Background The thermal benefits of melanism in ectothermic animals are widely recognized,
but relatively little is known about population differentiation in the degree of melanism along …

Ecogeographical rules linking climate to morphology have gained renewed interest because
of climate change. Yet few studies have evaluated to what extent geographical trends …

There is substantial comparative and growing experimental evidence that the competition for
fertilization among sperm from different males can drive variation in male reproductive …

In most fishes, the number of offspring increases with maternal body size. Although this size‐
fecundity relationship often varies among species as a result of the coevolution of life‐history …

Environmental variation connected with seasonality is likely to affect the evolution of life-
history strategies in ectotherms, but there is no consensus as to how important life-history …

Environmental variation can promote differentiation in life-history traits in species of anurans.
Increased environmental stress usually results in larger age at sexual maturity, older mean …

The patterns of sex determination and sex differentiation have been shown to differ among
geographic populations of common frogs. Notably, the association between phenotypic sex …

In sharp contrast with birds and mammals, sex‐determination systems in ectothermic
vertebrates are often highly dynamic and sometimes multifactorial. Both environmental and …

The ability to store energy is an important life history trait for organisms facing long periods
without energy income, and in particular for capital breeders such as temperate zone …

Sperm competition theory predicts that among populations and species, male expenditure
on the ejaculate should increase with the strength of selection from sperm competition, a …