The role of plasticity in shaping adaptations is important to understanding the expression of traits within individuals and the evolution of populations. With increasing human impacts on the environment, one challenge is to consider how plasticity shapes responses to anthropogenic stressors such as contaminants. To our knowledge, only one study (using mosquitoes) has considered the possibility of induced insecticide tolerance. Using populations of wood frogs (Lithobates sylvaticus) located close to and far from agricultural fields,...

The rise of sexual dimorphism is thought to coincide with the evolution of sex chromosomes. Yet because sex chromosomes in many species are ancient, we lack empirical evidence of the earliest stages of this transition. We use QTL analysis to examine the genetic architecture of sexual dimorphism in subdioecious octoploid Fragaria virginiana. We demonstrate that the region housing the male-function locus controls the majority of quantitative variation in proportion fruit set, confirming the existence of...

Although adaptive plasticity would seem always to be favored by selection, it occurs less often than expected. This lack of ubiquity suggests that there must be trade-offs, costs, or limitations associated with plasticity. Yet, few costs have been found. We explore one type of limitation, a correlation between plasticity and developmental instability, and use quantitative genetic theory to show why one should expect a genetic correlation. We test that hypothesis using the Landsberg erecta ×...

Anthropogenic environmental change is a powerful and ubiquitous evolutionary force, so it is critical that we determine the extent to which organisms can evolve in response to anthropogenic environmental change and whether these evolutionary responses have associated costs. This issue is particularly relevant for species of conservation concern including many amphibians, which are experiencing global declines from many causes including widespread exposure to agrochemicals. We used a lab toxicity experiment to assess variation in sensitivity...

Deciphering the mechanisms involved in shaping social structure is key to a deeper understanding of the evolutionary processes leading to sociality. Individual specialization within groups can increase colony efficiency and consequently productivity. Here, we test the hypothesis that within-group variation in individual personalities (i.e. boldness and aggression) can shape task differentiation. The social spider Stegodyphus sarasinorum (Eresidae) showed task differentiation (significant unequal participation) in simulated prey capture events across 10-day behavioural assays in the field,...

1. Color patterns on flowers can increase pollinator visitation and enhance foraging behavior. Flowers uniform in color to humans, however, can appear patterned to insects due to spatial variation in UV-reflectance on petals. A UV ‘bullseye’ pattern that is common among angiosperms—UV-absorbing petal bases and reflective apices—purportedly functions as a nectar guide, enhancing pollinator orientation, and experimental evidence suggests that UV reflectance increases apparency to pollinators. 2. We test the pollinator-attracting and -orienting functions of...

Although color polymorphisms are a widespread and conspicuous component of extant biodiversity, the selective pressures that act to maintain multiple morphs within populations remain poorly understood in most cases. In particular, the role that visual system limitations may play in maintaining multiple color morphs is not well explored. We used a female-limited color polymorphism common to the butterfly genus Colias, called the ‘alba’ polymorphism, to investigate the hypotheses that mate-searching males may struggle to discriminate...

PREMISE OF THE STUDY: Hybrid zones provide ‘natural laboratories’ for understanding the processes of selection, reinforcement and speciation. We sought to gain insight into the degree of introgression and the extent of ecological/phenotypic intermediacy in the natural hybrid strawberry, Fragaria × ananassa subsp. cuneifolia. METHODS: We used whole plastome sequencing to identify parental species-specific (Fragaria chiloensis and F. virginiana) chloroplast SNPs, and combined the use of these with nuclear microsatellite markers to genetically characterize the...

Eastern deciduous forests are changing in species composition and diversity outside of classical successional trajectories. Three disturbance mechanisms appear central to this phenomenon: fire frequency is reduced, canopy gaps are smaller, and browsers are more abundant. Which factor is most responsible is a matter of great debate and remains unclear, at least partly because few studies have simultaneously investigated more than one process. We conducted a large-scale experiment in mesophytic forests of West Virginia, USA,...