White-edged cowards: high-pitched treefrogs will be attacked by those with orange legs

Anurans are one of the most diverse groups of animals, with single and multi-modal communication forms commonly used to settle disputes over territory and to attract females. Thus, I aimed to evaluate if male white-edged treefrogs tend to attack smaller individuals and which morphometric factor is related to it. Advertisement calls of this species were recorded and used in a four-choice experiment with the emission of artificially designed calls. I evaluated which speaker individuals approached and if morphometric variables could predict it. I observed that individuals approached significantly more often towards the high-pitched call than other treatments, and the frequency to do so was predicted by the extension of orange colour in their legs. These results indicate that smaller individuals are actively excluded from calling sites.

Reproductive behaviors promote ecological and phenotypic sexual differentiation in the critically endangered Lehmann’s poison frog

Territoriality and parental care are complex reproductive behaviors found in many taxa from insects to mammals. Parental care can be carried out by the female, the male, or both, depending on the species. Territoriality, in contrast, is predominantly displayed by males. Different selective pressures imposed on individuals from the sex performing territorial or parental care behaviors may also lead to sexual differentiation in other life-history traits. Due to their territorial behavior and their diversity of parental care behaviors, Neotropical poison frogs are an excellent study system to investigate whether behavioral traits can influence sexual differentiation in intrinsic or extrinsic traits of individuals. Here, we evaluate whether territorial and parental care behaviors mediate sexual differentiation in ecological (habitat use) and phenotypic (coloration, morphology) traits in the critically endangered Lehmann’s poison frog (Oophaga lehmanni), a species in which males defend territories while females provide parental care. We found sex differences in habitat use and morphological traits, but not in coloration. Males use trunks and green leaves as perches more frequently and are found on higher substrates, than females. We found no sex differences in body size, but females have longer arms than males, which is probably associated with their parental duties (climbing trees to feed the tadpoles). Altogether, our results provide evidence that selection pressures act differently on male and female traits, and that territoriality and parental care may promote the evolution of sexual differentiation in dendrobatids. Long-term wildlife observations are essential to identify important life-history traits and to evaluate hypotheses about the behavioral ecology and conservation of this and other vertebrate species.

Sexual size and shape dimorphism in Turkish common toads (Bufo bufo Linnaeus 1758)

Differences in male and female traits (sexual dimorphism [SD]) are widespread in animals. Dimorphism in morphological characters evolves under the effect of environmental and genetic factors and is shaped by natural and sexual selection. In this study, intersexual differences in size and shape in common toad, Bufo bufo, populations in Turkey were investigated. For this, linear measurements of 27 body-related morphometric characters in a sample of 140 individuals (70 males and 70 females) were compiled. The data were analyzed using univariate and multivariate statistical methods. The results show SD in body size with females having larger body size, a trait related with fecundity and thus probably under sexual selection. Body shape differences, which are associated with head width and dorsal head, are likely to prey size. Male-biased differences observed in nasal characters and tympanum may also be associated with sexual selection (male-male competition). Our findings are consistent with previous studies of major of Anura and support a role for selection pressures acting differentially upon individuals from both sexes, resulting in the evolution of sexually dimorphic traits.

A new reproductive mode in anurans: Natural history of Bokermannohyla astartea (Anura: Hylidae) with the description of its tadpole and vocal repertoire

Anurans have the greatest diversity of reproductive modes among tetrapod vertebrates, with at least 41 being currently recognized. We describe a new reproductive mode for anurans, as exhibited by the Paranapiacaba Treefrog, Bokermannohyla astartea, an endemic and poorly known species of the Brazilian Atlantic Forest belonging to the B. circumdata group. We also describe other aspects of its reproductive biology, that are relevant to understanding the new reproductive mode, such as courtship behavior, spawning, and tadpoles. Additionally, we redescribe its advertisement call and extend its vocal repertoire by describing three additional call types: courtship, amplectant, and presumed territorial. The new reproductive mode exhibited by B. astartea consists of: (1) deposition of aquatic eggs in leaf-tanks of terrestrial or epiphytic bromeliads located on or over the banks of temporary or permanent streams; (2) exotrophic tadpoles remain in the leaf-tanks during initial stages of development (until Gosner stage 26), after which they presumably jump or are transported to streams after heavy rains that flood their bromeliad tanks; and (3) tadpole development completes in streams. The tadpoles of B. astartea are similar to those of other species of the B. circumdata group, although with differences in the spiracle, eyes, and oral disc. The vocal repertoire of B. astartea exhibits previously unreported acoustic complexity for the genus. Bokermannohyla astartea is the only bromeligenous species known to date among the 187 known species within the tribe Cophomantini. We further discuss evolutionary hypotheses for the origin of this novel reproductive mode.

Reproduction and metamorphosis in the Myristica Swamp tree frog, Mercurana myristicapalustris (Anura: Rhacophoridae)

The reproductive biology of the Myristica Swamp tree frog (Mercurana myristicapalustris), a monotypic rhacophorid frog endemic to the foothills of the Western Ghats mountains of India, has remained unknown since the description of the genus and species. We monitored individuals from parental generation amplexus to the completion of offspring generation tadpole metamorphosis. Surprisingly, our observations revealed that this species exhibits many previously unknown characteristics, including the first ever record of the female, and a diverse call repertoire, consisting of five different call types (the functions of which remain incompletely known). We were also able to determine that reproductive activity peaked during the late pre-monsoon season, that males engaged in intraspecific aggressive encounters to occupy and to defend desirable territories, and that oviposition took place in terrestrial nests made by females. Embryonic development in the unattended nest was followed by tadpole development, which concluded within 40 days. The specific breeding mode employed by Mercurana, which restricts its range to the endangered Myristica swamp ecosystem, likely renders it susceptible to multiple threats, which should be considered jointly in future conservation planning.