatened, because, there, fog can be the main water source for biota. We review the interactions between fog and fauna of the Namib Desert, about which there is 50 yr of research. We resynthesize the data, seeking patterns and mechanisms that could provide a framework for predicting outcomes of changes in fog regime in other fog‐dependent deserts. In the Namib, fog constitutes the most‐predictable form of free water. At least 48 Namib animal species consume free water from fog, or are likely to do so, employing both liquid and vapor phase. Fog also sustains plants that form the base for metabolic water production and wets the diet to provide pre‐formed water. So fog provides or underpins all the water intake of Namib fauna. Only a few species are active fog‐harvesters, though. Among Namib beetles, two species are unique in that they fog‐bask; they assume stereotyped postures in wind‐driven fog and droplets deposit on their carapaces. Some Namib beetle species construct surface ridges that trap fog water, which they consume. Some arthropods emerge from their subsurface habitats, or occupy its wet top layers, to access fog water, at times and in conditions outside their usual surface activity. Many more taxa, including vertebrates, use fog water opportunistically. They do not actively seek it out but use it when available. Acquiring fog water from droplets requires overcoming spherical surface tension so is possible only for animals heavier than ~100 mg. Smaller animals extract water from films or acquire it in the vapor phase. Some Namib animals use hygroscopic surfaces to extract vapor from unsaturated air, at ambient humidities attained in fog or sometimes between fogs. Rapid acquisition of water during episodic fog events creates problems for storage and osmoregulation, which some Namib animals have solved in enterprising ways, including long‐term internal storage of water and sequestering of osmolytes. Although not yet comprehensive, the body of research reviewed, and the principles that we have elucidated underlying fog usage, should inform future research on fauna throughout fog‐dependent deserts.

We document changes in rangeland during a prolonged drought in the arid Karoo. Rangeland in this arid region is species-rich and dominated by a mixture of long-lived succulent and non-succulent shr...

Tierberg-LTER is a research site established in 1987 in the semi-arid Succulent Karoo near Prince Albert in the Western Cape province, South Africa. The original purpose for its establishment was to study ecosystem dynamics and the drivers of vegetation in the context of historical land use. The large body of work that has materialised from Tierberg-LTER is grounded on extensive baseline data and has greatly influenced the broader Karoo literature. It stands as the only long-term ecological research facility for the semi-arid region of South Africa. The Karoo environment faces several new developments centred largely on the expanding energy sector. Under a changing climate, ecosystems will have to further adapt to the impacts of such developments. The future research programme for Tierberg-LTER will accordingly continue to focus on understanding Karoo ecosystem dynamics and drivers of climate and anthropogenic change at local scales, thereby informing management and mitigation of future development impact...

1. Circular bare patches occur in high numbers among the vegetation of the Namib Desert margin. There is an ongoing scientific debate on the origin of these so‐called “fairy circles” (FCs). One of the most frequently discussed hypotheses regards the bare patches to be the result of localised herbivory by sand termites of the genus Psammotermes (family Rhinotermitidae). 2. In all earlier publications, the fairy circles of the Namib Desert region within their entire range from Angola through Namibia to South Africa were, in principle, regarded to be of one type, albeit increasing in size towards the north. Here we present evidence that at −16.23° latitude there is an abrupt discontinuity which separates the FCs on either side from each other. 3. South of this discontinuity all studied FCs share the properties of the previously described fairy circles in Namibia and South Africa, especially the presence of Psammotermes termites . 4. In contrast, north of −16.23°S the FCs are much larger and are caused by a different and undescribed termite species, most closely related to the harvester termite genus Microhodotermes (family Hodotermitidae). The two sets of fairy circles differ in a specific set of morphological features, associated termites, and soil parameters. 5. The observed juxtaposition of the newly discovered large structures caused by a hodotermitid termite and the Psammotermes FCs caused by a rhinotermitid species is interpreted as an interesting example of convergent evolution resulting in similar ecological structures.