Aim: The aim was to assess the sensitivity of butterfly population dynamics to variation in weather conditions across their geographical ranges, relative to sensitivity to density dependence, and determine whether sensitivity is greater towards latitudinal range margins. Location: Europe.Time period: 1980-2014.Major taxa studied: Butterflies.Methods: We use long-term (35 years) butterfly monitoring data from > 900 sites, ranging from Finland to Spain, grouping sites into 28 latitudinal bands. For 12 univoltine butterfly species with sufficient data from at least four bands, we construct population growth rate models that include density dependence, temperature and precipitation during distinct life-cycle periods, defined to accommodate regional variation in phenology. We use partial R 2 values as indicators of butterfly population dynamics' sensitivity to weather and density dependence, and assess how these vary with latitudinal position within a species' distribution.

If current trends continue, the tropical forests of the Anthropocene will be much smaller, simpler, steeper and emptier than they are today. They will be more diminished in size and heavily fragmented (especially in lowland wet forests), have reduced structural and species complexity, be increasingly restricted to steeper, less accessible areas, and be missing many heavily hunted species. These changes, in turn, will greatly reduce the quality and quantity of ecosystem services that tropical forests can provide. Driving these changes will be continued clearance for farming and monoculture forest plantations, unsustainable selective logging, overhunting, and, increasingly, climate change. Concerted action by local and indigenous communities, environmental groups, governments, and corporations can reverse these trends and, if successful, provide future generations with a tropical forest estate that includes a network of primary forest reserves robustly defended from threats, recovering logged and secondary forests, and resilient community forests managed for the needs of local people. Realizing this better future for tropical forests and people will require formalisation of land tenure for local and indigenous communities, better-enforced environmental laws, the widescale roll-out of payments for ecosystem service schemes, and sustainable intensification of under-yielding farmland, as well as global-scale societal changes, including reduced consumerism, meat consumption, fossil fuel reliance, and population growth. But the time to act is now, while the opportunity remains to protect a semblance of intact, hyperdiverse tropical forests.

The importance of parasites as a selective force in host evolution is a topic of current interest. However, short-term ecological studies of host-parasite systems, on which such studies are usually based, provide only snap-shots of what may be dynamic systems. We report here on four surveys, carried out over a period of 12 years, of helminths of spiny mice (Acomys dimidiatus), the numerically dominant rodents inhabiting dry montane wadis in the Sinai Peninsula. With host age (age-dependent effects on prevalence and abundance were prominent) and sex (female bias in abundance in helminth diversity and in several taxa including Cestoda) taken into consideration, we focus on the relative importance of temporal and spatial effects on helminth infracommunities. We show that site of capture is the major determinant of prevalence and abundance of species (and higher taxa) contributing to helminth community structure, the only exceptions being Streptopharaus spp. and Dentostomella kuntzi. We provide evidence that most (notably the Spiruroidea, Protospirura muricola, Mastophorus muris and Gongylonema aegypti, but with exceptions among the Oxyuroidae, e.g. Syphacia minuta), show elements of temporal-site stability, with a rank order of measures among sites remaining similar over successive surveys. Hence, there are some elements of predictability in these systems.

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Habitat conversion is a major driver of tropical biodiversity loss, but its effects are poorly understood in montane environments. While community-level responses to habitat loss display strong elevational dependencies, it is unclear whether these arise via elevational turnover in community composition and interspecific differences in sensitivity or elevational variation in environmental conditions and proximity to thermal thresholds. Here we assess the relative importance of inter-and intraspecific variation across the elevational gradient by quantifying how 243 forest-dependent bird species vary in sensitivity to landscape-scale forest loss across a 3000-m elevational gradient in the Colombian Andes. We find that species that live at lower elevations are strongly affected by loss of forest in the nearby landscape, while those at higher elevations appear relatively unperturbed, an effect that is independent of phylogeny. Conversely, we find limited evidence of intraspecific elevational gradients in sensitivity, with populations displaying similar sensitivities to forest loss, regardless of where they exist in a species' elevational range.Gradients in biodiversity response to habitat loss thus appear to arise via interspecific gradients in sensitivity rather than proximity to climatically limiting conditions.