Find research datasets worth reusing

opencc-zeroOct 2020View details →

Data from: Climatic drivers of latitudinal variation in Late Triassic tetrapod diversity

The latitudinal biodiversity gradient (LBG), the increase in biodiversity from the poles to the equator, is one of the most widely recognised global macroecological patterns, yet its deep time evolution and drivers remain uncertain. The Late Triassic (237–201 million years ago), a critical interval for the early evolution and radiation of modern tetrapod groups (e.g. crocodylomorphs, dinosaurs, mammaliamorphs), offers a unique opportunity to explore the palaeolatitudinal patterns of tetrapod diversity since it is extensively sampled spatially when compared with other pre-Cenozoic intervals, particularly at lower palaeolatitudes. Here, we explore palaeolatitudinal patterns of Late Triassic tetrapod diversity by applying sampling standardisation to comprehensive occurrence data from the Paleobiology Database. We then use palaeoclimatic model simulations to explore the palaeoclimatic ranges occupied by major tetrapod groups, allowing insight into the influence of palaeoclimate on the palaeolatitudinal distribution of these groups. Our results show that Late Triassic tetrapods generally do not conform to a modern-type LBG; instead, sampling-standardised species richness is highest at mid-palaeolatitudes. In contrast, the richness of pseudosuchians (crocodylians and their relatives) is highest at the palaeoequator, a pattern that is retained throughout their subsequent evolutionary history. Pseudosuchians generally occupied a more restricted range of palaeoclimatic conditions than other tetrapod groups, a condition analogous to modern day reptilian ectotherms, while avemetatarsalians (the archosaur group containing dinosaurs and pterosaurs) exhibit comparatively wider ranges, which is more similar to modern endotherms, such as birds and mammals, suggesting important implications for the evolution of thermal physiology in dinosaurs.

opencc-zeroOct 2023View details →

Climate-associated variation in the drivers of benthic macroinvertebrate species-area relationships across shallow freshwater lakes

The island species-area relationship (ISAR) describes how species richness increases with increasing area of a given island or island-like habitat, such as freshwater lakes. While the ISAR is one of the most common phenomena observed in ecology, there is variation in both the form of the relationship and its underlying mechanisms. We compiled a global dataset of benthic macroinvertebrates from 524 shallow freshwater lakes, ranging from 1 to 293300 ha in area. We used individual-based rarefaction to determine the degree to which ISAR was influenced by mechanisms other than passive sampling (larger islands passively sample more individuals from the regional pool and, therefore, have more species than smaller islands), which would bias results away from expected relationships between rarefied species richness (and other measures that capture relative abundances) and lake area. We also examined how climate may alter the shape of the ISARs. We found that both rarefied species richness (the number of species standardized by area or number of individuals) and a measure of evenness emphasizing common species exhibit non-significant relationships with lake area, suggesting that the expected ISARs in these lakes most likely result from passive sampling. While there was considerable variation among ISARs across the investigated lakes, we found an overall positive rarefied ISAR for lakes in warm (i.e., tropical/subtropical) regions (n = 195), and in contrast, an overall negative rarefied ISAR in cool (i.e., north temperate) lakes (n = 329). This suggested that mechanisms beyond passive sampling (e.g., colonization-extinction dynamics and/or heterogeneity) were more likely to operate in warm lakes. One possible reason for this difference is that the area-dependent intensity of fish predation, which can lead to flatter ISARs, is weaker in warmer relative to cooler lakes. Our study illustrates the importance of understanding both the pattern and potential processes underlying the ISARs of freshwater lakes in different climatic regions. Further, it provides a baseline for understanding how further changes to the ecosystem (i.e., in lake area or climate) might influence biodiversity patterns.

opencc-zeroNov 2023View details →

Data from: Climatic damage cause variations of agricultural insurance loss for the Pacific Northwest region of the United States

Agricultural crop insurance is an important component for mitigating farm risk, particularly given the potential for unexpected climatic events. Using a 2.8 million nationwide insurance claim dataset from the United States Department of Agriculture (USDA), this research study examines spatiotemporal variations of over 31,000 agricultural insurance loss claims across the 24-county region of the inland Pacific Northwest (iPNW) portion of the United States, from 2001 to 2022. Wheat is the dominant insurance loss crop for the region, accounting for over 2.8 billion dollars in indemnities, with over 1.5 billion dollars resulting in claims due to drought (across the 22 year time period). While fruit production generates considerably lesser insurance losses (400 million dollars) as a primary result of freeze, frost, and hail, overall revenue ranks number one for the region, with 2 billion dollars in sales, across the same time range. Principal components analysis of crop insurance claims showed distinct spatial and temporal differentiation in wheat and apple insurance losses using the range of damage causes as factor loadings. The first two factor loadings for wheat accounts for approximately 50 percent of total variance for the region, while a separate analysis of apples accounts for over 60 percent of total variance. These distinct orthogonal differences in losses by year and commodity in relationship to damage causes suggest that insurance loss analysis may serve as an effective barometer in gauging climatic influences.

opencc-zeroDec 2023View details →

Machine learning reveals that climate, geography, and cultural drift all predict bird song variation in coastal Zonotrichia leucophrys

Previous work has demonstrated that there is extensive variation in the songs of White-crowned Sparrow (Zonotrichia leucophrys) throughout the species range, including between neighboring (and genetically distinct) subspecies Z. l. nuttalli and Z. l. pugetensis. Using a machine learning approach to bioacoustic analysis, we demonstrate that variation in song is correlated with year of recording (representing cultural drift), geographic distance, and climatic differences, but the response is subspecies- and season-specific. Automated machine learning methods of bird song annotation can process large datasets more efficiently, allowing us to examine 1,913 recordings across ~60 years. We utilize a recently published artificial neural network to automatically annotate White-crowned Sparrow vocalizations. By analyzing differences in syllable usage and composition, we recapitulate the known pattern where Z. l. nuttalli and Z. l. pugetensis have significantly different songs. Our results are consistent with the interpretation that these differences are caused by the changes in characteristics of syllables in the White-crowned Sparrow repertoire. This supports the hypothesis that the evolution of vocalization behavior is affected by the environment, in addition to population structure.

opencc-by-4.0Dec 2023View details →

Dataset for: Climate and shared evolutionary history drive trait variation among species of Neotropical understory monocots

Dataset and p-values form phylogenetically generalized least square models accompanying the manuscript "Climate and shared evolutionary history drive trait variation among species of Neotropical understory monocots".

opencc-zeroJan 2024View details →

Data from: A species' response to spatial climatic variation does not predict its response to climate change

The dominant paradigm for assessing ecological responses to climate change assumes that future states of individuals and populations can be predicted by current, species-wide performance variation across spatial climatic gradients. However, if the fates of ecological systems are better predicted by past responses to in situ climatic variation through time, this current analytical paradigm may be severely misleading. Empirically testing whether spatial or temporal climate responses better predict how species respond to climate change has been elusive, largely due to restrictive data requirements. Here we leverage a newly collected network of ponderosa pine tree-ring time series to test whether statistically inferred responses to spatial versus temporal climatic variation better predict how trees have responded to recent climate change. When compared to observed tree growth responses to climate change since 1980, predictions derived from spatial climatic variation were wrong in both magnitude and direction. This was not the case for predictions derived from climatic variation through time, which were able to replicate observed responses well. Future climate scenarios through the end of the 21st century exacerbated these disparities. These results suggest that the currently dominant paradigm of forecasting the ecological impacts of climate change based on spatial climatic variation may be severely misleading over decadal to centennial timescales.

opencc-by-4.0Nov 2023View details →

Climate warming and temporal variation in reproduction strategies in the endangered meadow viper

Here, we used more than three decades of mark-recapture data in a natural population of the endangered meadow viper (Vipera ursinii ursinii) to unravel the patterns of temporal variation in reproductive traits, local climatic determinants of inter-annual variation in reproduction and the potential buffering effects of life cycle on population growth rate. We found significant inter-annual variation in annual body growth, gestation length, post-parturition body condition, clutch success and offspring traits at birth, but little temporal effects in reproductive effort. Temperature during gestation was the most influential local climatic determinant by shortening gestation length, and increasing clutch success and post-parturition body condition. Neither air humidity nor insolation was found to influence reproduction.

opencc-by-4.0Mar 2022View details →

Data for the Manuscript 'Phenotypic Variation from Waterlogging in Multiple Perennial Ryegrass Varieties under Climate Change Conditions'

Experimental data supporting the findings of the manuscript 'Phenotypic Variation from Waterlogging in Multiple Perennial Ryegrass Varieties under Climate Change Conditions'. This dataset will be made publicly available when the manuscript has been accepted for journal publication unless exceptional conditions become apparent.

opencc-by-4.0Nov 1978View details →

Long-term variations of daily insolation and Quaternary climatic changes

Supplementary material to: Berger A. L. (1978), Long-term variations of daily insolation and Quaternary climatic changes, Journal of the Atmospheric Sciences, (35) 2362-2367 doi:10.1175/1520-0469(1978)035<2362:LTVODI>2.0.CO;2 Tables and FORTRAN computer code for the computation of daily mean insolation, according to the solution BER78. This solution is commonly referred to as BER78. Material uploaded to Zenodo by Michel Crucifix on 2022-10-14.

opencc-zeroOct 2022View details →

Limited movement of an avian hybrid zone in relation to regional variation in magnitude of climate change

Studies of natural hybrid zones can provide documentation of range shifts in response to climate change and identify loci important to reproductive isolation. Using a temporal (36–38 years) comparison of the black-capped (Poecile atricapillus) and Carolina (P. carolinensis) chickadee hybrid zone, we investigated movement of the western portion of the zone (western Missouri) and assessed whether loci and pathways underpinning reproductive isolation were similar to those in the eastern portion of the hybrid zone. Using 92 birds sampled along the hybrid zone transect in 2016 and 68 birds sampled between 1978 and 1980, we generated 11,669 SNPs via ddRADseq. These SNPs were used to assess movement of the hybrid zone through time and to evaluate variation in introgression among loci. We demonstrate that the interface has moved ~5 km to the northwest over the last 36–38 years, i.e., at only one-fifth the rate at which the eastern portion (e.g., Pennsylvania, Ohio) of the hybrid zone has moved. Temperature trends over the last 38 years reveal that eastern areas have warmed 50% more than western areas in terms of annual mean temperature, possibly providing an explanation for the slower movement of the hybrid zone in Missouri. Our results suggest hybrid zone movement in broadly distributed species, such as chickadees, will vary between areas in response to local differences in the impacts of climate change.

opencc-by-4.0Mar 2019View details →

Data from: Hydrology induces intraspecific variation in freshwater fish morphology under contemporary and future climate scenarios

Datasets for manuscript "Andres, K. J., Chien, H., and Knouft, J. H. Hydrology induces intraspecific variation in freshwater fish morphology under contemporary and future climate scenarios. Science of the Total Environment. <a href="https://doi.org/10.1016/j.scitotenv.2019.03.292">https://doi.org/10.1016/j.scitotenv.2019.03.292</a>" landmarks.zip: landmarks digitized on images of 1081 specimens using TpsDig2 software. streamflow_estimates.csv: Contemporary (1980-2009) and future (2070-2099) streamflow estimates [avg: average annual streamflow discharge (m3 s-1); cv: coefficient of variation of annual discharge] in sub-basins containing populations of 6 minnow species in IL, USA

opencc-by-4.0Dec 2015View details →

Figure 1. A map showing the three climatic regions from which the 162 in Patterns of skull variation in relation to some geoclimatic conditions in the greater jerboa Jaculus orientalis (Rodentia, Dipodidae) from Tunisia

Figure 1. A map showing the three climatic regions from which the 162 samples of Jaculus orientalis were collected in Tunisia, with isohyets indicating the average annual rainfall measured in millimeters (mm year–1). Main climates: B- arid, C- warm temperate. Precipitation: W- desert, S- steppe, s- summer dry. Temperature: a- hot summer, h- hot arid.

Fig. 3 in A snapshot of climate drivers and temporal variation of Ixodes ovatus abundance from a giant panda living in the wild

Fig. 3. Boxplot of tick abundance, female-to-male ratio and important climate factors change by months. A: Tick daily abundance; B: Daily female-to-male ratio of ticks; C: Daily temperature; D: Daily air pressure. Variables sharing the same letters among months were not significantly different. The five-day-rolling average values were calculated for all the variables that change by months.

Fig. 6 in A snapshot of climate drivers and temporal variation of Ixodes ovatus abundance from a giant panda living in the wild

Fig. 6. Daily average tick abundance, daily average air pressure and daily average temperature with standard deviations by months. All the values are calculated with five-day-rolling average values.

Fig. 2. Ixodes. ovatus collected from the giant panda. A in A snapshot of climate drivers and temporal variation of Ixodes ovatus abundance from a giant panda living in the wild

Fig. 2. Ixodes. ovatus collected from the giant panda. A: Dorsal of the adult female I. ovatus; B: Ventral of the adult female I. ovatus; C: Dorsal of the adult male I. ovatus; D: Ventral of the adult male I. ovatus.

Fig. 5 in A snapshot of climate drivers and temporal variation of Ixodes ovatus abundance from a giant panda living in the wild

Fig. 5. The correlation plot of daily tick abundance and the daily air pressure with trending line. The five-day-rolling average values were calculated for tick abundance and the air pressure.