Successful Invasion Into New Environments Without Evidence of Rapid Adaptation by a Predatory Marine Gastropod.

Invasive species with native ranges spanning strong environmental gradients are well suited for examining the roles of selection and population history in rapid adaptation to new habitats, providing insight into potential evolutionary responses to climate change. The Atlantic oyster drill (Urosalpinx cinerea) is a marine snail whose native range spans the strongest coastal latitudinal temperature gradient in the world, with invasive populations established on the US Pacific coast. Here, we leverage this system using genome-wide SNPs and environmental data to examine invasion history and identify genotype-environment associations indicative of local adaptation across the native range, and then assess evidence for allelic frequency shifts that would signal rapid adaptation within invasive populations.

Divergent sensory and immune gene evolution in sea turtles with contrasting demographic and life histories.

Sea turtles represent an ancient lineage of marine vertebrates that evolved from terrestrial ancestors over 100 Mya. The genomic basis of the unique physiological and ecological traits enabling these species to thrive in diverse marine habitats remains largely unknown. Additionally, many populations have drastically declined due to anthropogenic activities over the past two centuries, and their recovery is a high global conservation priority.

Good from far, but far from good: The impact of a reference genome on evolutionary inference.

Genomic diversity and past population histories are key considerations in the fields of conservation and evolutionary biology. In this issue of Molecular Ecology Resources, Prasad et al. (Mol.

Metabolic Rates and Thermal Thresholds of Embryonic Flatback Turtles () from the North West Shelf of Australia.

AbstractNest microclimates influence embryonic development and survival in many lineages, including reptiles with temperature-dependent sex determination. These microclimates are dependent on physical drivers and biological processes, such as embryonic metabolism, that generate heat. The flatback turtle () has among the largest hatchlings of the seven extant sea turtle species, making it an excellent candidate for quantifying the contribution of embryonic metabolism to the nest microclimate.

No evidence of selection against anomalous scute arrangements between juvenile and adult sea turtles in Florida.

Variations in the number and arrangement of scutes often are used for species identification in hard-shelled sea turtles. Despite the conserved nature of scute arrangements, anomalous arrangements have been noted in the literature for over a century, with anomalies linked to sub-optimal environmental conditions in the nest during development. Long-held assumptions suggest that anomalous scute arrangements are indicative of underlying physiological or morphological anomalies, with presumed long-term survival costs to the individual.

Incubation environment and parental identity affect sea turtle development and hatchling phenotype.

For reptiles, the incubation environment experienced by embryos during development plays a major role in many biological processes. The unprecedented rate of climate change makes it critical to understand the effects that the incubation environment has on developing embryos, particularly in imperiled species such as chelonians. Consequently, a number of studies have focused on the effects of different environmental conditions on several developmental processes and hatchling phenotypic traits.

Microclimate modelling of beach sand temperatures reveals high spatial and temporal variation at sea turtle rookeries.

The continual development of ecological models and availability of high-resolution gridded climate surfaces have stimulated studies that link climate variables to functional traits of organisms. A primary constraint of these studies is the ability to reliably predict the microclimate that an organism experiences using macroscale climate inputs. This is particularly important in regions where access to empirical information is limited.

Environmental Causation of Turtle Scute Anomalies in ovo and in silico.

The turtle shell is often described as an evolutionary novelty that facilitated the radiation of the clade Testudines. The scutes, or keratinous plates, of the turtle shell are hypothesized to be patterned by reaction-diffusion dynamics, and this property of their development provides explanatory power to mechanisms of anomalous variation. A mathematical model of scute development predicts that anomalous variation in the phylogenetically stable pattern of scutes is achieved by environmental influence on the developmental program.

Loggerhead sea turtle embryos (Caretta caretta) regulate expression of stress response and developmental genes when exposed to a biologically realistic heat stress.

Oviparous reptile embryos are expected to breach their critical thermal maxima if temperatures reach those predicted under current climate change models due to the lack of the maternal buffering processes and parental care. Heat-shock proteins (HSPs) are integral in the molecular response to thermal stress, and their expression is heritable, but the roles of other candidate families such as the heat-shock factors (HSFs) have not been determined in reptiles. Here, we subject embryonic sea turtles (Caretta caretta) to a biologically realistic thermal stress and employ de novo transcriptomic profiling of brain tissue to investigate the underlying molecular response.

No evidence of sperm conjugate formation in an Australian mouse bearing sperm with three hooks.

Sperm conjugation occurs when two or more sperm physically unite for motility or transport through the female reproductive tract. In many muroid rodent species, sperm conjugates have been shown to form by a single, conspicuous apical hook located on the sperm head. These sperm "trains" have been reported to be highly variable in size and, despite all the heads pointing in roughly the same direction, exhibit a relatively disordered arrangement.