From Oviparity to Marsupialism: Strange Modes of Reproduction in Amphibians

Abstract

Amphibians are among the first vertebrates that have conquered the terrestrial environment. Their way of life is characterized by a compulsory aquatic larval phase and an adult terrestrial phase separated by a metamorphosis. Amphibians remain subservient to the aquatic environment throughout their lives. Several adaptive mechanisms regarding reproductive patterns have been established during biological evolution. Some species are oviparous; others are viviparous or direct-developing. Fertilization can be external or internal. Alongside these conventional breeding methods, some amphibians have developed particular forms of marsupialism or transport of eggs and larvae allowing them to at least partially free themselves from the aquatic environment.

Environmental sympatry through time: spatio-temporal distribution and conservation status of two sympatric anuran species (Leptodactylidae) in South America

“…Extreme drought events coupled with hydrological variations could compromise their physiological tolerance thresholds and decrease their reproductive performances (Hijmans et al, 2005;Menéndez-Guerrero et al, 2020). Our results suggest that the loss of anuran environmental niches could increase environmental sympatry, pressuring spatial responses coupled with competition; new ecophysiological barriers derived from climatic and anthropic barriers (Bruzzi-Lion et al, 2019;Exbrayat, 2018). In this sense, since the period of reproductive activity of anurans is associated with seasonality, changes in climatic and environmental dynamics could modify the reproductive activities of these species (Medina et al, 2020).…”

“…Our target species could respond to these landscape characteristics, associating with lowlands with historical climatic and hydrological stability (Andrade-Díaz et al, 2021;Menéndez-Guerrero et al, 2020). Climate change in synergy with anthropic actions could cause alarming declines not only in the environmental niches of these species but also in anuran biodiversity and their critical habitats (Alvarez et al, 2021;Alvarez et al, 2022;Exbrayat, 2018;Menéndez-Guerrero et al, 2020).…”

“…This added to the regionally intensified land use, could modify the spatial and demographic patterns of currently stable populations (De Marzo et al, 2022). The reproductive modes of anurans could emerge as determinants of their reproductive success; for most species, reproduction occurs during the warm season, coinciding with the rainy season (Exbrayat, 2018).…”