M. Christopher Norris

The environment can alter the physiological condition of parents during reproduction, resulting in variation in energy allocation that can affect offspring performance. In addition, differences in energy allocation can affect how offspring respond to their own environmental heterogeneity. Consequently, specific parental effects can alter the developmental plasticity of offspring when both parents and offspring experience environmental variation. In this study, we assess how offspring developmental plasticity is affected by parental allocation using a breeding colony of brown anoles (Anolis sagrei) that varied in their caloric intake. Mothers fed a high-food diet laid larger eggs and were more fecund than mothers fed a low-food diet. Embryos from these mothers were then incubated across a range of ecologically relevant developmental temperatures. The reaction norm of hatchling body size, a trait crucial for fitness across ontogeny, differed between eggs laid from high-food and low-food mothers, suggesting that parental effects alter the developmental plasticity of offspring. This effect might be driven by the combination of an energetic constraint on reproduction and a thermodynamic constraint on development. Our results suggest that environmental variation experienced by previous generations affects the capacity of future generations to respond to their own environments.

Eggs of reptiles that inhabit hurricane-prone regions are often subjected to environmental stressors caused bythese storms. Some studies have examined how stress resulting from submersion in water or exposure to salinity affectsembryonic development and hatching success, but none have evaluated the effects of physical disturbances associatedwith strong winds. To demonstrate plausible effects of physical stressors associated with hurricane-force winds, we simulatedtwo situations that are likely experienced by eggs of Brown Anoles (Anolis sagrei), which inhabit areas affected byfrequent hurricanes. First, we simulated conditions during which eggs are blown or dropped from a standard 3-m height(e.g., like those in arboreal nests); second, we shook eggs to simulate physical disturbances associated with being vigorouslyblown by strong winds. We then compared hatching success, body size, and running performance of offspringfrom these treatments to control eggs/hatchings that were not disturbed during incubation. We demonstrated that eggsthat were dropped had reduced hatching success compared to both the shaken and control groups, but those shaken didnot differ from the control group. Additionally, we found no differences in hatchling body size or performance amongtreatments. Overall, our study demonstrated some resilience of Brown Anole eggs to major disturbances, which mightcontribute to the success of this species in highly disturbed habitats throughout its native and invasive ranges.

Water availability has critical impacts on numerous physiological functions in all organisms and can have different effects across life stages. For example, water available to reproductive females can influence offspring production, and has the potential to influence how early‐stage offspring (e.g., embryos) respond to moisture in their developmental environment. In this study, we use the brown anole lizard (Anolis sagrei) to examine the effects of water availability on reproductive investment. We tested the hypothesis that water available to mothers influences embryonic development under different levels of moisture in their incubation environment. We demonstrate that a substantial reduction in water availability to mothers (~70% reduction) has no observable effect on fecundity, egg size, or egg hydration. We also provide evidence that our water restriction to mothers does not influence how embryos respond to moisture conditions during egg incubation. However, moisture in the egg incubation substrate positively affected egg water uptake, egg hatching success and hatchling body size (but not hatchling hydration). Overall, our study shows that reproduction in adult female A. sagrei is robust to variation in water availability, but survival during early life stages is sensitive to this variable. Thus, the effect of water availability on different fitness components varies between life stages.

Developmental plasticity is the capacity of a single genotype to express multiple phenotypes in response to different early‐life environments. Such responses are defined by reaction norms, which may vary among individuals or populations. Variation in developmental reaction norms allows natural selection to operate on plasticity and is rarely examined in vertebrates. We quantified variation in embryonic developmental plasticity within and between populations using the brown anole lizard. We captured lizards from two islands in the Matanzas River (Florida, USA) and incubated their eggs under one of two multivariate treatments that mimicked the temperature, moisture and substrates of nest sites in either a shaded or open habitat. We measured hatchling morphology, performance, and physiology to quantify variation in family‐level reaction norms. We observed evidence of family‐level variation in reaction norms for morphology but not for performance or physiology, indicating an opportunity for natural selection to shape plasticity in hatchling body size. Overall, the results indicate that multiple abiotic conditions in natural nests combine to increase or reduce phenotypic variation, and that family‐level variation in reaction norms provides a potential for natural selection to shape plasticity.

Not-yet-known not-yet-known not-yet-known unknown Developmental plasticity is the capacity of a single genotype to express multiple phenotypes in response to different early-life environments. Such responses are defined by reaction norms, which may vary among individuals or populations. Variation in developmental reaction norms allows natural selection to operate on plasticity and is rarely examined in vertebrates. We quantified variation in embryonic developmental plasticity within and between populations using the brown anole lizard. We captured lizards from two islands in the Matanzas River (Florida, USA) and incubated their eggs under one of two multivariate treatments that mimicked the temperature, moisture, and substrates of nest sites in either a shaded or open habitat. We measured hatchling morphology, performance, and physiology to quantify variation in family-level reaction norms. We observed evidence of family-level variation in reaction norms for morphology but not for performance or physiology, indicating an opportunity for natural selection to shape plasticity in hatchling body size. Overall, the results indicate that multiple abiotic conditions in natural nests combine to increase or reduce phenotypic variation, and that family-level variation in reaction norms provides a potential for natural selection to shape plasticity.

Behaviour is influenced by many factors, including morphology, performance capabilities and the surrounding environment. Behavioural adjustments in response to these factors have important fitness consequences, and therefore behaviour should be considered when evaluating relationships among morphology, performance and fitness. We used hatchling fence lizards (Sceloporus undulatus) to test if sprinting speed and movement behaviours (e.g. latency to approach prey, number of pauses when fleeing or foraging) differ between foraging and anti-predator contexts and if these behaviours are associated with body size, locomotor performance capacity and survival. We quantified maximal sprint performance of individuals and evaluated their running speed in laboratory trials of foraging (moving towards crickets) and predator escape (response to a swooping avian predator). We show that hatchlings run at ~17–36% of total capacity when foraging. Although the most common anti-predator behaviour was to remain still, those that fled from the predator ran at full burst speed. However, foraging and escape speed/behaviours were not associated with body size or locomotor capacity. Hatchlings were subsequently released at our field site for a recapture study to assess phenotypic relationships with survival. We found no evidence that survival was influenced by performance or behaviour, but body size was positively related to survival in the field. These results highlight how seemingly important fitness-relevant behavioural and performance traits may not mediate the relationship between body size and survival.