Life-history traits of Rana temporaria were studied in an alpine French population and in the literature. In the living frogs, mean adult body length was greater in females than in males. Sexual dimorphism in body length was 0.109 using Lovich & Gibbon  s (1992) formula, but tended to decrease with age. Age of adult frogs was assessed by skeletochronology, and age distribution was not signi®cantly different between the sexes (range 4±15 years in males, 5±12 in females). Adult survival rate was about 0.80 in both sexes. Once maturity was reached, the total expected longevity was 6.1 years in males and 5.5 years in females. Age and body length were positively correlated in both sexes. The growth coef®cient (K) was 0.47 in males, and 0.55 in females, mainly re¯ected as faster female growth between metamorphosis and maturation. Growth rate generally decreased before sexual maturity was reached. On average, females matured 1 year later than males. Newly metamorphosed froglets averaged 16.1 mm. When combined with published data from 12 European populations of R. temporaria, the following general patterns emerge. Mean adult body length is signi®cantly greater in females than in males, and mean body length at maturity shows the same trend. Variation in mean age at maturity and in longevity are considerable among populations, but there is no consistent trend of difference between the sexes. Body length and age are correlated between males and females, i.e. populations with long and old males also have long and old females. Mean adult body length, mean body length at maturity, age at maturity, and longevity all increase with decreasing activity period. Adults exposed to a short activity period grow slower but attain a greater ®nal length. Sexual dimorphism in body length generally increases as activity period gets shorter. Polygons describing norms of reaction for maturation in an age±body length space are similarly oriented in both sexes, but with a wider range in age for females. This is due to an older age at maturity for females in populations with a short activity season. Mean age and length at maturity are signi®cantly correlated in females, but not in males, partly supporting the hypothesis that this species has a¯exible pattern of development. Observed patterns are compared with predictions from life-history theory, paying attention to all life stages and environmental variation.

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International audienceWe describe the age structures of two neighbouring terrestrial salamander populations. The skeletochronological method was also used on larvae in utero and on new-born individuals. The age of adults was 8-24 years in population A, while males reached maturity at 3-5 years old and the youngest females were 6 years old in population B. Males and females from population B were also larger than those in population A. For the first time, lines of arrested growth (LAGs) were also found in the humerus of intra-uterine larvae and new-born individuals, indicating that young can spend up to 3 years in utero (population B) and up to 4 years (population A) before hatching. Growth of adults (fitted by the Bertalanffy model) also exhibited differences in growth coefficient (k) and mean asymptotic length (SVLmax) between sexes and populations. Local climatic conditions differed between the two areas of these populations and we hypothesize that the number of rainy days directly influences foraging during the short period of activity (< 3 months), leading to a delay in age at maturity, smaller length and growth rate, and increased gestation duration in the drier environment. The discussion is focused on proximate environmental influences on the variation of length and associated life-history traits in ectotherms, especially in terrestrial salamanders

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International audienceIn anuran competition over mates, disadvantaged (i.e., less competitive) males are generally known to be the smallest ones, but ages of those males have rarely been documented. In the context of a high level of male competition for mates, disadvantaged males were expected to use alternative mating tactics. To test for alternative tactics in a territorial toad (the spadefoot toad, Pelobates fuscus, Pelobatidae), daily breeding migration patterns were observed during 3 consecutive years. Relationships between migration pattern, operational sex ratio (OSR), and male's age (inferred from skeletochronological analysis), size, and mass were analysed. During 2 of the study years, OSRs were highly male-biased at the beginning of the breeding season and then gradually decreased when male numbers increased. Males with a low body condition index (CI) tend to arrive later and to lose relatively more mass than males with a higher CI. There was a negative relationship between percent mass loss per day and CI as well as length of stay in the breeding area, which suggests that a high energetic cost tactic was adopted by males with a higher CI. A negative relationship between length of stay and age was also observed. We conclude that based on competition for mates, male P. fuscus seem to adopt reproductive behaviour that differs according to body condition and age

Pelodytes punctatus est une espèce dont les biotopes de reproduction sont localisés en plaine principalement (90% des cas). De nouvelles données sur la phénologie de la reproduction ainsi que sur le type de milieu ont été collectées durant 6 ans sur 4 régions comprenant plus de 35 sites. La période de ponte principale survient au printemps mais on peut en observer une deuxième en automne dans le sud de la France. Les œufs sont fixés en cordons par les femelles sur les tiges de plantes aquatiques. Le succès de l'éclosion dépend de l'oxygénation de l'eau. La croissance larvaire est relativement rapide en conditions contrôlées (19°C ± 1°C) et les têtards se métamorphosent 40 à 60 jours après l'éclosion. Dans le sud, deux catégories de têtards sont observées en automne, les plus petits hivernent et se métamorphosent durant le printemps suivant.

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