14 research outputs found
Prelude to the Anthropocene: Two new North American Land Mammal Ages (NALMAs)
Human impacts have left and are leaving distinctive imprints in the geological record. Here we show that in North America, the human-caused changes evident in the mammalian fossil record since c. 14,000 years ago are as pronounced as earlier faunal changes that subdivide Cenozoic epochs into the North American Land Mammal Ages (NALMAs). Accordingly, we define two new North American Land Mammal Ages, the Santarosean and the Saintagustinean, which subdivide Holocene time and complete a biochronologic system that has proven extremely useful in dating terrestrial deposits and in revealing major features of faunal change through the past 66 million years. The new NALMAs highlight human-induced changes to the Earth system, and inform the debate on whether or not defining an Anthropocene epoch is justified, and if so, when it began
Life history, climate and biogeography interactively affect worldwide genetic diversity of plant and animal populations.
Understanding how biological and environmental factors interactively shape the global distribution of plant and animal genetic diversity is fundamental to biodiversity conservation. Genetic diversity measured in local populations (GDP) is correspondingly assumed representative for population fitness and eco-evolutionary dynamics. For 8356 populations across the globe, we report that plants systematically display much lower GDP than animals, and that life history traits shape GDP patterns both directly (animal longevity and size), and indirectly by mediating core-periphery patterns (animal fecundity and plant dispersal). Particularly in some plant groups, peripheral populations can sustain similar GDP as core populations, emphasizing their potential conservation value. We further find surprisingly weak support for general latitudinal GDP trends. Finally, contemporary rather than past climate contributes to the spatial distribution of GDP, suggesting that contemporary environmental changes affect global patterns of GDP. Our findings generate new perspectives for the conservation of genetic resources at worldwide and taxonomic-wide scales
Isolation and characterization of nine tetranucleoide microsatellite loci for the secretive limbless lizards of the genus Anniella (Anguidae)
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Development and characterization of thirteen microsatellite markers for the Fiscal Flycatcher (Sigelus silens) for use in phylogeographic and landscape genetics research
The Fiscal Flycatcher, Sigelus silens, is the only representative of a monotypic genus, endemic to Southern Africa, and may represent two cryptic species. Here we describe the development of thirteen microsatellite markers, and characterize polymorphism for each one. We found that all but one of our 13 loci were highly variable, each having five or more alleles. This suggests that these markers will have high variability across the species range and will be of utility in understanding the extent of gene flow among populations
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Development and characterization of thirteen microsatellite markers for the Fiscal Flycatcher (Sigelus silens) for use in phylogeographic and landscape genetics research
The Fiscal Flycatcher, Sigelus silens, is the only representative of a monotypic genus, endemic to Southern Africa, and may represent two cryptic species. Here we describe the development of thirteen microsatellite markers, and characterize polymorphism for each one. We found that all but one of our 13 loci were highly variable, each having five or more alleles. This suggests that these markers will have high variability across the species range and will be of utility in understanding the extent of gene flow among populations
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Microsatellite markers for the Cape Robin-Chat (Cossypha caffra) and the Red-capped Robin-Chat (Cossypha natalensis) for use in demographic and landscape genetics analyses
The Robin-chats (Muscicapidae: Cossypha) are distributed across sub-saharan Africa with many species restricted to small fragments of Afromontane forest. Several species have decreasing population trends, so demographic data and landscape genetic data for these species will be essential for conservation management. Here we develop 23 microsatellite markers for two species of Cossypha (C. caffra and C. natalensis), characterize polymorphism, and cross-amplify a subset of loci. We demonstrate that most markers have high information content with many alleles suggesting that these markers will be useful for assessing population dynamics and demography. Several loci cross-amplified between species and retained high polymorphism, indicating that these loci will likely be of high utility for many species of African Robins
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Microsatellite markers for the Cape Robin-Chat (Cossypha caffra) and the Red-capped Robin-Chat (Cossypha natalensis) for use in demographic and landscape genetics analyses
The Robin-chats (Muscicapidae: Cossypha) are distributed across sub-saharan Africa with many species restricted to small fragments of Afromontane forest. Several species have decreasing population trends, so demographic data and landscape genetic data for these species will be essential for conservation management. Here we develop 23 microsatellite markers for two species of Cossypha (C. caffra and C. natalensis), characterize polymorphism, and cross-amplify a subset of loci. We demonstrate that most markers have high information content with many alleles suggesting that these markers will be useful for assessing population dynamics and demography. Several loci cross-amplified between species and retained high polymorphism, indicating that these loci will likely be of high utility for many species of African Robins
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Isolation and characterization of nine tetranucleoide microsatellite loci for the secretive limbless lizards of the genus Anniella (Anguidae)
Limbless lizards of the genus Anniella are found in the western United States and Mexico. Until recently only two species were known, but four new species have since been described. Since these lizards are fossorial, not much is known about the nature of gene flow within species, or if gene flow occurs across species boundaries in regions of overlap. Since these lizards are of conservation interest, we isolated and developed nine tetranucleotide microsatellite loci for the recently described species Anniella alexanderae. We characterized the polymorphism of each locus in A. alexanderae, and then cross-amplified these loci in five other Anniella species. These nine loci have high observed levels of heterozygosity and polymorphism information content, and were in Hardy-Weinberg equilibrium within the A. alexanderae samples we tested, indicating that they will have high utility in assessing population genetic and demographic patterns within Anniella