Effects of induced variation in anuran larval development on postmetamorphic energy reserves and locomotion

Abstract

Anuran larvae exhibit high levels of phenotypic plasticity in growth and developmental rates in response to variation in temperature and food availability. We tested the hypothesis that alteration of developmental pathways during the aquatic larval stage should affect the postmetamorphic performance of the Iberian painted frog (Discoglossus galganoi). We exposed tadpoles to different temperatures and food types (animal- vs. plant-based diets) to induce variation in the length of the larval period and body size at metamorphosis. In this species, larval period varied with temperature but was unaffected by diet composition. In contrast, size at metamorphosis was shaped by the interaction between food quality and temperature; tadpoles fed on an animal-based diet became bulkier metamorphs than those fed on plant-based food at high (22°C) but not at low (12°C) temperature. Body condition of newly metamorphosed frogs was unrelated to the temperature or food type experienced during the premetamorphic stage. Frogs maintained at high temperature during the larval period showed reduced jumping ability, especially when fed on the plant-based diet. However, when considering size-independent jumping ability, cold-reared individuals exhibited the lowest performance, and herbivores reared at 17°C the highest. Cold-reared (12°C) frogs accumulated larger amounts of energy reserves than individuals raised at 17°C or 22°C. This was still the case after correction for differences in body mass, thus indicating some size-independent effect of developmental temperature. Despite the higher lipid content of the carnivorous diet, the differences in energy reserves between herbivores and carnivores were relatively weak and associated with differences in body size. These results suggest that the consequences of environmental variation in the larval habitat can extend to the terrestrial phase and influence juvenile growth and survival.

Developmental plasticity mirrors differences among taxa in spadefoot toads linking plasticity and diversity

“…In addition, there has been ample opportunity for selection to act on morphology. Relative limb length and head length have functional relevance for locomotion and feeding, and their plasticity in relation to shifts in life-history traits has been studied in detail (34,(49)(50)(51)(52). Observed plastic changes in morphology within species were relatively minor (1-5% in length), and they were unlikely to have a high impact on locomotor performance or predator escape efficiency (31), and thus they were unlikely to have large effects on fitness and to be the direct target of natural selection.…”

Temperature and UV-B insensitive performance in tadpoles of the Ornate burrowing frog: an ephemeral pond specialist

“…UV-B radiation causes cellular damage through the absorption of radiation by DNA, which must be repaired to limit disruption to DNA transcription (Friedburg et al, 2006). The consequences of UV-B exposure during development include reduced growth rates (Tevini, 1993;Caldwell et al, 1998), reduced locomotor ability (Álvarez and Nicieza, 2002), reduced metabolic scope (Ylonen et al, 2004) and increased time to metamorphosis in tadpoles (Belden et al, 2000;Pahkala et al, 2001;Belden and Blaustein, 2002;Pahkala et al, 2003). These effects indicate energy allocation to repair UV-Binduced DNA damage (Alton et al, 2012).…”

Offering offspring as food to cannibals: oviposition strategies of Amazonian poison frogs (Dendrobates ventrimaculatus)

“…As a consequence, their offspring have limited chances to move to new resources, and therefore might compete locally for limited resources (Stephens and Krebs 1986;Mayhew 1997;Mock and Parker 1997). The direct relationship between resource quality-in terms of food availability, stability, risk of predation and competition-and the number and quality of offspring implies that there is strong selection on resource-selection behavior of parents (Godfray 1994;Mayhew 1997;Alford 1999;Á lvarez and Nicieza 2002;Altwegg and Reyer 2003;Lehtinen 2004). The ''oviposition-preference-offspring-performance'' hypothesis therefore predicts that female oviposition decisions are selected to maximize fitness by maximizing larval performance (Thompson 1988;Mayhew 1997).…”