Actinic keratosis (AK) is a common skin condition caused by long-term sun exposure that has the potential to progress to non-melanoma skin cancers. The objective of this review is to examine the therapeutic options and management of AK globally, particularly in Australia, Canada, and the United Kingdom. Despite its potentially malignant nature, general awareness of AK is low, both in the general population and in the primary health care setting, especially in countries with low incidence. There is no standard therapeutic strategy for AK; it is treated through a variety of lesion-directed or field-directed therapies or a combination of both. A variety of treatment options are used depending on the experience of the primary care physician, the pathology of the lesion, and patient factors. Studies have shown that the physicians do not always use the optimal treatment option because of a lack of knowledge. The higher incidence of AK in fair-skinned people in Australia has resulted in well-established management strategies and guidelines for its treatment, compared with countries with lower incidence. It is essential to raise the awareness of AK because of its potential to progress to invasive squamous cell carcinoma. Primary care physicians are often the first to see this condition in their patients and are perfectly placed to educate the public and raise awareness. It is therefore desirable that their education and knowledge about AK and its treatment are up to date.Electronic supplementary materialThe online version of this article (doi:10.1007/s13555-015-0070-9) contains supplementary material, which is available to authorized users.

Identifying the relative contributions of genetic, maternal, and environmental factors to phenotypic variation is critical for evaluating the evolutionary potential of fitness-related traits. We employed a novel two-step cross-fostering experiment to quantify the relative contributions of clutch (i.e., maternal identity) and maternally chosen nest sites to phenotypic variation during three early life stages (incubation, hibernation, dispersal) of the painted turtle (Chrysemys picta). By translocating eggs between nests in the field, we demonstrated that both clutch and nest site contribute to phenotypic variation at hatching. Because hatchling C. pictahibernate inside nests, we performed a second cross-foster to decouple the effects of the incubation nest with that of the hibernation nest. Incubation nest explained little variation in phenotypes at spring emergence, but winter nest site was important. We found no evidence that mothers select nest sites specific to reaction norms of their own offspring, suggesting that females may select nest sites with microhabitats that broadly meet similar requirements across the population. After hibernation, we released hatchlings to assess performance and phenotypic selection during dispersal. Hibernation nest site influenced physiological performance during dispersal, and we detected nonlinear selection on hatchling carapace length. Our experiment demonstrates that nest-site choice has substantial effects on phenotypic variation and fitness across multiple early life stages. Abstract. Identifying the relative contributions of genetic, maternal, and environmental factors to phenotypic variation is critical for evaluating the evolutionary potential of fitnessrelated traits. We employed a novel two-step cross-fostering experiment to quantify the relative contributions of clutch (i.e., maternal identity) and maternally chosen nest sites to phenotypic variation during three early life stages (incubation, hibernation, dispersal) of the painted turtle (Chrysemys picta). By translocating eggs between nests in the field, we demonstrated that both clutch and nest site contribute to phenotypic variation at hatching. Because hatchling C. picta hibernate inside nests, we performed a second cross-foster to decouple the effects of the incubation nest with that of the hibernation nest. Incubation nest explained little variation in phenotypes at spring emergence, but winter nest site was important. We found no evidence that mothers select nest sites specific to reaction norms of their own offspring, suggesting that females may select nest sites with microhabitats that broadly meet similar requirements across the population. After hibernation, we released hatchlings to assess performance and phenotypic selection during dispersal. Hibernation nest site influenced physiological performance during dispersal, and we detected nonlinear selection on hatchling carapace length. Our experiment demonstrates that nest-site choice has substantial effects on phenotypic variation and fitness acro...

Historically, egg-bound reptile embryos were thought to passively thermoconform to the nest environment. However, recent observations of thermal taxis by embryos of multiple reptile species have led to the widely discussed hypothesis that embryos behaviorally thermoregulate. Because temperature affects development, such thermoregulation could allow embryos to control their fate far more than historically assumed. We assessed the opportunity for embryos to behaviorally thermoregulate in nature by examining thermal gradients within natural nests and eggs of the common snapping turtle (Chelydra serpentina; which displays embryonic thermal taxis) and by simulating thermal gradients within nests across a range of nest depths, egg sizes, and soil types. We observed little spatial thermal variation within nests, and thermal gradients were poorly transferred to eggs. Furthermore, thermal gradients sufficiently large and constant for behavioral thermoregulation were not predicted to occur in our simulations. Gradients of biologically relevant magnitude have limited global occurrence and reverse direction twice daily when they do exist, which is substantially faster than embryos can shift position within the egg. Our results imply that reptile embryos will rarely, if ever, have the opportunity to behaviorally thermoregulate by moving within the egg. We suggest that embryonic thermal taxis instead represents a play behavior, which may be adaptive or selectively neutral, and results from the mechanisms for behavioral thermoregulation in free-living stages coming online prior to hatching. KeywordsChelydra serpentina, microclim, nest, play, soil, snapping turtle, temperature Disciplines Ecology and Evolutionary Biology | Evolution | Population Biology CommentsThis article is from The American Naturalist 188 (2016) abstract: Historically, egg-bound reptile embryos were thought to passively thermoconform to the nest environment. However, recent observations of thermal taxis by embryos of multiple reptile species have led to the widely discussed hypothesis that embryos behaviorally thermoregulate. Because temperature affects development, such thermoregulation could allow embryos to control their fate far more than historically assumed. We assessed the opportunity for embryos to behaviorally thermoregulate in nature by examining thermal gradients within natural nests and eggs of the common snapping turtle (Chelydra serpentina; which displays embryonic thermal taxis) and by simulating thermal gradients within nests across a range of nest depths, egg sizes, and soil types. We observed little spatial thermal variation within nests, and thermal gradients were poorly transferred to eggs. Furthermore, thermal gradients sufficiently large and constant for behavioral thermoregulation were not predicted to occur in our simulations. Gradients of biologically relevant magnitude have limited global occurrence and reverse direction twice daily when they do exist, which is substantially faster than embryos can shift position within the...

Evolutionary theory predicts that dioecious species should produce a balanced primary sex ratio maintained by frequency-dependent selection. Organisms with environmental sex determination, however, are vulnerable to maladaptive sex ratios, because environmental conditions vary spatio-temporally. For reptiles with temperature-dependent sex determination, nest-site choice is a behavioural maternal effect that could respond to sex-ratio selection, as mothers could adjust offspring sex ratios by choosing nest sites that will have particular thermal properties. This theoretical prediction has generated decades of empirical research, yet convincing evidence that sex-ratio selection is influencing nesting behaviours remains absent. Here, we provide the first experimental evidence from nature that sex-ratio selection, rather than only viability selection, is probably an important component of nest-site choice in a reptile with temperature-dependent sex determination. We compare painted turtle (Chrysemys picta) neonates from maternally selected nest sites with those from randomly selected nest sites, observing no substantive difference in hatching success or survival, but finding a profound difference in offspring sex ratio in the direction expected based on historical records. Additionally, we leverage long-term data to reconstruct our sex ratio results had the experiment been repeated in multiple years. As predicted by theory, our results suggest that sex-ratio selection has shaped nesting behaviour in ways likely to enhance maternal fitness.