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List of genera
No full textNames of the genera corresponding to the numbers that appear in the occupancy-rank plots depicted in figure 4
Data from: Recent grazing reduces reptile richness but historic grazing filters reptiles based on their functional traits
No full text1. Grazing by mammalian herbivores can alter vegetation structure and composition. It can therefore affect critical habitat features used by native wildlife for shelter, feeding and breeding. This can have variable effects, which advantage or disadvantage particular species, depending on habitat requirements. 2. We tested the relative effects of recent and historic livestock grazing and recent rabbit and kangaroo grazing on all reptiles, and on specific groups of reptiles based on three functional traits: habitat preference (semi-arboreal, terrestrial, fossorial), activity pattern (diurnal, nocturnal) and primary foraging habitat (tree, litter, open). 3. We used structural equation modelling to assess the direct and indirect impacts of mammalian herbivores (livestock, and free-ranging kangaroos and rabbits) on reptile richness at 108 semi-arid woodland sites in eastern Australia. We used a trait-based approach to classify reptiles according to their: (1) habitat preference, (2) activity pattern and, (3) foraging preference. 4. We recorded 42 reptile species from 1736 specimens caught over 13,824 trap nights. Sites grazed by rabbits were associated with greater richness of semi-arboreal species. Kangaroo grazing had virtually no effects on total richness or richness within trait groups. The effects of recent and historic livestock grazing differed among reptile trait groups. Increasing intensity of recent livestock grazing reduced the richness of most reptile groups directly, and indirectly suppressed the positive effect of native plant richness on reptile richness. The effects of historic livestock grazing, however, filtered reptiles based on their traits, reducing the richness of tree-shrub foraging reptiles only. Increasing woody cover had direct suppressive effects on all reptiles, but particularly open foragers and terrestrial species. Overall, the effects of recent livestock grazing were stronger than those of plant richness or woody cover. 5. Synthesis and applications. We therefore demonstrate how grazing by all herbivores, both domestic and free-ranging, needs to be managed according to seasonal conditions in order to meet the conservation needs of semi-arid reptiles within landscapes dominated by livestock
Data from: Supplementary stocking selects for domesticated genotypes
No full textStocking of hatchery produced fish is common practise to mitigate declines in natural populations and may have unwanted genetic consequences. Here we describe a novel phenomenon arising where broodstock used for stocking may be introgressed with farmed individuals. We test how stocking affects introgression in a wild population of Atlantic salmon (Salmo salar) by quantifying how the number of adult offspring recaptured in a stocked river depend on parental introgression. We found that hatchery conditions favour farmed genotypes such that introgressed broodstock produce up to four times the number of adult offspring compared to non-introgressed broodstock, leading to increased introgression in the recipient spawning population. Our results provide the first empirical evidence that stocking can unintentionally favour introgressed individuals and through selection for domesticated genotypes compromise the fitness of stocked wild populations
Data from: A small yet occasional meal: predatory drill holes in Paleocene ostracods from Argentina and methods to infer predation intensity
No full textOstracods are common yet understudied prey in the fossil record. We document drill holes in Paleocene (Danian) ostracods from central Argentina using 9025 specimens representing 66 species. While the assemblage-level drilling percentage is only 2.3%, considerable variation exists within species (0.3–25%), suggesting prey preference by the drillers. This preference is not determined by abundance because no significant correlation is found between species abundance and drilling percentages. Seven methods were used, some of which are new, to quantify drilling percentages for the abundant and commonly drilled Togoina argentinensis. The obtained range from 9.9 to 14.6% suggests that drilling percentages are fairly insensitive to the method used, implying that comparisons across studies appear possible. Using this knowledge, the Cretaceous-Paleogene mass extinction had limited effect on drilling intensity in ostracod prey. The cylindrical (Oichnus simplex) and parabolic (O. paraboloides) drill holes from Argentina may have been primarily caused by muricid and naticid gastropods. Two oval drill holes (O. ovalis) are morphologically similar to octopod drill holes, but their small size, the fact that extant octopods are unknown to drill ostracods and the absence of such holes in co-occurring gastropods preclude ascription to a predator. Drill holes are located preferentially in the median and dorsal regions, where most soft tissue including the adductor muscle is located. Drilled specimens are statistically taller than non-drilled specimens for T. argentinensis and larger predators selected larger ostracods. The drilling percentage is significantly higher in ornamented ostracods, suggesting that ornamentation is not functional against drilling predators here
Valve size measurements of drilled and not drilled on Togoina argentinensis from the Danian of Argentina.
No full textThe valve size measurements on Togoina argentinensis (drilled and not drilled specimens) from the Danian (Roca and Jagüel formations) of Argentina and the type of valve found are indicated
Structure input file for E. sp. 3.
No full textA Structure data file consisting of 20 E. sp. 3 samples genotyped at 604 loci. See README file for MAINPARAMS and EXTRAPARAMS settings
Data from: Large birds travel farther in homogeneous environments
No full textAim: Animal movement is an important determinant of individual survival, population dynamics, and ecosystem structure and function. Yet it is still unclear how local movements are related to resource availability and the spatial arrangement of resources. Using resident bird species and migratory bird species outside of the migratory period, we examined how the distribution of resources affect the movement patterns of both large terrestrial birds (e.g., raptors, bustards, hornbills) and waterbirds (e.g., cranes, storks, ducks, geese, flamingos). Location: Global Time Period: 2003 - 2015 Major taxa studied: Birds Methods: We compiled GPS tracking data for 386 individuals across 36 bird species. We calculated the straight-line distance between GPS locations of each individual at the 1-hour and 10-day timescales. For each individual and timescale, we calculated the median and 0.95 quantile of displacement. We used linear mixed-effects models to examine the effect of the spatial arrangement of resources, measured as Enhanced Vegetation Index (EVI) homogeneity, on avian movements while accounting for mean resource availability, body mass, diet, flight type, migratory status and taxonomy and spatial autocorrelation. Results: We found a significant effect of resource spatial arrangement at the 1-hour and 10-day timescales. On average, individual movements were seven times longer in environments with homogeneously distributed resources compared with areas of low resource homogeneity. Contrary to previous work, we found no significant effect of resource availability, diet, flight type, migratory status or body mass on the non-migratory movements of birds. Main conclusions: We suggest that longer movements in homogeneous environments may reflect the need for different habitat types associated with foraging and reproduction. This highlights the importance of landscape complementarity, where habitat patches within a landscape include a range of different, yet complimentary resources. As habitat homogenisation increases, it may force birds to travel increasingly longer distances to meet their diverse needs
Data from: Variation of carbon contents in eelgrass (Zostera marina) sediments implied from depth profiles
No full textSeagrass meadows are able to store significant amounts of organic carbon in their underlying sediment but global estimates are uncertain partly due to spatiotemporal heterogeneity between areas and species. In order to provide robust estimates, there is a need to better understand the fate of, and mechanisms behind, organic carbon storage. In this observational study, we analyse a suite of biotic and abiotic parameters in sediment cores from 47 different eelgrass (Zostera marina) beds spanning the distributional range of the Northern Hemisphere. Depth profiles revealed three patterns of vertical distribution where POC either increased, decreased, or showed no distinct pattern with sediment depth. These categories exhibited distinct profiles of δ13C and C:N ratios, where high POC profiles had a proportionally larger storage of eelgrass-derived material whereas low POC profiles were dominated by phytoplanktonic and macroalgal material. However, high POC did not always translate into high carbon density. Along with better constrained sedimentation rates, these results can ultimately contribute to our understanding of carbon content in seagrass beds