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Data from: Association between stock market gains and losses and Google searches
Experimental studies in the area of Psychology and Behavioral Economics have suggested that people change their search pattern in response to positive and negative events. Using Internet search data provided by Google, we investigated the relationship between stock-specific events and related Google searches. We studied daily data from 13 stocks from the Dow-Jones and NASDAQ100 indices, over a period of 4 trading years. Focusing on periods in which stocks were extensively searched (Intensive Search Periods), we found a correlation between the magnitude of stock returns at the beginning of the period and the volume, peak, and duration of search generated during the period. This relation between magnitudes of stock returns and subsequent searches was considerably magnified in periods following negative stock returns. Yet, we did not find that intensive search periods following losses were associated with more Google searches than periods following gains. Thus, rather than increasing search, losses improved the fit between people's search behavior and the extent of real-world events triggering the search. The findings demonstrate the robustness of the attentional effect of losses.
Data from: Obesity-induced decreases in muscle performance are not reversed by weight loss
BACKGROUND/OBJECTIVES: Obesity can affect muscle phenotypes, and may thereby constrain movement and energy expenditure. Weight loss is a common and intuitive intervention for obesity, but it is not known whether the effects of obesity on muscle function are reversible by weight loss. Here we tested whether obesity-induced changes in muscle metabolic and contractile phenotypes are reversible by weight loss. SUBJECTS/METHODS: We used zebrafish (Danio rerio) in a factorial design to compare energy metabolism, locomotor capacity, muscle isometric force and work-loop power output, and myosin heavy chain (MHC) composition between lean fish, diet-induced obese fish, and fish that were obese and then returned to lean body mass following diet restriction. RESULTS: Obesity increased resting metabolic rates (Po0.001) and decreased maximal metabolic rates (P = 0.030), but these changes were reversible by weight loss, and were not associated with changes in muscle citrate synthase activity. In contrast, obesity-induced decreases in locomotor performance (P = 0.0034), and isolated muscle isometric stress (P = 0.01), work-loop power output (Po0.001) and relaxation rates (P = 0.012) were not reversed by weight loss. Similarly, obesity-induced decreases in concentrations of fast and slow MHCs, and a shift toward fast MHCs were not reversed by weight loss. CONCLUSION: Obesity-induced changes in locomotor performance and muscle contractile function were not reversible by weight loss. These results show that weight loss alone may not be a sufficient intervention.
Data from: Regional drivers of clutch loss reveal important trade-offs for beach-nesting birds
Coastal birds are critical ecosystem constituents on sandy shores, yet are threatened by depressed reproductive success resulting from direct and indirect anthropogenic and natural pressures. Few studies examine clutch fate across the wide range of environments experienced by birds; instead, most focus at the small site scale. We examine survival of model shorebird clutches as an index of true clutch survival at a regional scale (∼200 km), encompassing a variety of geomorphologies, predator communities, and human use regimes in southeast Queensland, Australia. Of the 132 model nests deployed and monitored with cameras, 45 (34%) survived the experimental exposure period. Thirty-five (27%) were lost to flooding, 32 (24%) were depredated, nine (7%) buried by sand, seven (5%) destroyed by people, three (2%) failed by unknown causes, and one (1%) was destroyed by a dog. Clutch fate differed substantially among regions, particularly with respect to losses from flooding and predation. 'Topographic' exposure was the main driver of mortality of nests placed close to the drift line near the base of dunes, which were lost to waves (particularly during storms) and to a lesser extent depredation. Predators determined the fate of clutches not lost to waves, with the depredation probability largely influenced by region. Depredation probability declined as nests were backed by higher dunes and were placed closer to vegetation. This study emphasizes the scale at which clutch fate and survival varies within a regional context, the prominence of corvids as egg predators, the significant role of flooding as a source of nest loss, and the multiple trade-offs faced by beach-nesting birds and those that manage them.
Data from: Range contraction and increasing isolation of a polar bear subpopulation in an era of sea-ice loss
Climate change is expected to result in range shifts and habitat fragmentation for many species. In the Arctic, loss of sea ice will reduce barriers to dispersal or eliminate movement corridors, resulting in increased connectivity or geographic isolation with sweeping implications for conservation. We used satellite telemetry, data from individually marked animals (research and harvest), and microsatellite genetic data to examine changes in geographic range, emigration, and interpopulation connectivity of the Baffin Bay (BB) polar bear (Ursus maritimus) subpopulation over a 25-year period of sea-ice loss. Satellite telemetry collected from n = 43 (1991–1995) and 38 (2009–2015) adult females revealed a significant contraction in subpopulation range size (95% bivariate normal kernel range) in most months and seasons, with the most marked reduction being a 70% decline in summer from 716,000 km2 (SE 58,000) to 211,000 km2 (SE 23,000) (p < .001). Between the 1990s and 2000s, there was a significant shift northward during the on-ice seasons (2.6° shift in winter median latitude, 1.1° shift in spring median latitude) and a significant range contraction in the ice-free summers. Bears in the 2000s were less likely to leave BB, with significant reductions in the numbers of bears moving into Davis Strait (DS) in winter and Lancaster Sound (LS) in summer. Harvest recoveries suggested both short and long-term fidelity to BB remained high over both periods (83–99% of marked bears remained in BB). Genetic analyses using eight polymorphic microsatellites confirmed a previously documented differentiation between BB, DS, and LS; yet weakly differentiated BB from Kane Basin (KB) for the first time. Our results provide the first multiple lines of evidence for an increasingly geographically and functionally isolated subpopulation of polar bears in the context of long-term sea-ice loss. This may be indicative of future patterns for other polar bear subpopulations under climate change.
Data from: Loss of animal seed dispersal increases extinction risk in a tropical tree species due to pervasive negative density dependence across life stages
Overhunting in tropical forests reduces populations of vertebrate seed dispersers. If reduced seed dispersal has a negative impact on tree population viability, overhunting could lead to altered forest structure and dynamics, including decreased biodiversity. However, empirical data showing decreased animal-dispersed tree abundance in overhunted forests contradict demographic models which predict minimal sensitivity of tree population growth rate to early life stages. One resolution to this discrepancy is that seed dispersal determines spatial aggregation, which could have demographic consequences for all life stages. We tested the impact of dispersal loss on population viability of a tropical tree species, Miliusa horsfieldii, currently dispersed by an intact community of large mammals in a Thai forest. We evaluated the effect of spatial aggregation for all tree life stages, from seeds to adult trees, and constructed simulation models to compare population viability with and without animal-mediated seed dispersal. In simulated populations, disperser loss increased spatial aggregation by fourfold, leading to increased negative density dependence across the life cycle and a 10-fold increase in the probability of extinction. Given that the majority of tree species in tropical forests are animal-dispersed, overhunting will potentially result in forests that are fundamentally different from those existing now.
Data from: Trait-associated loss of frugivores in fragmented forest does not affect seed removal rates
Seed dispersal by frugivorous animals forms the basis for regeneration of numerous plant species. Habitat fragmentation has been found to be one major factor perturbing frugivore communities and dependent plant species. Yet, community-wide consequences of fragmentation for both frugivore and plant communities are still hardly understood. Here, we studied the effects of habitat fragmentation on the seed removal by frugivorous birds and mammals from nine fleshy-fruited plant species in Białowieża Forest (Eastern Poland). This last relict of old-growth lowland forest in Europe poses an exceptional reference site for studying the impact of habitat fragmentation on seed dispersal processes in temperate forest ecosystems. In particular, (i) we tested for associations between forest fragmentation and response traits of frugivores, that is forest specialization and body mass; (ii) we studied the relationship between frugivore response and effect traits, that is centrality (number of consumed plant species) and interaction type (mutualistic vs. antagonistic); and (iii) we assessed the feedback of fragmentation-induced changes on plant–frugivore interactions and seed removal rates. We found that fragmentation led to shifts in the frugivore community, associated with the response traits forest specialization and body mass, with fewer forest specialists and large-bodied frugivores in fragmented than in continuous forests. However, forest generalists and small-bodied frugivores were more central in the plant–frugivore associations than forest specialists and large-bodied frugivores. Therefore, the loss of vulnerable species did not result in reduced seed removal rates in fragmented compared with continuous forest. Synthesis. These results indicate that seed removal may be relatively robust in spite of shifts in the frugivore community in forest fragments. The correlation between response and effect traits of frugivores highlights the importance of forest generalists and small-bodied frugivores for maintaining dispersal processes in fragmented forests in temperate regions. Yet, future studies should aim at quantifying the consequences of seed disperser loss on other aspects of dispersal, such as long-distance dispersal, spatial patterns of seed deposition, seed germination and plant regeneration.
Data from: Non-random loss of phylogenetically distinct rare species degrades phylogenetic diversity in semi-natural grasslands
1. Although biodiversity loss is a critically important topic, our understanding of how both land abandonment and land-use intensification in semi-natural grasslands alters the community diversity and assembly mechanisms is very limited. Large-scale economic drivers of land-use change might inadvertently result in the loss of vulnerable species and reduce ecosystem services provisioning. 2. In this study, we assessed non-random community change by examining patterns of low-abundance species loss, and community assembly in semi-natural grasslands due to land abandonment and intensification in southwest Japan. We analyzed relationships between evolutionary distinctiveness and abundance for each species. In addition, we used metrics of species and phylogenetic diversity and phylogenetic structure to assess patterns of non-random biodiversity loss due to both abandoned and intensified land-use. 3. We demonstrated that low-abundance species were more evolutionarily distinct compared to high-abundance (i.e., dominant) species. Furthermore, land-use intensification resulted in further declines in low-abundance species, whereas land abandonment resulted in declines in all species, regardless of their initial abundance. 4. We found that both forms of land-use change (abandonment and intensification) resulted in non-random patterns of community change, with traditional land-use maintaining the highest biodiversity and land-use change coinciding with decreased species and phylogenetic diversity measures. Intensified land-use caused phylogenetic community structure to be more closely related than expected by chance, whereas the metrics of how distant species are from one another on average based on phylogenetic tree (i.e., mean pairwise phylogenetic distance) did not change from land abandonment. 5. Synthesis and applications. We show that the loss of phylogenetic diversity, and especially of low-abundance species with high value of phylogenetic distinctiveness, resulted in non-random community disassembly. Our results argue that in order to maintain biodiversity in these semi-natural grasslands, traditional management practices should be encouraged over intensification and simple abandonment. Government agencies should adopt policies or provide incentives that encourage the maintenance of traditional practices in rural Japan, and elsewhere where the combination of land consolidation and abandonment are important conservation issues.
Data from: Primary rainforest amount at the landscape scale mitigates bird biodiversity loss and biotic homogenization
1.Tropical conservation strategies traditionally focus on large tracts of pristine forests, but given rapid primary forest decline, understanding the role of secondary forest remnants for biodiversity maintenance is critical. Until now, the interactive effects of changes in forest amount, configuration and disturbance history (secondary vs. primary forest) on the conservation value of tropical landscapes has remained unknown, hampering the incorporation of these global change drivers into local and global conservation planning. 2.We disentangled effects of landscape wide forest amount, fragment size, and forest age (old growth versus secondary forest) on abundance, α-diversity, β-diversity (biotic homogenisation) and community shifts of bird communities in human-dominated landscapes of southern Costa Rica. Utilizing two complementary methods, yielding 6900 individual detections and 223 species, we characterized bird communities in 49 forest fragments representing independent gradients in fragment size (<5 ha vs >30 ha) and forest amount (5%-80%) in the surrounding landscape (within 1000 m). 3.Abundance and α-diversity of forest specialists and insectivores declined by half in small fragments, but only in landscapes with little old growth forest. Conversely, secondary forest at the landscape scale showed no such compensation effect. Similarly, a null-model approach indicated significant biotic homogenisation in small versus large fragments, but only in landscapes with little old growth forest, suggesting forest amount and configuration interactively affect β-diversity in tropical human-dominated landscapes. Finally, dramatic abundance-based community shifts relative to intact forests are largely a result of landscape-scale loss of old growth rather than changes in overall forest cover. 4.Policy implications. Our study provides strong evidence that retaining old growth within tropical human modified landscapes can simultaneously curb erosion of avian forest specialist α-diversity, mitigate collapse of β-diversity (biotic homogenisation) and dampen detrimental avian community shifts. However, secondary forests play, at best, a subordinate role to mitigate these processes. To maintain tropical forest biodiversity, retaining old growth forest within landscapes should be first priority, highlighting a land-sparing approach.
Data from: Step-patterned survivorship curves: mortality and loss of equilibrium responses to high temperature and food restriction in juvenile rainbow trout (Oncorhynchus mykiss)
<p>While survivorship curves typically exhibit smooth declines over time, step-patterned curves can occur with multiple stressors within a life stage. To explore this process, we examined the effects of heat (24 ºC) and food restriction on juvenile rainbow trout (<i>Oncorhynchus mykiss</i> Walbaum) in challenge experiments. We observed step-patterned survivorship curves determined by mortality and loss of equilibrium (LOE) endpoints. To examine the cause of heterogeneity in the stress responses from early to late mortality and LOE, we measured indices of energetic reserves. The step transition in the survivorship curves, the peak mortality rates, and start of when individuals reached a critical energetic threshold (14% dry mass; 4.0 kJ·g<sup>-1</sup> energy) all occurred at around days 10-15 of the challenge. The coherence in these temporal patterns suggest heterogeneity in the cohort stress responses, in which an early subgroup died from heat stress and a late subgroup died from starvation. Thus, their endpoint sensitivities resulted in step-patterned survivorship curves. We discuss the implications of the study for understanding effects of multiple stressors on population heterogeneity and note the possible significance of stress response selection under climate change in which heat stress and food limitations occur in concert.</p>
Data from: Feeding the enemy: loss of nectar and nectaries to herbivores reduces tepal damage and increases pollinator attraction in Iris bulleyana
Floral nectar usually functions as a pollinator reward, yet it may also attract herbivores. However, the effects of herbivore consumption of nectar or nectaries on pollination have rarely been tested. We investigated Iris bulleyana, an alpine plant that has showy tepals and abundant nectar, in the Hengduan Mountains of SW China. In this region, flowers are visited mainly by pollen-collecting pollinators and nectarivorous herbivores. We tested the hypothesis that, in I. bulleyana, sacrificing nectar and nectaries to herbivores protects tepals and thus enhances pollinator attraction. We compared rates of pollination and herbivory on different floral tissues in plants with flowers protected from nectar and nectary consumption with rates in unprotected control plants. We found that nectar and nectaries suffered more herbivore damage than did tepals in natural conditions. However, the amount of tepal damage was significantly greater in the flowers with protected nectaries than in the controls; this resulted in significant differences in pollinator visitation rates. These results provide the first evidence that floral nectar and nectaries may be 'sacrificed' to herbivores, leading to reduced damage to other floral tissues that are more important for reproduction.
Data from: Loss of heterosis and family-dependent inbreeding depression in plant performance and resistance against multiple herbivores under drought stress
1. Inbreeding depression (ID), outbreeding depression (OD) and heterosis can occur concurrently in plant populations. ID often increases under environmental stress, but the combined effects of inbreeding, outbreeding between populations and environmental stress, such as drought, on plant performance and herbivore resistance remain unclear. 2. In order to determine environment-dependent and family-dependent ID, OD and heterosis we conducted a common garden experiment with plants from five populations of Brassica nigra. Inbred, within-population outbred and between-population outbred plant families were exposed to drought or ambient water levels. We recorded the abundance and damage caused by specialist herbivores from contrasting feeding guilds, i.e. the phloem-feeding Brevicoryne brassicae, the leaf-chewing Psylliodes chrysocephalus and the stem-boring Ceutorhynchus quadridens larvae. 3. Drought stress had negative effects on growth, herbivore resistance and resistance against B. brassicae and positive effects on investments in reproductive output and plant secondary metabolites (sinigrin). We found drought stress-induced loss of heterosis for plant height and investment in reproductive output. Between-population outbred plants were more sensitive to drought stress in terms of above-ground biomass compared to within-population outbred plants. 4. Drought and inbreeding synergistically negatively influenced traits related to growth and reproductive output (environment-dependent inbreeding depression, EDID). There was high variation among families within populations in the degree of ID and EDID. Genetic variation in EDID could buffer the negative effects of genetic stress associated with habitat fragmentation and concurrent environmental stress. In order to capture fully the effects of both inbreeding and between-population outbreeding under stress the different spatial scales of the effects of inbreeding and between-population outbreeding should be taken into account. 5. Synthesis. Our results indicate that drought stress influences not only inbreeding depression (ID), but also heterosis. These findings shed new light on the combined effects of anthropogenic environmental change and the genetic consequences of habitat fragmentation on plants and their interactions with other organisms. Conservation programmes aiming to restore genetically degraded populations with the translocation of individuals between populations should consider environmental stress as a risk factor.
Data from: Intensive forest harvesting increases susceptibility of northern forest soils to carbon, nitrogen and phosphorus loss
1. Understanding the impact of forest harvesting is critical to sustainable forest management, yet there remains much uncertainty regarding how harvesting affects soil carbon (C), nitrogen (N) and phosphorus (P) dynamics. 2. Here we conducted a global meta-analysis of 808 observations from 49 studies to test the effects of harvesting on the stocks and concentrations of soil C, N, and P and C:N:P ratios relative to uncut control stands. 3. With all harvesting intensities combined, C stock was unaffected by harvesting in either the forest floor or mineral soil, while harvesting reduced forest floor [C], [N], and [P] and C:N ratio, increased the mineral soil [C] and C:N ratio, but reduced mineral soil N stock,. The impacts of harvesting on forest floor C and N stocks, C:P and N:P and mineral soil [C] and [N] changed from no effects by partial, stem-only and whole-tree harvesting to significantly negative effects by the harvesting coupled with fire. Stem-only and whole-tree harvesting similarly reduced forest floor [P]. The negative effects of harvesting were most pronounced in conifer stands. Soil [C], [N] and C:N decreased with time since harvesting, but soil [P] did not, resulting in an increase in forest floor N:P. 4. Synthesis and applications. Our findings highlight the importance of harvest intensity and rotation length on long-term soil nutrient availability when managing forests. Furthermore, the lag in [P] recovery following harvesting may indicate a decoupling of the P cycle from that of C and N and a potential concern in managed forests.
Data from: Natural habitat loss and exotic plants reduce the functional diversity of flower visitors in a heterogeneous subtropical landscape
1. Functional diversity (FD) of pollinators can increase plant reproductive output and the stability of plant-pollinator communities. Yet, in times of worldwide pollinator declines, effects of global change on pollinator FD remain poorly understood. Loss of natural habitat and exotic plant invasions are two major drivers of global change that particularly threaten pollinator diversity. 2. In a subtropical South African landscape, we investigated changes in the FD of flower visitor assemblages on native and exotic plants along gradients of natural habitat loss and relative abundance of exotic plants. We used a dataset of 1434 flower visitor individuals sampled on 131 focal plants and calculated the FD in three flower visitor traits that are strongly related to plant-flower visitor interactions and pollination processes: proboscis length, proboscis diameter and body length. 3. Multivariate FD of flower visitors decreased with both increasing natural habitat loss and relative exotic abundance. Importantly, changes in FD went beyond those in flower visitor richness. Furthermore, flower visitor richness was not related to either natural habitat loss or relative exotic abundance. Loss in multivariate FD seemed to be mediated by complementary reductions of FD in proboscis length with natural habitat loss and of FD in body length with both global change drivers. Correspondingly, we recorded lower abundances of long-tongued flower visitors with natural habitat loss and reduced variance in body size with both drivers. In contrast, FD in proboscis diameter was unaffected by either driver. All effects of the two global change drivers were non-interactive. 4. Our results show that both natural habitat loss and exotic plants negatively affect flower visitor FD, which may imperil pollination of specialised plant species in degraded habitats. In contrast, flower visitor richness may not cover all facets of flower visitor FD that are relevant to pollination processes, and here future studies are needed. Distinct responses of visitor traits to the two drivers suggest limited options to infer relations of one trait to another. Finally, additive effects of natural habitat loss and exotic plant invasions highlight the need to consider multiple drivers of global change when investigating ecosystem processes at a community scale.
Data from: Functional diversity loss with increasing livestock grazing intensity in drylands: the mechanisms and their consequences depend on the taxa
1. Overgrazing is one of the main drivers of desertification in drylands, and livestock production is expected to increase in the next decades. The analysis of functional diversity can clarify the effects of increasing livestock grazing on ecosystem functioning. 2. We assess the effect of livestock grazing intensity on the relationship between taxonomic (TDH) and functional diversity (FDQ) of plants, ants and small mammals, as well as on within-trait diversity. We compared results using two indices of taxonomic diversity (Shannon and Simpson). We used structural equation modelling (SEM) to assess the causal relationship between grazing intensity, TDH, FDQ and decomposition rate for each taxa. 3. Correlation between TDH vs. FDQ varied across assemblages and seasons, but was consistent between different indices of taxonomic diversity. A similar trajectory of TDH vs. FDQ under land-use intensification was found for all taxa, with a correlated loss of species and functional traits. Also, within-trait diversity was negatively affected by increasing grazing pressure. Vegetation and small mammal SEM models show that increasing grazing intensity had a strong and direct effect on decomposition rate. The ant SEM model was the only one that showed an indirect effect of grazing on decomposition through FDQ. TDH had no effect on decomposition for either taxa. 4. We found higher niche differentiation in animal than in plant assemblages. In vegetation, several species seem to have similar trait diversity (i.e. redundancy), perhaps due to a dominant role of environmental constraints. These results were consistent among diversity indices. But increasing disturbance negatively affected TDH vs. FDQ in all assemblages in a similar way. Livestock grazing affected decomposition rate directly, and indirectly only through the effect of ants FDQ. 5. Synthesis and applications. Under increasing grazing intensity all plant and animal assemblages respond with a mirrored reduction in taxonomic and functional diversity, although vegetation seems to have higher functional redundancy. Our results are robust to diversity indices, showing that several taxa respond similarly to land-use intensification, despite differences in the mechanism behind it. This may facilitate sustainable management. Notably, increasing grazing intensity affects decomposition rate through a stronger direct than indirect effect. The stronger direct effect of livestock on decomposition rate, rather than indirectly through functional diversity, suggests that changes in structure may be more important than changes in community composition.
Data from: Sexual signal loss: the link between behavior and rapid evolutionary dynamics in a field cricket
1. Sexual signals may be acquired or lost over evolutionary time, and are tempered in their exaggeration by natural selection. 2. In the Pacific field cricket, Teleogryllus oceanicus, a mutation ("flatwing") causing loss of the sexual signal, the song, spread in < 20 generations in two of three Hawaiian islands where the crickets have been introduced. Flatwing (as well as some normal-wing) males behave as satellites, moving towards and settling near calling males to intercept phonotactic females. 3. From 2005-2012, we surveyed crickets and their responses to conspecific song, noting the morph and number of males and females before and after experimental playbacks. The three Hawaiian islands consistently contained different proportions of flatwing crickets, ranging from about 90% of males on Kauai to 50% on Oahu to rare on the Big Island of Hawaii. 4. Flatwing and normal-wing males do not appear to differ in responsiveness to playback, a behavior that should influence the likelihood of a male encountering a phonotactic female. Instead, male and female crickets from populations in which little to no calling song is perceptible during development tended to seek out callers more readily than crickets that developed in noisier environments. Such increased phonotaxis makes females more likely to find either the caller to which they are responding or to encounter a flatwing (or normal male satellite) that has also been attracted to the song. 5. Our evidence suggests that pre-existing behavioral plasticity (manifest as flexible responses to social – particularly acoustic – information in the environment) is associated with the rapid spread of the flatwing trait. Different social environments select for differential success of flatwing or normal-wing males, which in turn alters the social environment itself.
Data from: Ecological gradients drive insect wing loss and speciation: the role of the alpine treeline
Alpine ecosystems are frequently characterised by an abundance of wing-reduced insect species, but the drivers of this biodiversity remain poorly understood. Insect wing reduction in these environments has variously been attributed to altitude, temperature, isolation, habitat stability, or decreased habitat size. We used fine-scale ecotypic and genomic analyses, along with broad-scale distributional analyses of ecotypes, to unravel the ecological drivers of wing reduction in the wing-dimorphic stonefly Zelandoperla fenestrata complex. Altitudinal transects within populations revealed dramatic wing reduction over very fine spatial scales, tightly linked to the alpine treeline. Broad biogeographic analyses confirm that the treeline has a much stronger effect on these ecotype distributions than altitude per se. Molecular analyses revealed parallel genomic divergence between vestigial-winged (high altitude) and full-winged (low altitude) ecotypes across distinct streams. These data thus highlight the role of the alpine treeline as a key driver of rapid speciation, providing a new model for ecological diversification along exposure gradients
Data from: Integrated radar and lidar analysis reveals extensive loss of remaining intact forest on Sumatra 2007–2010
Forests with high above ground biomass (AGB), including those growing on peat swamps, have historically not been thought suitable for biomass mapping and change detection using Synthetic Aperture Radar (SAR). However, by integrating L-band (λ = 0.23 m) SAR with lidar data from the ALOS and ICESat earth-observing satellites respectively, and 56 forest plots, we were able to create a forest biomass and change map for a 10.7 Mha section of eastern Sumatra that still contains high AGB peat swamp forest. Using a time series of SAR data we estimated changes in both forest area and AGB. We estimate that there were 274 ± 68 Tg AGB remaining in natural forest (≥ 20 m height) in the study area in 2007, with this stock reducing by approximately 11.4% over the subsequent 3 years. A total of 137.4 kha of the study area were deforested between 2007 and 2010; an average rate of 3.8% yr−1. The ability to attribute forest loss to different initial biomass values allows for far more effective monitoring and baseline modelling for avoided deforestation projects than traditional, optical-based remote sensing. Furthermore, given SAR's ability to penetrate the smoke and cloud which normally obscure land cover change in this region, SAR-based forest monitoring can be relied on to provide frequent imagery. This study demonstrates that even at L-band, which typically saturates at medium biomass levels (ca. 150 Mg ha−1), it is possible to make reliable estimates of not just the area but the carbon emissions resulting from land use change.
Data from: The loss of functional diversity: a detrimental influence of landscape-scale deforestation on tree reproductive traits
1. Agricultural activities such as crop production and cattle ranching are rapidly replacing forests worldwide, especially in the tropics. Resulting forest loss can adversely affect biodiversity in many ways, including trajectories of community reassembly, community composition, forest structural profiles, and taxonomic diversity. Yet, effects of forest loss on specific ecosystem functions remain limited. Processes closely linked with tree reproduction, such as pollination and seed dispersal are of paramount importance for many ecological functions in tropical forests. Disruption in these processes is known to delay or change forest regeneration, diversity, and structural dynamics. 2. To explore how reproductive and dispersal traits are being altered by landscape-scale deforestation, we surveyed and compiled trait data for tree communities in 20 tropical Atlantic rainforest remnants in northeastern Brazil, across a gradient of deforested landscapes, each retaining 3 to 93% forest cover. 3. The functional richness of reproductive plant attributes decreased as the amount of forest cover decreased, while divergence increased along the same gradient. Loss of forest cover disproportionately affected certain dispersal and reproductive attributes, with most heavily impacted functional attributes including: brief flowering duration, hermaphrodite sexual system, and zoochoric dispersal mode. We identified a clear threshold at 25-30% of forest cover, below which, reproductive attributes disappeared more quickly than expect from forest remnants. 4. Synthesis. Deforestation may impair tree community functional diversity, particularly by decreasing the number of functions and increasing certain functional reproductive attributes that are particularly successful in disturbed habitats. Under scenarios of extensive deforestation, changes to reproductive and dispersal trait profile of forest communities suggest that profound modifications in the availability of floral and seed resources are likely to be substantial. Such extensive changes to food supply of pollinating and dispersing animals suggest carry-over effects to the fauna of these important forest systems.
Data from: Stepping-stone expansion and habitat loss explain a peculiar genetic structure and distribution of a forest insect
It is challenging to unravel the history of organisms with highly scattered populations. Such species may have fragmented distributions because extant populations are remnants of a previously more continuous range, or because the species has narrow habitat requirements in combination with good dispersal capacity (naturally or vector borne). The northern pine processionary moth Thaumetopoea pinivora has a scattered distribution with fragmented populations in two separate regions, northern and south-western Europe. The aims of this study were to explore the glacial and postglacial history of T. pinivora, and add to the understanding of its current distribution and level of contemporary gene flow. We surveyed published records of its occurrence and analysed individuals from a representative subset of populations across the range. A 633 bp long fragment of the mtDNA COI gene was sequenced and nine polymorphic microsatellite loci were genotyped. Only nine nucleotide sites were polymorphic in the COI gene and 90% of the individuals from across its whole range shared the same haplotype. The microsatellite diversity gradually declined towards the north, and unique alleles were found in only three of the northern and three of southern sites. Genetic structuring did not indicate complete isolation among regions, but an increase of genetic isolation by geographic distance. Approximate Bayesian model choice suggested recent divergence during the postglacial period, but glacial refugia remain unidentified. The progressive reduction of suitable habitats is suggested to explain the genetic structure of the populations and we suggest that T. pinivora is a cold-tolerant relict species, with situation-dependent dispersal.
Data from: Elevated CO2 and temperature increase soil C losses from a soybean-maize ecosystem
Warming temperatures and increasing CO2 are likely to have large effects on the amount of carbon stored in soil, but predictions of these effects are poorly constrained. We elevated temperature (canopy: +2.8 °C; soil growing season: +1.8 °C; soil fallow: +2.3 °C) for 3 years within the 9th–11th years of an elevated CO2 (+200 ppm) experiment on a maize–soybean agroecosystem, measured respiration by roots and soil microbes, and then used a process-based ecosystem model (DayCent) to simulate the decadal effects of warming and CO2 enrichment on soil C. Both heating and elevated CO2 increased respiration from soil microbes by ~20%, but heating reduced respiration from roots and rhizosphere by ~25%. The effects were additive, with no heat × CO2 interactions. Particulate organic matter and total soil C declined over time in all treatments and were lower in elevated CO2 plots than in ambient plots, but did not differ between heat treatments. We speculate that these declines indicate a priming effect, with increased C inputs under elevated CO2 fueling a loss of old soil carbon. Model simulations of heated plots agreed with our observations and predicted loss of ~15% of soil organic C after 100 years of heating, but simulations of elevated CO2 failed to predict the observed C losses and instead predicted a ~4% gain in soil organic C under any heating conditions. Despite model uncertainty, our empirical results suggest that combined, elevated CO2 and temperature will lead to long-term declines in the amount of carbon stored in agricultural soils.
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Allen Brain Atlas
Allen Brain Atlas is an Allen Institute collection of brain map atlases, datasets, APIs, and analysis tools covering mouse, human, and non-human primate brain resources.
Annotated Behaviour and Observability Dataset (ABODe)
ABODe is a University of Edinburgh DataShare dataset for behavior classification in group-housed mice using home-cage video, identities, bounding boxes, ground-plate positions, and annotator labels.
DANDI Archive for NWB datasets
DANDI is a BRAIN Initiative archive for publishing and sharing neurophysiology data, including electrophysiology, optophysiology, and behavioral data packaged as NWB and related standards.
International Brain Laboratory public data
The International Brain Laboratory public data releases expose standardized mouse decision-making experiments, including Neuropixels recordings, widefield calcium imaging, behavior, and session metadata accessed through the ONE API.
OpenNeuro
OpenNeuro is a free, open platform for sharing neuroimaging datasets, with public search, dataset pages, and download paths for web, S3, DataLad, and the OpenNeuro CLI.