Knock-On Effects of Environmental Influences during Embryonic Development of Ectothermic Vertebrates
Bror Jönsson, Nina Jönsson, Michael M. Hansen
Abstract
Environmental factors influencing parents or offspring during embryogenesis can have knock-on effects at later life stages of the offspring. These effects may prepare the progeny for conditions that they may encounter as larvae, juveniles, and/or adults. Here, we give examples on how knock-on effects of temperature and predator cues can affect phenotypes of fish, amphibians, and reptiles. Such effects are best described in reptiles, but are generally widespread among ectotherms. Most of the species are oviparous with egg incubation outside the mother's body. The eggs can be exposed to highly different and variable environmental conditions, and developmental plasticity may help offspring cope with influences they may encounter at a later stage, e.g., whether the habitat will be warmer or colder and/or safer or riskier