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Data from: The challenge of accurately documenting bee species richness in agroecosystems: bee diversity in eastern apple orchards
Bees are important pollinators of agricultural crops, and bee diversity has been shown to be closely associated with pollination, a valuable ecosystem service. Higher functional diversity and species richness of bees have been shown to lead to higher crop yield. Bees simultaneously represent a mega-diverse taxon that is extremely challenging to sample thoroughly and an important group to understand because of pollination services. We sampled bees visiting apple blossoms in 28 orchards over 6 years. We used species rarefaction analyses to test for the completeness of sampling and the relationship between species richness and sampling effort, orchard size, and percent agriculture in the surrounding landscape. We performed more than 190 h of sampling, collecting 11,219 specimens representing 104 species. Despite the sampling intensity, we captured <75% of expected species richness at more than half of the sites. For most of these, the variation in bee community composition between years was greater than among sites. Species richness was influenced by percent agriculture, orchard size, and sampling effort, but we found no factors explaining the difference between observed and expected species richness. Competition between honeybees and wild bees did not appear to be a factor, as we found no correlation between honeybee and wild bee abundance. Our study shows that the pollinator fauna of agroecosystems can be diverse and challenging to thoroughly sample. We demonstrate that there is high temporal variation in community composition and that sites vary widely in the sampling effort required to fully describe their diversity. In order to maximize pollination services provided by wild bee species, we must first accurately estimate species richness. For researchers interested in providing this estimate, we recommend multiyear studies and rarefaction analyses to quantify the gap between observed and expected species richness.
Data from: Interactions among trees: a key element in the stabilising effect of species diversity on forest growth
1.There is mounting evidence that species diversity increases the temporal stability of forest growth. This stabilising effect of diversity has mainly been attributed to species differences in their response to fluctuating environmental conditions. Interactions among individuals could also contribute to the stabilising effect of diversity by increasing the mean and reducing the variance of tree growth, however, this has never been directly demonstrated. 2.We used tree‐ring width chronologies from temperate and boreal mixed stands of Eastern Canada to identify the role of interactions among individuals in the stabilising effect of diversity on forest growth. Using neighbourhood competition index and a mixed model we compared the effect of interspecific and intraspecific interactions on the mean and the variance of tree growth. 3.We found that interspecific interactions are less detrimental to tree growth than intraspecific interactions. We also found that interspecific interactions buffer tree response to drought and thereby reduce the variance of tree growth. 4.Our results indicate diversity may increase the mean and reduce the variance of tree growth through interactions among individuals. Thus, we demonstrate interactions among individuals play a role in the stabilising effect of diversity on forest growth, and in doing so, we bring to light other mechanisms of the insurance hypothesis.
Data from: Discovery of an unknown diversity of Leucinodes species damaging Solanaceae fruits in sub-Saharan Africa and moving in trade (Insecta, Lepidoptera, Pyraloidea)
The larvae of the Old World genera Leucinodes Guenée, 1854 and Sceliodes Guenée, 1854 are internal feeders in the fruits of Solanaceae, causing economic damage to cultivated plants like Solanum melongena and S. aethiopicum. In sub-Saharan Africa five nominal species of Leucinodes and one of Sceliodes occur. One of these species, the eggplant fruit and shoot borer L. orbonalis Guenée, 1854, is regarded as regularly intercepted from Africa and Asia in Europe, North and South America and is therefore a quarantine pest on these continents. We investigate the taxonomy of African Leucinodes and Sceliodes based on morphological characters in wing pattern, genitalia and larvae, as well as mitochondrial DNA, providing these data for identification of all life stages. The results suggest that both genera are congeneric, with Sceliodes syn. n. established as junior subjective synonym of Leucinodes. L. orbonalis is described from Asia and none of the samples investigated from Africa belong to this species. Instead, sub-Saharan Africa harbours a complex of eight endemic Leucinodes species. Among the former nominal species of Leucinodes (and Sceliodes) from Africa, only L. laisalis (Walker, 1859), comb. n. (Sceliodes) is confirmed, with Leucinodes translucidalis Gaede, 1917, syn. n. as a junior subjective synonym. The other African Leucinodes species were unknown to science and are described as new: L. africensis sp. n., L. ethiopica sp. n., L. kenyensis sp. n., L. malawiensis sp. n., L. pseudorbonalis sp. n., L. rimavallis sp. n. and L. ugandensis sp. n. An identification key based on male genitalia is provided for the African Leucinodes species. Most imports of Leucinodes specimens from Africa into Europe refer to Leucinodes africensis, which has been frequently imported with fruits during the last 50 years. In contrast, L. laisalis has been much less frequently recorded, and L. pseudorbonalis as well as L. rimavallis only very recently in fruit imports from Uganda. Accordingly, interceptions of Leucinodes from Africa into other continents will need to be re-investigated for their species identity and will likely require, at least in parts, revisions of the quarantine regulations. The following African taxa are excluded from Leucinodes: Hyperanalyta Strand, 1918, syn. rev. as revised synonym of Analyta Lederer, 1863; Analyta apicalis (Hampson, 1896), comb. n. (Leucinodes); Lygropia aureomarginalis (Gaede, 1916), comb. n. (Leucinodes); Syllepte hemichionalis Mabille, 1900, comb. rev., S. hemichionalis idalis Viette, 1958, comb. rev. and S. vagans (Tutt, 1890), comb. n. (Aphytoceros). Deanolis iriocapna (Meyrick, 1938), comb. n. from Indonesia is originally described and misplaced in Sceliodes, and L. cordalis (Doubleday, 1843), comb. n. (Margaritia) from New Zealand, L. raondry (Viette, 1981), comb. n. (Daraba) from Madagascar as well as L. grisealis (Kenrick, 1912), comb. n. (Sceliodes) from New Guinea are transferred from Sceliodes to Leucinodes. While Leucinodes is now revised from Africa, it still needs further revision in Asia.
Data from: Species but not genotype diversity strongly impacts the establishment of rare colonisers
1. Understanding species coexistence and regulation of biodiversity are major research challenges, yet there is no consensus on the effects of diversity on diversity, including their mediation through plant–plant interactions. 2. We examined how the diversity of recipient communities impacted on the establishment of colonising species. We ran a greenhouse-based community experiment, creating artificial arable crop communities with varying levels of barley genotype and weed species diversity, analysed with structural equation modelling of responses across trophic levels. 3. Colonising arable weed species establishment was significantly reduced when the recipient communities' weed species richness, but not barley genotype richness, increased. Recipient plant communities with higher species richness occupied more total niche space and showed stronger competition with colonising species. In contrast, recipient plant communities with higher genotype richness, even though they had slightly greater niche space occupancy, had no significant effects on the colonisation of additional species. 4. Responses were species-specific: colonising common weed species establishment was less affected by the recipient plant communities than that of colonising rare weed species. Strong responses of colonising rare species were related to the abiotic rather than the biotic environment created by the recipient communities. The stronger response of colonising rare species suggests greater niche overlap with and competitive inferiority to the recipient plant community, whereas the relative independence of colonising common species indicates less niche overlap and/or competitive equality or superiority. 5. We observed a negative species diversity effect on colonising species, with the effect size increasing with increasing rarity of the colonising species. This differential responsiveness of colonising rare and common arable weed species to the presence of and diversity in the recipient arable plant communities may be crucial in understanding rarity and may result from differential evolutionary pathways in response to interactions.
Data from: Morphological, phylogenetic, and ecological diversity of the new model species Setaria viridis (Poaceae: Paniceae) and its close relatives
Premise of the study: Species limits of the emerging model organism Setaria viridis (tribe Paniceae, subtribe Cenchrinae) are not well defined. It is thought to be related to S. adhaerens, S. faberi, S. verticillata, and S. verticilliformis and in North America occurs with the morphologically similar S. pumila. An integrated approach was taken to evaluate its variation and relationships with the other taxa. Methods: Statistical morphology, flow cytometry, molecular phylogenetics, and growth experiments were employed to examine the group's physical variation, polyploidy, evolutionary relationships, and drought ecology, respectively. Key results: Setaria viridis contributed one genome to the tetraploids S. faberi, S. verticillata, and S. verticilliformis; the other genome of the latter two was contributed by S. adhaerens. Setaria pumila is unrelated. Morphologically, S. viridis is most similar to S. faberi, but all tested accessions of S. viridis were diploid, whereas those of S. faberi were all tetraploid. Principal component analysis of 70 morphological characters consistently separated S. viridis from S. faberi, largely by spikelet characters. The diagnostic morphological characters are not affected by watering. Setaria faberi is far more sensitive to drought, in terms of mortality and morphological stunting, than S. viridis or S. pumila. Conclusions: Setaria viridis is a diploid species and has contributed to several polyploid derivatives. The most morphologically similar of the polyploids is S. faberi, which differs in spikelet features, phylogenetics, genome size, and ecological response to drought. Researchers using field-collected S. viridis as a model organism will benefit from the clear delimitation provided in this study.
Data from: Bird assemblages on Amazonian river islands: patterns of species diversity and composition
The principles of island biogeography are rarely used to investigate the animal assemblages of Amazonian river islands. Here, we apply this approach to compare bird assemblages of Amazonian river islands with a variety of mainland habitats. We also examine how bird species diversity and composition are related to island physical attributes. Birds were sampled with mist nets and qualitative censuses on 11 river islands and at 24 mainland sites on the lower reaches of the Rio Negro in the Brazilian Amazon. Island bird assemblages are characterized by lower species richness and a higher abundance of a few dominant species. Additionally, species composition of the islands was significantly distinct from the mainland, including the nearby floodplain habitats. Number of bird species increased with island size and habitat diversity, and decreased with degree of isolation. In addition, small islands tended to harbour an impoverished subset of the species present on larger ones. Bird species diversity and composition on Amazonian river islands are likely influenced by the ecological succession and historical events affecting island formation. Considering their small total area across the Amazon basin, these insular fluvial environments could be disproportionally threatened by river channel disturbances such as climate change events, and hydroelectric building.
Data from: Compact cities or sprawling suburbs? optimising the distribution of people in cities to maximise species diversity
1. Conservation of biodiversity in urban environments depends on the responses of species to the intensity of urban development. 'Land sharing' and 'land sparing' represent alternate ends of a gradient that conceptualises a trade-off between the human population and biodiversity. We used a linear optimisation procedure to 1) identify the optimal allocation of land for people and nature, 2) assess whether the optimal allocation is more similar to land sparing or land sharing, and 3) examine how this might change under scenarios of human population growth. 2. We surveyed birds in 28 landscapes, each 25 ha in size, along a gradient of human population density (zero to ~1600 persons/25 ha) in the Greater Melbourne region, Australia. Species' responses to population density were estimated using generalised additive models (GAMs). These relationships were then used to determine the optimal allocation of land among different categories of population density based on maximising a community index, the geometric mean of relative abundance (G) of bird species. 3. Human population density was an important driver of the reporting rate for 28 species. Response curves differed among 'urban avoider', 'urban adapter' and 'urban exploiter' species. For the current human population in the study area, optimal allocation of land included elements of both land sharing and land sparing. However, for scenarios of increased population size, optimal allocation converged upon a land sparing design. 5. Synthesis and applications. Urban areas represent a mosaic of land uses that offer habitats of differing quality. Land sharing, based on sustaining biota amongst residential areas, performed poorly under all scenarios due to its inability to support species that depend on natural or semi-natural habitat. To sustain more than a homogenised avifauna in urban regions, large tracts of natural vegetation are needed within, or adjacent to, the urban environment. Protecting natural areas on urban fringes will be critical to the safeguarding of nature in the future as urban populations and land-use inevitably expand.
Data from: Maintaining genetic diversity and population panmixia through dispersal and not gene flow in a holocyclic heteroecious aphid species
Heteroecious holocyclic aphids exhibit both sexual and asexual reproduction and alternate among primary and secondary hosts. Most of these aphids can feed on several related hosts, and invasions to new habitats may limit the number of suitable hosts. For example, the aphid specialist Aphis glycines survives only on the primary host buckthorn (Rhamnus spp.) and the secondary host soybean (Glycine max) in North America where it is invasive. Owing to this specialization and sparse primary host distribution, host colonization events could be localized and involve founder effects, impacting genetic diversity, population structure and adaptation. We characterized changes in the genetic diversity and structure across time among A. glycines populations. Populations were sampled from secondary hosts twice in the same geographical location: once after secondary colonization (early season), and again immediately before primary host colonization (late season). We tested for evidence of founder effects and genetic isolation in early season populations, and whether or not late-season dispersal restored genetic diversity and reduced fragmentation. A total of 24 single-nucleotide polymorphisms and 6 microsatellites were used for population genetic statistics. We found significantly lower levels of genotypic diversity and more genetic isolation among early season collections, indicating secondary host colonization occurred locally and involved founder effects. Pairwise FST decreased from 0.046 to 0.017 in early and late collections, respectively, and while genetic relatedness significantly decreased with geographical distance in early season collections, no spatial structure was observed in late-season collections. Thus, late-season dispersal counteracts the secondary host colonization through homogenization and increases genetic diversity before primary host colonization.
Data from: Devario in Bangladesh: species diversity, sibling species, and introgression within danionin cyprinids (Teleostei: Cyprinidae: Danioninae)
Four species of Devario are recorded from Bangladesh: D. aequipinnatus, D. anomalus, D. coxi, new species, and D. devario. Devario aequipinnatus has a wide distribution in northern India and Bangladesh. Devario coxi, from southeastern Bangladesh near Cox's Bazar, differs from D. aequipinnatus in mtDNA (COI, p-distance 1.8%), colouration, proportional measurements, and meristics. The minor morphological differences and low frequency of overlapping meristics suggest relatively recent separation of D. coxi from other D. aequipinnatus. Devario anomalus occurs only in southeastern Bangladesh and is here reported from localities in addition to the type locality. It differs from the similar D. xyrops in adjacent Myanmar by slender body shape and by 2.3% p-distance in the COI gene. Specimens of D. anomalus from the Sangu River were found to have the mitochondrial genome of D. aequipinnatus from Bangladesh, but agree with other D. anomalus in the nuclear RAG1 gene. Devario devario has a wide distribution on the Indian Peninsula and border regions; in Bangladesh it is restricted in distribution to the Ganga, Brahmaputra, and Meghna drainages. Reports of D. assamensis and D. malabaricus from Bangladesh are misidentifications. Perilampus ostreographus M'Clelland, 1839, is tentatively synonymized with D. aequipinnatus. Phylogenetic analysis of 14 species of striped devarios based on the COI gene results in a polytomy with four unresolved clades. Devario deruptotalea from the Chindwin basin is the sister group of D. aequipinnatus+D. coxi. Devario devario is the sistergroup of D. xyrops+D. anomalus.
Data from: Wild boar (Sus scrofa) increases species diversity of semi-dry grassland: field experiment with simulated soil disturbances
Background Foraging activities of wild boar (Sus scrofa) create small-scale soil disturbances in many different vegetation types. Rooting alters species composition by opening niches for less-competitive plants and as a recurrent factor becomes a part of the community disturbance regime. Vegetation responses to wild boar disturbance have mostly been studied in the boar's non-native range or in native forest, rather than in open habitats in the native range. We investigate the response of open European semi-dry grassland vegetation dominated by (Brachypodium pinnatum) to native wild boar pressure in an abandoned agricultural landscape. Methods To describe the disturbance regime, we repeatedly mapped rooted patches during a 5-year period. Additionally, to study the vegetation response, we performed an artificial disturbance experiment by creating 30 pairs of simulated disturbances and undisturbed plots. The vegetation composition of the paired plots was repeatedly sampled five times in eight years of the study. Results Based on repeated mapping of disturbances, we predict that if the disturbance regime we observed during the 5-year period were maintained over the long term, it would yield a stable vegetation ratio consisting of 98.7 % of the grassland undisturbed, 0.4 % with fresh disturbance and 0.9 % in older successional stages. Vegetation composition on the artificially disturbed plots was continuously converging to that of undisturbed vegetation, but these disturbed plots still differed significantly in composition and had higher species number, even after eight years of succession. Synthesis Our results thus show that wild boar disturbance regime in its native range increases heterogeneity and species diversity of semi-dry grassland vegetation.
Data from: Deciphering the drivers of negative species-genetic diversity correlation in Alpine amphibians
The evolutionary and ecological importance of neutral and adaptive genetic diversity is widely recognized. Nevertheless, genetic diversity is rarely assessed for conservation planning, which often implicitly assumes a positive correlation between species and genetic diversity. Multiple drivers can cause the co-variation between the genetic diversity of one species and the richness of the whole communities, and explicit tests are needed to identify the processes that can determine species-genetic diversity correlations (SGDC). Here we tested whether intrapopulation genetic diversity (at neutral loci) and species richness co-vary in the amphibian communities of a southern Alpine region (Trentino, Italy), using the common frog (Rana temporaria) as focal species for the study of genetic diversity. We also analyzed ecological similarity, niche overlap and interspecific interactions between the species, to unravel the processes determining SGDC. The neutral genetic diversity of common frogs was negatively related to species richness. The negative SGDC was probably due to an opposite influence of environmental gradients on the two levels of biodiversity, since the focal species and the other amphibians differ in ecological preferences, particularly in terms of thermal optimum. Conversely, we did not find evidence for a role of interspecific interactions in the negative SGDC. Our findings stress that species richness cannot be used as a universal proxy for genetic diversity, and only combining SGDC with analyses on the determinants of biodiversity can allow to identify the processes determining the relationships between genetic and species diversity.
Data from: Diversity in tropical ecosystems: the species richness and turnover of moths in Malaysian rainforests
As a contribution to accurate estimation of arthropod alpha and beta diversities in tropical forests, we present results of some of the largest moth samples ever collected in the Malaysian region. To estimate alpha diversity, light traps were run at three geographically distinct locations. We generated individual-based and coverage-based rarefaction curves to estimate sampling sufficiency and alpha diversity of the locations. Despite a large number of moths collected (67 282 individuals, from three locations), none of the rarefaction curves reached asymptote. The species accumulation curves based on the Chao1 richness estimator at each location suggested that, even when sampling yielded over 30 000 individuals, Chao1 could not reliably estimate the observed number of species. In one of the three locations, moths were collected systematically by light traps in 1979–1980 and 2000–2001. Despite over 160 trapping nights and 16 500 individuals collected in total, the estimated total number of species (2262) was well below the general collection conducted at the same location over a 35-year period [3921 species (1975–2013)]. Beta diversity was investigated using the samples collected at one location on two occasions over a 20-year period. The faunal composition has changed over the 20-year period, possibly as a result of extensive land-use change around the study location. We estimated the minimum sampling effort required to detect such changes by calculating type II errors. Unlike alpha diversity estimation, we found that only four replicate samples, each with only two trapping nights, would be sufficient to reliably detect changes in assemblage composition.
Data from: Breeding bird species diversity across gradients of land use from forest to agriculture in Europe
Loss, fragmentation and decreasing quality of habitats have been proposed as major threats to biodiversity world-wide, but relatively little is known about biodiversity responses to multiple pressures, particularly at very large spatial scales. We evaluated the relative contributions of four landscape variables (habitat cover, diversity, fragmentation and productivity) in determining different components of avian diversity across Europe. We sampled breeding birds in multiple 1-km2 landscapes, from high forest cover to intensive agricultural land, in eight countries during 2001−02. We predicted that the total diversity would peak at intermediate levels of forest cover and fragmentation, and respond positively to increasing habitat diversity and productivity; forest and open-habitat specialists would show threshold conditions along gradients of forest cover and fragmentation, and respond positively to increasing habitat diversity and productivity; resident species would be more strongly impacted by forest cover and fragmentation than migratory species; and generalists and urban species would show weak responses. Measures of total diversity did not peak at intermediate levels of forest cover or fragmentation. Rarefaction-standardized species richness decreased marginally and linearly with increasing forest cover and increased non-linearly with productivity, whereas all measures increased linearly with increasing fragmentation and landscape diversity. Forest and open-habitat specialists responded approximately linearly to forest cover and also weakly to habitat diversity, fragmentation and productivity. Generalists and urban species responded weakly to the landscape variables, but some groups responded non-linearly to productivity and marginally to habitat diversity. Resident species were not consistently more sensitive than migratory species to any of the landscape variables. These findings are relevant to landscapes with relatively long histories of human land-use, and they highlight that habitat loss, fragmentation and habitat-type diversity must all be considered in land-use planning and landscape modeling of avian communities.
Data from: A multispecies approach reveals hot-spots and cold-spots of diversity and connectivity in invertebrate species with contrasting dispersal modes
Genetic diversity is crucial for species' maintenance and persistence, yet is often overlooked in conservation studies. Species diversity is more often reported due to practical constraints, but it is unknown if these measures of diversity are correlated. In marine invertebrates, adults are often sessile or sedentary and populations exchange genes via dispersal of gametes and larvae. Species with a larval period are expected to have more connected populations than those without larval dispersal. We assessed the relationship between measures of species and genetic diversity, and between dispersal ability and connectivity. We compiled data on genetic patterns and life history traits in nine species across five phyla. Sampling sites spanned 600 km in the northwest Mediterranean Sea and focused on a 50 km area near Marseilles, France. Comparative population genetic approaches yielded three main results. (1) Species without larvae showed higher levels of genetic structure than species with free-living larvae but the role of larval type (lecithotrophic or planktotrophic) was negligible. (2) A narrow area around Marseilles, subject to offshore advection, limited genetic connectivity in most species. (3) We identified sites with significant positive contributions to overall genetic diversity across all species, corresponding with areas near low human population densities. In contrast, high levels of human activity corresponded with a negative contribution to overall genetic diversity. Genetic diversity within species was positively and significantly linearly related with local species diversity. Our study suggests that local contribution to overall genetic diversity should be taken into account for future conservation strategies.
Data from: Species richness and patterns of overdispersion, clustering and randomness shape phylogenetic and functional diversity-area relationships in habitat islands
<p><b>Aim:</b> To evaluate how the area of habitat island systems influences multiple facets of diversity. </p> <p><b>Location:</b> Southern Brazil. </p> <p><b>Taxon:</b> Birds. </p> <p><b>Methods:</b> Using an Information Theoretic approach, we compared the fit of 20 diversity–area relationship (DARs) models in three habitat island systems. We tested for the best-fit model, model-family, shape, and presence/absence of an asymptote. We used species richness (SR), Faith's phylogenetic diversity (PD) and Faith's functional diversity (FD) to assess species–area (SARs), phylogenetic (PDARs) and functional diversity–area relationships (FDARs). We controlled for the effect of SR in PD and FD via null models to assess PDARs and FDARs independently of SR and to explore the influence of phylogenetic and functional randomness, clustering and overdispersion. </p> <p><b>Results:</b> PDARs and FDARs built with PD and FD resembled SARs and were all best fitted by convex or sigmoidal, upwards oriented, non-asymptotic models. Controlling for SR in diversity indices produced flat or downwards-oriented, weak PDARs and FDARs, which were best fitted by convex, non-asymptotic models or the linear model. Taxonomic diversity accumulated faster with area than functional diversity, which accumulated faster than phylogenetic diversity. Randomness and clustering patterns prevailed in shaping PDARs and FDARs relative to overdispersion. </p> <p><b>Main conclusions: </b>Controlling for SR in PD and FD affects DARs patterns and the strength of the relationships. Irrespective of this influence of SR, a few simple models of the power and exponential model-families best fit DARs. Model parameters reveal differences in the response of each facet of diversity to increases in area, highlighting the complementary nature of DARs. When considered independently of SR, both PDAR and FDAR patterns largely reflect the broad variation of phylogenetic and functional diversity in small islands. It is therefore likely that the ecological processes that promote phylogenetic and functional overdispersion and clustering operate at contrasting spatial scales.</p>
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: Diversity, phylogeny and biogeography of the South American 'cardiomyine' rodents (Hystricognathi, Cavioidea) with a description of two new species
'Cardiomyine' rodents are extinct large terrestrial Caviidae closely related to capybaras, that inhabited large parts of South America during the middle Miocene and Pliocene. They are mostly preserved as isolated teeth, but also as skull and jaw fragments. Here we revise the taxonomy of this group and describe two new species, each pertaining to one of the two main late Miocene groups, represented by the genera Caviodon and Cardiomys. This suggests that the diversity of 'cardiomyines' was higher than previously thought. Among the specimens studied there are two almost complete skulls; one from the Andalhuala Formation, Catamarca, and the other from the Arroyo Chasicó Formation, Buenos Aires. The first, housed in the Field Museum of Natural History, was originally catalogued as Cardiomys ameghinorum, a common species for the late Miocene of north-western Argentina (NOA), but is here transferred to the genus Caviodon. This is the first mention of the genus for NOA, enlarging its geographical distribution for the late Miocene. The second skull, assigned to Cardiomys sp., is housed in the Museo de La Plata. Furthermore, from the revision of the holotypes of the species of Caviodon (C. multiplicatus, C. bravardi, C. (Lelongia) paranensis, C. angustidens and C. scalai from the Conglomerado osífero of the Ituzaingó Formation; late Miocene, Argentina) we propose their synonymy with the type species C. multiplicatus, decreasing the specific diversity in that locality. Finally, our phylogenetic analysis indicates that the species of 'cardiomyines' are paraphyletic, placing them in a basal position among the Hydrochoerinae.
Data from: Bottom-up effects of host-plant species diversity and top-down effects of ants interactively increase plant performance
While plant diversity is well known to increase primary productivity, whether these bottom-up effects are enhanced by reciprocal top-down effects from the third trophic level is unknown. We studied whether pine tree species diversity, aphid-tending ants and their interaction determined plant performance and arthropod community structure. Plant diversity had a positive effect on aphids, but only in the presence of mutualistic ants, leading to threefold greater number of both groups in the tri-specific cultures than in monocultures. Plant diversity increased ant abundance not only by increasing aphid number, but also by increasing ant recruitment per aphid. The positive effect of diversity on ants in turn cascaded down to increase plant performance; diversity increased plant growth (but not biomass), and this effect was stronger in the presence of ants. Consequently, bottom-up effects of diversity within the same genus and guild of plants and top-down effects from the third trophic level (predatory ants) interactively increased plant performance.
Data from: Niche construction by growth forms is as strong a predictor of species diversity as environmental gradients
We present a conceptual framework that describes how species belonging to a growth form collectively can be niche constructors (i.e. modify niches) and affect species diversity in plant communities. We use an empirical assessment of tundra plant communities to illustrate the framework's utility. In doing so, we make a first investigation of collective niche construction in ecological communities. In tundra plant communities, growth forms differently affect ecosystem process rates and cause environmental modifications; thus, growth forms are strong candidates for being niche constructors. To assess the impact of growth form niche construction on plant species diversity, we excluded the species of the growth form applied as niche constructor when estimating the community species diversity. We assessed niche construction in 70 tundra meadow communities and 1450 randomly selected tundra plant communities that are distributed along ecological gradients in temperature, resource availability, competitive interference and herbivory. These gradients allowed us to concomitantly assess to what extent the niche construction is independent of environmental conditions. Growth forms varied from strong positive to neutral predictors of both species richness and Simpson index in the order of forbs, grasses, sedges, deciduous shrubs and evergreen shrubs, suggesting that growth forms have important roles as niche constructors in tundra plant communities. Also, the environmental conditions were strong predictors of species diversity, but they did not interact with or confound the effects of growth forms. Forbs and grasses were the least abundant growth forms, yet they were the strongest positive predictors of species diversity. Therefore, our results suggest a particular niche-constructing role of these growth forms for enhancing species diversity in tundra plant communities. Synthesis. In this study, we provide conceptual and empirical evidence for collective niche construction as a powerful ecological process that affects species diversity and that can act independently of environmental conditions. Species sharing a single trait or species belonging to a growth form can act as collective niche constructors, and as exemplified for growth forms in this study, be important predictors of species diversity in ecological communities.
Data from: AFLP diversity and spatial structure of Calycophyllum candidissimum (Rubiaceae), a dominant tree species of Nicaragua's critically endangered seasonally dry forest
The Central American seasonally dry tropical (SDT) forest biome is one of the worlds' most endangered ecosystems, yet little is known about the genetic consequences of its recent fragmentation. A prominent constituent of this biome is Calycophyllum candidissimum, an insect-pollinated and wind-dispersed canopy tree of high socio-economic importance, particularly in Nicaragua. Here, we surveyed amplified fragment length polymorphisms across 13 populations of this species in Nicaragua to elucidate the relative roles of contemporary vs historical factors in shaping its genetic variation. Genetic diversity was low in all investigated populations (mean HE=0.125), and negatively correlated with latitude. Overall population differentiation was moderate (ΦST=0.109, P<0.001), and Bayesian analysis of population structure revealed two major latitudinal clusters (I: 'Pacific North'+'Central Highland'; II: 'Pacific South'), along with a genetic cline between I and II. Population-based cluster analyses indicated a strong pattern of 'isolation by distance' as confirmed by Mantel's test. Our results suggest that (1) the low genetic diversity of these populations reflects biogeographic/population history (colonisation from South America, Pleistocene range contractions) rather than recent human impact; whereas (2) the underlying process of their isolation by distance pattern, which is best explained by 'isolation by dispersal limitation', implies contemporary gene flow between neighbouring populations as likely facilitated by the species' efficient seed dispersal capacity. Overall, these results underscore that even tree species from highly decimated forest regions may be genetically resilient to habitat fragmentation due to species-typical dispersal characteristics, the necessity of broad-scale measures for their conservation notwithstanding.
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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.