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Marine megafauna species are affected by a wide range of anthropogenic threats. To evaluate the risk of such threats, species’ vulnerability to each threat must first be determined. We build on the existing threats classification scheme and ranking system of the International Union for Conservation of Nature (IUCN) Red List of Threatened Species by assessing the vulnerability of 256 marine megafauna species to 23 at‐sea threat...
Bilateral anterior amelia (BAA) is the congenital absence of thoracic limbs and has been reported in the Chihuahua as an autosomal recessive disorder. In some cases, the digits of the pelvic limbs can be variably affected, but otherwise, the pelvic limbs are generally spared. A GWAS performed with nine BAA affected Chihuahuas identified a significant association on chromosome 13, and homozygosity mapping delineated a 2.1 Mb ch...
Beach erosion aggravates the drastic decline in marine turtle populations in French GuianaNARA Subscribed
Yalimapo beach, near the Maroni River estuary in French Guiana, is an important turtle nesting site. The interaction of massive mud banks migrating alongshore from the distant Amazon River with discharge from the Maroni River generates strong beach morpho-sedimentary changes. The eventual degradation of the marine turtle nesting habitats resulting from these changes represents a threat to the offspring, and consequently, to th...
Evidence of backcross inviability and mitochondrial DNA paternal leakage in sea turtle hybridsNARA Subscribed
Hybridization is known to be part of many species' evolutionary history. Sea turtles have a fascinating hybridization system in which species separated by as much as 43 million years are still capable of hybridizing. Indeed, the largest nesting populations in Brazil of loggerheads ( Caretta caretta ) and hawksbills ( Eretmochelys imbricata ) have a high incidence of hybrids between these two species. A third species, olive rid...
Under the isolation‐by‐distance model, the strength of spatial genetic structure (SGS) depends on seed and pollen dispersal and genetic drift, which in turn depends on local demographic structure. SGS can also be influenced by historical events such as admixture of differentiated gene pools. We analysed the fine‐scale SGS in six populations of a pioneer tree species endemic to Central Africa, Aucoumea klaineana . To infer the...
Fine‐scale genetic structure and gene dispersal inferences in 10 Neotropical tree speciesNARA Subscribed
The extent of gene dispersal is a fundamental factor of the population and evolutionary dynamics of tropical tree species, but directly monitoring seed and pollen movement is a difficult task. However, indirect estimates of historical gene dispersal can be obtained from the fine‐scale spatial genetic structure of populations at drift–dispersal equilibrium. Using an approach that is based on the slope of the regression of pairw...
Mineral nitrogen cycling through earthworm casts in a grazed pasture under elevated atmospheric CO 2NARA Subscribed
We used the New Zealand grazed pasture free air CO 2 enrichment experiment to determine the effects of elevated CO 2 on earthworm ( Aporrectodea caliginosa and Lumbricus rubellus ) cast production and mineral nitrogen (N) concentration over a 5‐week period in the spring. Elevated CO 2 did not affect earthworm biomass or the amount of cast material produced. However, cast mineral N concentrations were 18% lower, resulting in 27...
Habitat specialist species are supposed to be more susceptible to variations in local environmental characteristics than generalists. To test this hypothesis, we conducted a comparative analysis on abundance and genetic diversity of forest carabids differing in their habitat requirements. Four species were sampled in forests characterized by abiotic, landscape and biotic environmental variables. A statistical framework based o...
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