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opencc-zeroDec 2022View details →

Data from: Range reexpansion after long stasis: Italian otters (Lutra lutra) at their northern edge

Species range shifts and expansion are subjects of primary research interest in the context of climate warming and biological invasions. Few studies have focused on reexpansion of species that suffered severe declines. Here, we focused on population recovery of Eurasian otters (Lutra lutra) in Italy, first detected in 2003 after a southward range contraction. We modelled the rate of range expansion and occupancy at the northern expanding front (central Italy), to gain insights into the progress of recovery and mechanisms of reexpansion. We performed a field survey in 2021, which redefined the northern limit of distribution further north, in close proximity to the Gran Sasso National Park. Then we analyzed a time series (1985–2021) of distances of northernmost occurrences from the centre of the 1985 range. Using segmented regression, we were able to identify a prolonged stasis of the northern range edge and a simultaneous increase in occupancy from 0.151 to 0.4. A breakpoint was estimated in 2006, after which the range expanded northwards at an average rate of 5.48 km/year. From 2006 to 2021, the overall northward shift was about 80 km. Occupancy continued to increase until 2019 and abruptly declined in 2021. These patterns suggest that the reexpansion of the range can be limited by low occupancy at the expanding front. As occupancy increases, long-distance dispersal increases and then range expands. The low occupancy at the current distribution limit of otters may reflect a higher anthropogenic pressure on northern habitats, which could slow down the reexpansion process.

opencc-zeroDec 2022View details →

Data for: A new paradigm for medium-range severe weather forecasts: Probabilistic random forest-based predictions

Historical observations of severe weather and simulated severe weather environments (i.e., features) from the Global Ensemble Forecast System v12 (GEFSv12) Reforecast Dataset (GEFS/R) are used in conjunction to train and test random forest (RF) machine learning (ML) models to probabilistically forecast severe weather out to days 4–8. RFs are trained with ~9 years of the GEFS/R and severe weather reports to establish statistical relationships. Feature engineering is briefly explored to examine alternative methods for gathering features around observed events, including simplifying features using spatial averaging and increasing the GEFS/R ensemble size with time-lagging. Validated RF models are tested with ~1.5 years of real-time forecast output from the operational GEFSv12 ensemble and are evaluated alongside expert human-generated outlooks from the Storm Prediction Center (SPC). Both RF-based forecasts and SPC outlooks are skillful with respect to climatology at days 4 and 5 with diminishing skill thereafter. The RF-based forecasts exhibit tendencies to slightly underforecast severe weather events, but they tend to be well-calibrated at lower probability thresholds. Spatially averaging predictors during RF training allows for prior-day thermodynamic and kinematic environments to generate skillful forecasts, while time-lagging acts to expand the forecast areas, increasing resolution but decreasing overall skill. The results highlight the utility of ML-generated products to aid SPC forecast operations into the medium range.

Thermal evolution of the metamorphism in the eastern Taiwan Central Range: implications for Yuli Belt exhumation

The Yuli Belt exposed in the eastern part of Taiwan’s Central Range hosts slivers of blueschist-facies meta-igneous rocks that were tectonically emplaced into a mostly greenschist-facies, polyphase deformed metasedimentary succession. Suturing the Eurasian continental plate, the subducted South China Sea plate, the proposed subducted forarc basement, and the Luzon Island arc of the Philippine Sea Plate, the Yuli Belt is a key site for understanding the geodynamic reconstruction of the Taiwan orogeny. In this paper, we reinvestigated the tectonic evolution of the Yuli Belt. The Yuli Belt of the eastern Taiwan Central Range encloses high pressure (HP) mafic–ultramafic blocks and hosts intensely deformed greenschist-facies metasediments. It is still debated if the Chulai Formation to the east is part of the Yuli Belt. To solve this problem, we provide new maximum metamorphic temperature in both units using Raman spectroscopic geo-thermometry in relation to structural deformation. The new peak metamorphic temperatures compiled with published data support systematic spatial variations across the eastern Taiwan Central Range. The Yuli Belt shows peak temperatures of ca. 400°C~550°C higher than those of adjacent units. Temperatures >500°C in the Yuli Belt are close to three HP blocks. The temperature difference between the Yuli Belt and Chulai Formation reaches over 100°C. It is likely that the contact between both units is a fault and that they underwent the same deformation history after its E-vergent backfolding phase. The new peak metamorphic temperatures compiled with published data support systematic spatial variations across the eastern Taiwan Central Range. A revised geological map was generated by the incorporation of new structural data of the metasediments from several river-transects in the eastern Central Range.

opencc-zeroJan 2023View details →

Dataset for: Efficacy of prescribed fire as a fuel reduction treatment in the Colorado Front Range

Prescribed fires are an important management tool for reducing fuels and returning fire to the landscape. However, rarely are changes in fuels fully quantified using pre- to post-prescribed fire measurements, and those studies that do exist show variable results. In the southern Rockies, little literature exists on the impacts of prescribed fires, thus we examined multiple prescribed fires in northern Colorado to understand fire effects and changes in fuel complexes. Most prominently, prescribed fires influenced litter, duff, and rotten coarse woody debris but did not influence other surface fuels. Crown base height increased and tree density decreased, while basal area was relatively unimpacted. Season of burning impacted fire effects as substrate burn severity, bole char, and crown volume scorched were highest in summer and fall. Continued monitoring of prescribed fires is critical to understand the influence of prescribed fire on wildfires and ultimately improving prescribed fire outcomes.

opencc-zeroJan 2023View details →

Range expansions of sexual versus asexual organisms: Effects of reproductive assurance and migration load

It is generally considered that sexual organisms show faster evolutionary adaptation than asexual organisms because sexuals can accumulate adaptive mutations through recombination. Yet empirical evidence often shows that the geographic range size of sexual species is narrower than that of closely-related asexual species, which may seem as if asexuals can adapt to more varied environments. Two potential explanations for this apparent contradiction considered by existing theory are reproduction assurance and migration load. Here, we consider both reproductive assurance and migration load within a single model to comparatively examine their effects on range expansions of sexuals and asexuals across an environmental gradient. The model shows that higher dispersal propensity decreases sexuals' disadvantage in reproductive assurance while increasing their disadvantage in migration load. Moreover, lower mutation rate constrains adaptation more strongly in asexuals than in sexuals. Thus, high dispersal propensity and high mutation rates promote that asexuals have wider range sizes than sexuals. Intriguingly, our model reveals that sexuals can have wider geographic range sizes than asexuals under low dispersal propensity and low mutation rates, a pattern consistent with a few exceptional empirical cases. Combining reproductive assurance and migration load provides a useful perspective to better understand the relationships between species' mating systems and their geographic ranges.

Alaska Range Suture Zone Compiled Geochronology data set

Geochronology data set for the manuscript, Upper-plate Controls on Slab Geometry, Melt Ponding, and Structurally Compelled Localized Alaska Range Suture Zone Arc Magmatism Since ca. 100 Ma, submitted to Tectonics and seismicity of Alaska and Western Canada: Earthscope and beyond."

Raw GBIF data used in the article "Climate-induced range shifts drive adaptive response via spatio-temporal sieving of alleles"

This table contains the raw (unfiltered) species occurrence data for Dianthus sylvestris complied from GBIF. A filtered subset of this data was combined with other data sources to define the input for the species distribution models used in the article "Climate-induced range shifts drive adaptive response via spatio-temporal sieving of alleles".

Data from: Protected areas not likely to serve as steppingstones for species undergoing climate-induced range shifts

Species across the planet are shifting their ranges to track suitable climate conditions in response to climate change. Given that protected areas have higher quality habitat and often harbor higher levels of biodiversity compared to unprotected lands, it is often assumed that protected areas can serve as steppingstones for species undergoing climate-induced range shifts. However, there are several factors that may impede successful range shifts among protected areas, including the distance that must be travelled, unfavorable human land uses and climate conditions along potential movement routes, and lack of analogous climates. Through a species-agnostic lens, we evaluate these factors across the global terrestrial protected area network as measures of climate connectivity, which is defined as the ability of a landscape to facilitate or impede climate-induced movement. We found that over half of protected land areas and two-thirds of the number of protected units across the globe are at risk of climate connectivity failure, casting doubt on whether many species can successfully undergo climate-induced range shifts among protected areas. Consequently, protected areas are unlikely to serve as steppingstones for a large number of species under a warming climate. As species disappear from protected areas without commensurate immigration of species suited to the emerging climate (due to climate connectivity failure), many protected areas may be left with a depauperate suite of species under climate change. Our findings are highly relevant given recent pledges to conserve 30% of the planet by 2030 (30x30), underscore the need for innovative land management strategies that allow for species range shifts, and suggest that assisted colonization may be necessary to promote species that are adapted to the emerging climate.

Range-wide whole-genome resequencing of the brown bear reveals drivers of intraspecies divergence

The brown bear is a textbook example species of the effect of Quaternary glaciation cycles on the present-day geographical distribution of mtDNA haplotypes. We compiled and analysed a range-wide whole-genome dataset of 128 brown bear individuals in order to re-evaluate brown bear population structure and genetic diversity using nuclear markers from autosomes and sex chromosomes. The file 'PLOTCOMMANDS.txt' contains detailed instructions on how to recreate the figures presented within the paper.

Data for: Prey resources are equally important as climatic conditions for predicting the distribution of a broad-ranged apex predator

Aim: A current biogeographic paradigm states that climate regulates species distributions at continental scales and that biotic interactions are undetectable at coarse-grain extents. However, advances in spatial modelling show that incorporating food resource distributions are important for improving model predictions at large distribution scales. This is particularly relevant to understand the factors limiting distribution of widespread apex predators whose diets are likely to vary across their range. Location: Neotropical Central and South America Methods: The harpy eagle (Harpia harpyja) is a large raptor, whose diet is largely comprised of arboreal mammals, all with broad distributions across Neotropical lowland forest. Here, we used a hierarchical modelling approach to determine the relative importance of abiotic factors and prey resource distribution on harpy eagle range limits. Our hierarchical approach consisted of the following modelling sequence of explanatory variables: (a) abiotic covariates, (b) prey resource distributions predicted by an equivalent modelling for each prey, (c) the combination of (a) and (b), and (d) as in (c) but with prey resources considered as a single prediction equivalent to prey species richness. Results: Incorporating prey distributions improved model predictions but using solely biotic covariates still resulted in a high performing model. In the Abiotic model, Climatic Moisture Index (CMI) was the most important predictor, contributing 76 % to model prediction. Three-toed sloth (Bradypus spp.) was the most important prey resource, contributing 64 % in a combined Abiotic-Biotic model, followed by CMI contributing 30 %. Harpy eagle distribution had high environmental overlap across all individual prey distributions, with highest coincidence through Central America, eastern Colombia, and across the Guiana Shield into northern Amazonia. Main conclusions: With strong reliance on prey distributions across its range, harpy eagle conservation programs must therefore consider its most important food resources as a key element in the protection of this threatened raptor.

Habitat and not topographic heterogeneity constrains the range sizes of African mammals

Aim: The extinction risks of species are influenced by their geographical range sizes, as species with smaller ranges are more likely to go extinct following disturbance events. Theoretically, heterogeneous landscapes can maintain small-ranged species, because they facilitate the coexistence of taxa that are each constrained to distinct abiotic conditions. However, we do not fully understand whether this process is more attributable to variation in habitat types (habitat heterogeneity) or physical elevations (topographic heterogeneity) across landscapes. Here, we compare the influences of habitat versus topographic heterogeneity on mammalian range sizes in Africa. Location: Africa. Taxon: Mammalia. Methods: We built a phylogenetic generalized least squares model to predict the range sizes of 1033 mammalian species from their functional traits and abiotic conditions. We assessed how the performance of the model changed when we incorporated measures of the local habitat and, separately, topographic heterogeneity that species experience. Results: Habitat and topographic heterogeneity are weakly correlated across Africa (ρ = 0.14). Habitat heterogeneity is inversely related to range size (model coefficient = −0.88). Incorporating habitat heterogeneity significantly decreased the model's AICc, increased its likelihood and increased the proportion of variance that is explained in the range sizes of species. Conversely, topographic heterogeneity is not significantly related to range size and had no impact on the model's AICc, likelihood or predictive performance. This contrast between habitat and topographic heterogeneity is particularly prevalent in carnivorous mammalian clades. Results at multiple spatial resolutions differed minimally. Main Conclusions: Our findings advance ecological theory by demonstrating that a landscape's variation in habitats, and not in elevations, relates inversely with mammalian range size and therefore facilitates the coexistence of small-ranged mammals. Conservation efforts in regions of high habitat heterogeneity will be critical to prevent extinctions in Africa's biodiverse mammalian species.

opencc-by-4.0Feb 2023View details →

Range Mapper Videos

Short videos showcasing Range Mapper, a new set of online interactive and animated visualizations of plant taxon range shifts in North America, Europe, and Oceania since the Last Glacial Maximum. These animated maps of taxa distributions since the last deglaciation, based upon spatiotemporal networks of fossil occurrences, offer adaptable visualizations of species range shifts in response to past climate and other environmental changes. They are designed to be useful both for experts for quick-look insights into past patterns and processes at broad scales and for educators and science communicators interested in sharing knowledge about how species adapt to changing climates. The videos show oak and spruce, hemlock, and spruce in North America, spruce and beech in Europe, and eucalyptus and nothofagus in Oceania. See our paper for more information: George, A.K., Roth, R.E., Widell, S., and Williams, J.W.. (in revision). Range Mapper: An Adaptable Process for Making and Using Interactive, Animated Web Maps of Late-Quaternary Open Paleoecological Data. Open Quaternary.

Altered trait covariances between invasive and native ranges of a global plant invader

Increasing evidence suggests that invasive populations adapt to novel environments rapidly, and the ability to rapidly adapt depends on genetically-based trait variation and covariation. However, few studies have investigated the trait covariance in the native and invasive ranges. Such investigation will give a more comprehensive picture of how historical contingency and adaptation shape invasiveness, contributing to the prediction of future invasion dynamics. Here, we collected seven and nine populations alongside latitudes from invasive and native ranges of a global invasive plant, Spartina alterniflora, and planted them in two common gardens at the southernmost and northernmost sites of the invasive range. We measured plant traits, including the first flowering time, plant height, and seed set, and analyzed how these traits varied with garden sites and populations' origin latitudes and how their covariance changed between ranges. We found that plants flowered later, grew taller, and set more seeds in the high-latitude garden than in the low-latitude one. The growth and expression of genetic variation of traits appeared to be limited by high ambient temperature in the low-latitude garden. In the high-latitude garden, the flowering time of populations showed clinal variation for both invasive and native populations, whereas the plant height and seed set showed clinal variation only for native or invasive populations. From the native to the invasive range, the flowering time and seed set developed negative genetic covariance, and flowering time and plant height changed from negative genetically correlated to uncorrelated. Our results suggested that S. alterniflora has experienced rapid adaptation to clinal and local conditions over the 40-year invasion. Such geographic-scale rapid adaptation appeared to have benefited from previously identified genetic admixture that has released the trait covariance. Our study highlights the importance of integrating full-range geographical surveys with introduction history to understand the potential and mechanisms of trait evolution during invasion.

The effect of past defaunation on ranges, niches, and future biodiversity forecasts

Humans have reshaped the distribution of biodiversity across the globe, extirpating species from regions otherwise suitable and restricting populations to a subset of their original ranges. Here, we ask if anthropogenic range contractions since the Late Pleistocene led to an under‐representation of the realized niches for megafauna, an emblematic group of taxa often targeted for restoration actions. Using reconstructions of past geographic distributions (i.e., natural ranges) for 146 extant terrestrial large‐bodied (>44 kg) mammals, we estimate their climatic niches as if they had retained their original distributions and evaluate their observed niche dynamics. We found that range contractions led to a sizeable under‐representation of their realized niches (i.e., niche unfilling). For 29 species, more than 10% of the environmental space once seen in their natural ranges has been lost due to anthropogenic activity, with at least 12 species undergoing reductions of more than 50% of their realized niches. Eighteen species mainly now be confined to low‐suitability locations, where fitness and abundance are likely diminished; we consider these taxa climatic refugees. For those species, conservation strategies supported by current ranges risk being misguided if current, suboptimal habitats are considered baseline for future restoration actions. Because most climate‐based biodiversity forecasts rely exclusively on current occurrence records, we went on to test the effect of neglecting historical information on estimates of species' potential distribution – as a proxy of sensitivity to climate change. We found that niche unfilling driven by past range contraction leads to an overestimation of sensitivity to future climatic change, resulting in 50% higher rates of global extinction, and underestimating the potential for megafauna conservation and restoration under future climate change. In conclusion, range contractions since the Late Pleistocene have also left imprints on megafauna realized climatic niches. Therefore, niche truncation driven by defaunation can directly affect climate and habitat‐based conservation strategies.

RT Dataset -- Updated radiative transfer model for Titan in the near-infrared wavelength range: Validation against Huygens atmospheric and surface measurements and application to the Cassini/VIMS observations of the Dragonfly landing area

This dataset contains all Radiative Transfer (RT) results made for the paper. The data are stored in 5 zipped-folders names with the Cassini/VIMS cube flyby and id, or explicitly for Huygens/ULIS calibrated observations: <ul> <li>TB_C1481624349_1</li> <li>T40_C1578266417_1</li> <li>T38_C1575509158_1</li> <li>T40_C1578263500_1</li> <li>T40_C1578263152_1</li> <li>ULIS_observations</li> </ul> The TB_C1481624349_1 folder contains the Cassini/VIMS cube over HLS, the HLS end-member (End_member.txt), the surface albedo retrieved by Karkoschka et al. (2016) corrected for the photometry (HLS_Karkoschka_2016_spectrum.txt), and the inverted surface albedo (Surface_albedo.txt). In these folders, each VIMS pixel is stored in a .txt file with the following pattern: <CUBE_ID>_<PIXEL_SAMPLE>_<PIXEL_LINE> .txt It starts with a header describing the observation:  <ul> <li>CUBE_ID: the VIMS cube id (`C1234567890_1` format)</li> <li>SAMPLE: the pixel sample number.</li> <li>LINE: the pixel line number.</li> <li>LONG: the pixel longitude (in degree).</li> <li>LAT: the pixel latitude (in degree).</li> <li>INC: the surface incident angle (in degree).</li> <li>EMI: the surface emergent angle (in degree).</li> <li>PHASE: the surface phase angle (in degree).</li> </ul> For the Selk crater cubes (T40_C1578266417_1, T38_C1575509158_1, T40_C1578263500_1, T40_C1578263152_1), the header also contains the spatial sampling and the radiative transfer model outputs:  <ul> <li>Spatial sampling (km/pix).</li> <li>Fh: the haze scaling factor.</li> <li>Fm: the mist scaling factor.</li> <li>1-sigma (Fh): the 1-sigma uncertainty on Fh.</li> <li>1-sigma (Fm): the 1-sigma uncertainty on Fm.</li> <li>Reduced chi2: the reduced chi2. </li> </ul> Then contains the observed spectra: <ul> <li>Column 1: the VIMS channel central wavelength (in micrometers).</li> <li>Column 2: the VIMS pixel I/F.</li> <li>Column 3: the VIMS pixel I/F 1-sigma uncertainty. </li> </ul> For the Selk crater cubes (T40_C1578266417_1, T38_C1575509158_1, T40_C1578263500_1, T40_C1578263152_1), 3 columns are added for:  <ul> <li>Column 4: the surface albedo.</li> <li>Column 5: the upper 1-sigma uncertainty on the surface albedo.</li> <li>Column 6 : the lower 1-sigma uncertainty on the surface albedo.</li> </ul> The ULIS folder contains the Huygens/ULIS calibrated observations (in I/F) and the simulations with 1-sigma uncertainties as a function of the altitude (in km): <ul> <li>Column 1: the VIMS channel central wavelength (in micrometers), stopped at the end of the Huygens/ULIS wavelength range.</li> <li>Column 2: the ULIS I/F.</li> <li>Column 3 : the simulated I/F.</li> <li>Column 4: the lower 1-sigma uncertainty on the simulation.</li> <li>Column 5 : the upper 1-sigma uncertainty on the simulation.</li> </ul>

Decoupling pioneering traits from latitudinal patterns in a North American bird experiencing a southward range shift

<ol> <li>Eco-geographic rules describe spatial patterns in biological trait variation and shed light on the drivers of such variation. In animals, a consensus is emerging that 'pioneering' traits may facilitate range shifts via a set of bold, aggressive, and stress-resilient traits. Many of these same traits are associated with more northern latitudes, and most range shifts in the northern hemisphere indicate northward movement. As a consequence, it is unclear whether pioneering traits are simply corollaries of existing latitudinal variation, or whether they override other well-trodden latitudinal patterning as a unique eco-geographic rule of phenotypic variation.</li> <li>The tree swallow (Tachycineta bicolor) is a songbird undergoing a southward range shift in the eastern United States, in direct opposition of the poleward movement seen in most other native species' range shifts. Because this organic range shift countervails the typical direction of movement, this case study provides for unique ecological insights on organisms and their ability to thrive in our changing world.</li> <li>We sampled female birds across seven populations, quantifying behavioral, physiological, and morphological traits. We also used GIS and field data to quantify a core set of ecological factors with strong ties to these traits as well as female performance.</li> <li>Females at more southern expansion sites displayed higher maternal aggression, higher baseline corticosterone, and more pronounced elevation of corticosterone following a standardized stressor, contrary to otherwise largely conserved latitudinal patterning in these traits. Microhabitat variation explained some quantitative phenotypic variation, but the expansion and historic ranges did not differ in openness, distance to water, or breeding density.</li> <li>This countervailing range shift therefore suggests that pioneering traits are not simply corollaries of existing latitudinal variation, but rather, they may override other well-trodden latitudinal patterning as a unique eco-geographic rule of phenotypic variation.</li> </ol>

A range-wide postglacial history of Swiss stone pine based on molecular markers and palaeoecological evidence

Aim: Knowing a species' response to historical climate shifts helps understanding its perspectives under global warming. We infer the hitherto unresolved postglacial history of Pinus cembra. Using independent evidence from genetic structure and demographic inference of extant populations, and from palaeoecological findings, we derive putative refugia and re-colonisation routes. Location: European Alps and Carpathians. Taxa: Pinus cembra. Methods: We genotyped nuclear and chloroplast microsatellite markers in nearly 3,000 individuals from 147 locations across the entire natural range of P. cembra. Spatial genetic structure (Bayesian modelling) and demographic history (Approximate Bayesian Computation) were combined with palaeobotanical records (pollen, macrofossils) to infer putative refugial areas during the Last Glacial Maximum (LGM) and re-colonisation of the current range. Results: We found distinct spatial genetic structure, despite low genetic differentiation even between the two disjunct mountain ranges. Nuclear markers revealed five genetic clusters aligned East–West across the range, while chloroplast haplotype distribution suggested nine clusters. Spatially congruent separation at both marker types highlighted two main genetic lineages in the East and West of the range. Demographic inference supported early separation of these lineages dating back to a previous interstadial or interglacial c. 210,000 years ago. Differentiation into five biologically meaningful genetic clusters likely established during post-glacial re-colonisation. Main conclusions: Combining genetic and palaeoecological evidence suggests that P. cembra primarily survived the LGM in "cold period" refugia south of the Central European Alps and near the Carpathians, from where it expanded during the Late Glacial into its current Holocene "warm period" refugia. This colonisation history has led to the distinct East–West structure of five genetic clusters. The two main genetic lineages likely derived from ancient divergence during an interglacial or interstadial. The respective contact zone (Brenner line) matches a main biogeographic break in the European Alps also found in herbaceous alpine plant species.

opencc-by-4.0Dec 2005View details →

Fig. 17 in Eight new species of Scrapter (Hymenoptera: Apoidea: Colletidae), with descriptions of S. albifumus and S. amplispinatus females and a major range extension of the genus

Fig. 17. Scrapter catoxys sp. n., lateral view of male.

opencc-by-4.0Dec 2005View details →

Fig. 41 in Eight new species of Scrapter (Hymenoptera: Apoidea: Colletidae), with descriptions of S. albifumus and S. amplispinatus females and a major range extension of the genus

Fig. 41. Scrapter amplispinatus Eardley, dorsal view of female.