A comprehensive database of thermal developmental plasticity in reptiles

Abstract

How temperature influences development has direct relevance to ascertaining the impact of climate change on natural populations. Reptiles have served as empirical models for understanding how the environment experienced by embryos can influence phenotypic variation, including sex ratio, phenology and survival. Such an understanding has important implications for basic eco-evolutionary theory and conservation efforts worldwide. While there is a burgeoning empirical literature of experimental manipulations of embryonic thermal environments, addressing widespread patterns at a comparative level has been hampered by the lack of accessible data in a format that is amendable to updates as new studies emerge. Here, we describe a database with nearly 10, 000 phenotypic estimates from 155 species of reptile, collected from 300 studies manipulating incubation temperature (published between 1974–2016). The data encompass various morphological, physiological, behavioural and performance traits along with growth rates, developmental timing, sex ratio and survival (e.g., hatching success). This resource will serve as an important data repository for addressing overarching questions about thermal plasticity of reptile embryos.

Embryonic Temperature Programs Phenotype in Reptiles

“…On one hand, developmental rate displays a classic thermal response. As incubation temperature increases, reptile embryos develop faster and hatch sooner (reviewed in Noble et al, 2018). This pattern is clearly seen in snapping turtle embryos, which also display evidence of countergradient variation in developmental rate (Figure 2; Ewert et al, 2005).…”

“…While sex ratios provide a clear, albeit course, measure of temperature effects on cell, tissue, and organ differentiation, there are many other examples of persistent thermal effects on quantitative phenotypes in reptiles. Others have reviewed temperature effects on a wide range of traits (Rhen and Lang, 2004;Booth, 2018;Mitchell et al, 2018;Noble et al, 2018;While et al, 2018). Thus, we discuss just a few interesting examples of long-lasting effects on physiology and behavior.…”

“…This pattern is clearly seen in snapping turtle embryos, which also display evidence of countergradient variation in developmental rate (Figure 2; Ewert et al, 2005). Yet, hatchlings incubated at different temperatures are not simply exact replicas of each other (Rhen and Lang, 2004;Booth, 2018;Mitchell et al, 2018;Noble et al, 2018;While et al, 2018). Animals from different incubation temperatures are marked by differences in body size, body shape, amount of residual yolk, size of fat stores, locomotor performance, thermoregulatory behavior, sexual phenotype, and many other traits.…”

Introduction to the special issue—Developmental plasticity in reptiles: Physiological mechanisms and ecological consequences

“…This database will be updated annually as papers are continually published in the field, and there are plans to expand the database beyond studies of incubation temperature (e.g., to include studies of incubation moisture, maternal effects, etc.). See Noble et al (2018b) for details [Color figure can be viewed at wileyonlinelibrary.com] steady increase in publications over the past decades have made it difficult to draw overarching conclusions about the field's current state.…”

“…The goals of this symposium were to bring together scientists from around the world to review and synthesize the current state of the field, discuss gaps in knowledge, and identify ways to advance this area of reptile biology. This symposium was highly successful, which enabled a consolidation of research efforts to produce The Reptile Development Database, which is a new resource for researchers in this field (Noble et al., ; Figure ). This freely accessible database provides a means to address broad questions about reptile developmental plasticity and evaluate overarching patterns using meta‐analytic approaches.…”