Contrasting life-histories in two syntopic amphibians of the Leptodactylus fuscus group (Heyer 1978)

Abstract

We used skeletochronology to compare age, size, reproductive parameters and growth patterns of two related, anuran amphibians from Northern Argentina: Leptodactylus bufonius (n=69) and L. latinasus (n=56), in order to better understand their coexistence in syntopy. Previous studies showed that the two species overlap in their dietary requirements and utilize the same habitats for feeding and breeding. We found that their life-history patterns are significantly different, L. bufonius being larger, and having a higher reproductive output and lifespan, compared to the smaller and shorter-living L. latinasus. Since none of the species exhibited sexual size dimorphism, and both acquired sexual maturity after the first year of life, we suggest that the differences in the observed life-history parameters must appear during early stages of development, during larval and/or juvenile stages.

Older males whistle better: Age and body size are encoded in the mating calls of a nest-building amphibian (Anura: Leptodactylidae)

“…Our findings suggest that the mating calls in L. bufonius could promote female mate choice in relation to both size and age. It is noteworthy that size and age were encoded separately within the two spectral parameters analyzed, which is in line with previous results that showed that age and size do not follow a linear relationship in this species, meaning that larger individuals are not necessarily older (Marangoni et al, 2019). In addition, both spectral parameters were static, favoring individual recognition (Gerhardt, 1991).…”

“…Thus, females of this species are provided with the necessary information to opt for smaller/larger males from younger/older age classes, which may bring combined advantages stemming from both traits and ultimately favor males with certain life-history strategies (Table 2). Based on a previous study (Marangoni et al, 2019) regarding the life-history strategies of the same population of L. bufonius (Corrientes, Argentina), the prevalent strategy observed was "fast growth-early sexual maturity." This strategy is in line with the reproductive behavior and ecology of the species, since the breeding events and reproductive success are highly dependent on the seasonal precipitation regimes and water bodies with high desiccation rates.…”

“…Field work was carried out by FM during autumn 2007 -spring 2008, about 10 km northeast from Corrientes city, Argentina, within an area with numerous temporary −58.747844). A more detailed description of the study area is provided by Marangoni et al (2019). The mating calls were recorded in the field for 18 L. bufonius males during evening hours, from 20:00 to 22:00, using a Sony TCM-313 tape recorder.…”

“…Air temperature and humidity were recorded at the beginning of each individual recording with a handheld thermo-hygrometer. The corresponding individual age and body size measurements (i.e., body mass, snout-vent length, head width, right hind-limb length, arm length, and tibia length) for the 18 adult males were obtained from Marangoni et al (2019). Briefly, snout-vent length and right hind-limb length were measured on laminated graph paper (accuracy ±1 mm), while head width, arm length, and tibia length were measured to the nearest 0.1 mm with digital calipers.…”

Age structure and growth pattern of a high‐altitude lizard population based on age determination by skeletochronology

“…Skeletochronology calculates the calcific "annual rings" or "growth markers" in hard tissues (Castanet, 1994), which are recorded in various bone tissues, such as skulls (Mitchell, 1973), vertebrae (Scholz et al, 2010), teeth (Smirina & Ananjeva, 2007), and long bones. In effect, long bones such as phalanges, metatarsals, tibias, fibulae, humeri, and femurs are all commonly used in skeletochronology (Cabezas‐Cartes et al, 2018; Curtin et al, 2015; Guarino et al, 2019; Marangoni et al, 2019; Petermann & Gauthier, 2020). Most long bones have two growth plates and grow simultaneously at both ends (Boskey & Coleman, 2010).…”