Biogeography

The global biogeography and environmental drivers of fairy circles

Fairy circles (FCs) are intriguing regular vegetation patterns that have only been described in Namibia and Australia so far. We conducted a global and systematic assessment of FC-like vegetation patterns and discovered hundreds of FC-like locations on three continents. We also characterized the range of environmental conditions that determine their presence, which is restricted to narrow and specific soil and climatic conditions. Areas showing FC-like vegetation patterns also had more stable productivity over time than surrounding areas having non-FC patterns. Our study provides insights into the ecology and biogeography of these fascinating vegetation patterns and the first atlas of their global distribution.

Density-dependence of reproductive success in a Houbara bustard population.

Although density-dependent processes and their impacts on population dynamics are key issues in ecology and conservation biology, empirical evidence of density-dependence remains scarce for species or populations with low densities, scattered distributions, and especially for managed populations where densities may vary as a result of extrinsic factors (such as harvesting or releases). Here, we explore the presence of density-dependent processes in a reinforced population of North African Houbara bustard (Chlamydotis undulata undulata). We investigated the relationship between reproductive success and local density, and the possible variation of this relationship according to habitat suitability using three independent datasets. Based on eight years of nests monitoring (more than 7000 nests), we modeled the Daily Nest Survival Rate (DNSR) as a proxy of reproductive success. Our results indicate that DNSR was negatively impacted by local densities and that this relationship was approximately constant in space and time: (1) although DNSR strongly decreased over the breeding season, the negative relationship between DNSR and density remained constant over the breeding season; (2) this density-dependent relationship did not vary with the quality of the habitat associated with the nest location. Previous studies have shown that the demographic parameters and population dynamics of the reinforced North African Houbara bustard are strongly influenced by extrinsic environmental and management parameters. Our study further indicates the existence of density-dependent regulation in a low-density, managed population.

Biogeography of global drylands

Here we synthesize the biogeography of key organisms (vascular and non‐vascular vegetation and soil microorganisms), attributes (functional traits, spatial patterns, plant‐plant and plant‐soil interactions) and processes (productivity and land cover) across global drylands. We finish our review discussing major research gaps, which include: i) studying regular vegetation spatial patterns, ii) establishing large‐scale plant and biocrust field surveys assessing individual‐level trait measurements, iii) knowing whether plant‐plant and plant‐soil interactions impacts on biodiversity are predictable and iv) assessing how elevated CO2 modulates future aridity conditions and plant productivity.

Ecological Diversity within Rear-Edge: A Case Study from Mediterranean Quercus pyrenaica Willd.

Understanding the ecology of populations located in the rear edge of their distribution is key to assessing the response of the species to changing environmental conditions. Here, we focus on rear-edge populations of Quercus pyrenaica in Sierra Nevada (southern Iberian Peninsula) to analyze their ecological and floristic diversity. We perform multivariate analyses using high-resolution environmental information and forest inventories to determine how environmental variables differ among oak populations, and to identify population groups based on environmental and floristic composition.

Late-spring frost risk between 1959 and 2017 decreased in North America but increased in Europe and Asia

Frost in late spring causes severe ecosystem damage in temperate and boreal regions. We here analyze late-spring frost occurrences between 1959 and 2017 and woody species’ resistance strategies to forecast forest vulnerability under climate change. Leaf-out phenology and leaf-freezing resistance data come from up to 1,500 species cultivated in common gardens. The greatest increase in leaf-damaging spring frost has occurred in Europe and East Asia, where species are more vulnerable to spring frost than in North America. The data imply that 35 and 26% of Europe’s and Asia’s forests are increasingly threatened by frost damage, while this is only true for 10% of North America. Phenological strategies that helped trees tolerate past frost frequencies will thus be increasingly mismatched to future conditions.

Potential changes in the distribution of Carnegiea gigantea under future scenarios

The goals of this study are to provide a map of actual habitat suitability (1), describe the relationships between abiotic predictors and the saguaro distribution at regional extents (2), and describe the potential effect of climate change on the spatial distribution of the saguaro (3).

Past and potential future population dynamics of three grouse species using ecological and whole genome coalescent modeling

Here we investigated the demographic history of the willow grouse (Lagopus lagopus), rock ptarmigan (Lagopus muta), and black grouse (Tetrao tetrix) through the Late Pleistocene using two complementary methods and whole genome data. Species distribution modeling (SDM) allowed us to estimate the total range size during the Last Interglacial (LIG) and Last Glacial Maximum (LGM) as well as to indicate potential population subdivisions.

Phylogenetic age differences in tree assemblages across the Northern Hemisphere increase with long-term climate stability in unstable regions

Our results show that phylogenetically diverse assemblages with large phylogenetic age differences among species are associated with relatively high long‐term climate stability, with intra‐regional links between long‐term climate variability and phylogenetic composition especially strong in the more unstable regions. These findings point to future climate change as a key risk to the preservation of the phylogenetically diverse assemblages in regions characterized by relatively high paleoclimate stability, with China as a key example.

Historical anthropogenic footprints in the distribution of threatened plants in China

In this study, for the first time, we linked the distribution of threatened species across China to current and historical changes in human population densities, cropland area, and pasture area since 1700 (at a 100 km × 100 km resolution). We find that variables describing historical changes in human impacts were consistently more strongly associated with proportions of threatened plants than variables describing current changes in human impacts. Notably, threatened plant species in China tend to be concentrated where historical anthropogenic impacts were relatively small, but anthropogenic activities have intensified relatively strongly since 1700.

The ecological niche and distribution of Neanderthals during the Last Interglacial

This paper [was highlighted in the *Editor's Picks* section of the Science Journal](https://www.dropbox.com/s/6k308eczv7i6kbj/2017_BMB_Journal_of_Biogeography_editors_choice.pdf?dl=1), and was among the [top downloaded articles](https://www.dropbox.com/s/sowq1h4bdngmipy/2017_BMB_Journal_of_Biogeography.png?dl=1) from the *Journal of Biogeography* during the 12 months after its publication.