A small neighborhood well-organized: seasonal and daily activity patterns of the community of large and mid-sized mammals around waterholes in the Gobi Desert, Mongolia

Background Animal communities have complex patterns of ecological segregation at different levels according to food resources, habitats, behavior, and activity patterns. Understanding these patterns among the community is essential for the conservation of the whole ecosystem. However, these networks are difficult to study nowadays, due to anthropic disturbances and local extinctions, making it difficult to conclude if segregation patterns are natural or human-induced. We studied ecological segregation in a community of large and mid-sized mammals in the Great Gobi Desert, a remote arid area free from recent extinctions and human disturbances. Activity patterns of 10 sympatric mammal species were monitored around 6 waterholes through camera-trapping over a two-year period, and analyzed them primarily through circular statistics. Results Complex patterns of spatial, seasonal, and daily segregation were found. Overlap in seasonal activity was detected in only 3 of the 45 possible pairs of species. Four species used the waterholes all-year-round, while others peaked their activity during different periods. The Bactrian camel showed continuous daily activity, the grey wolf had bimodal activity, and the argali and Siberian ibex were diurnal, while the others had nocturnal peaks during different hours. Daily and spatial overlap were both detected in only 6 of the 45 pairs. Only one species pair (snow leopard and Eurasian lynx) showed an overlap at two levels: seasonal and daily. Climate and moon phase significantly affected the activity of certain species. Conclusions Altogether, the results showed complex patterns of ecological segregation at different levels in the use of the key resource in arid environments: waterholes. These results are important for understanding the biology of these species under natural conditions, as well as potential changes in altered ecosystems, and may help to design conservation strategies.

Against climate apartheid: Confronting the persistent legacies of expendability for climate justice

While the uneven causes and impacts of climate change are widely known, it is also becoming evident that many elements of the response to the climate crisis are also reinforcing discrimination, segregation, and displacement among marginalized peoples. This is entrenching a system of climate apartheid, one that is evidenced by uneven vulnerabilities to the climate crisis, as well as inequitable implementation of climate-oriented infrastructures, policies, and programs. These efforts often secure privileged populations while harming, excluding, and criminalizing populations whose lives have been made precarious by climate change. Like previous incarnations of state-sponsored “separateness,” climate apartheid is rooted in processes of colonization, racial capitalism, and hetero-patriarchy that render some populations expendable. In this paper, we show how these interlocking historical structures of oppression facilitate a response to climate change that is systematically promoting spatial, socio-economic, and ecological segregation in many mainstream attempts to safeguard economic and socio-political structures amidst global ecological catastrophe. We then offer frameworks and interventions intended to introduce meaningful pathways forward for climate justice that seek to render all life indispensable.

Manipulation of natal host modifies adult reproductive behaviour in the butterfly Heliconius charithonia

Advances in understanding non-genetic inheritance have prompted broader interest in environmental effects. One way in which such effects may influence adaptation is via the transmission of acquired habitat biases. Here I explore how natal experience influences adult host orientation in the oligophagous passion vine butterfly Heliconius charithonia . As an exemplar of the ‘pupal mating' system, this species poses novelty among diurnal Lepidoptera for the extent to which male as well as female reproductive behaviours are guided by olfactory host cues. I sampled wild adult females breeding exclusively upon Passiflora incarnata , assigned their offspring to develop either upon this species or its local alternative Passiflora suberosa , and then assessed the behaviour of F 1 adults in a large rainforest enclosure. Despite the fact that juvenile performance was superior upon P. incarnata , females oviposited preferentially upon their assigned natal species. Mate-seeking males also indicated a bias for the proximity of their natal host, and there was evidence for assortative mating based upon host treatment, although these data are less robust. This study is, to my knowledge, the first to support Hopkins' hostplant principle in butterflies, and points to inducible host preferences capable of reinforcing ecological segregation and ultimately accelerating evolutionary divergence in sympatry.

Mild segregation in the breeding preferences of an invasive anuran (Discoglossus pictus) and its main native competitor (Epidalea calamita) in ephemeral ponds

The choice of breeding sites by pond-breeding anurans has notable consequences for the fitness of larvae. Hence, beyond pond typology and phenology, adults can also discriminate according to several other features, for instance to favour allotopy with potential competitors. However, the lack of shared evolutionary history might impede proper ecological differentiation with alien species during the first stages of invasions. Here, we studied several possible sources of ecological segregation between the invasive Discoglossus pictus and the native Epidalea calamita in ephemeral ponds, where the native toad hardly had competition before the arrival of the invasive frog. During spring of 2016, we periodically surveyed 69 ephemeral ponds in three areas with different invasion histories to detect the presence/absence of eggs and tadpoles of these species. Invasive D. pictus started breeding earlier than E. calamita, but differences were not significant. Similarly, there were not clear differences among areas with different invasion histories. However, we found for both species a mutual tendency to directly avoid larval syntopy at the end of the reproductive season. We also found interspecific differences in the features that both species use for pond choice, preferring the native species shallower and less vegetated ephemeral ponds. Globally however, co-occurrence was high, pointing at other processes as key to the coexistence between both species in these habitats.

Microhabitat segregation among three co-existing species of grasshoppers on a rural meadow near Seoul, South Korea

Microhabitat segregation among grasshopper species in Asia has not been well studied. We determined the differences in the use of substrates by three common North East Asian grasshopper species co-existing on a natural meadow near Seoul, South Korea. While many Oedaleusinfernalis individuals were found on the ground, Acridacinerea and Atractomorphalata were usually observed on plants. Acridacinerea was mostly observed on the grass Zoysiajaponica (Poaceae) and Atractomorphalata was mostly found on plants from the family Asteraceae. This is the first study to provide quantitative information about microhabitat differences among some common grasshoppers in rural habitats of continental North East Asia. Future studies should focus on determining the mechanisms that produce such ecological segregation.