Andaman Islands: The 'upside-down' sex life of a rare Indian frog revealed

In India, a species of frogs mate and lay their eggs while upside down, a new study has found.

British Broadcasting CorporationWatchHomeNewsSportBusinessInnovationCultureTravelEarthVideoLiveHomeNewsIsrael-Gaza WarWar in UkraineUS ElectionUS & CanadaUKUK PoliticsEnglandN. IrelandN. Ireland PoliticsScotlandScotland PoliticsWalesWales PoliticsAfricaAsiaChinaIndiaAustraliaEuropeLatin AmericaMiddle EastIn PicturesBBC VerifySportBusinessExecutive LoungeTechnology of BusinessWomen at the HelmFuture of BusinessInnovationTechnologyScience & HealthArtificial IntelligenceAI v the MindCultureFilm & TVMusicArt & DesignStyleBooksEntertainment NewsTravelDestinationsAfricaAntarcticaAsiaAustralia and PacificCaribbean & BermudaCentral AmericaEuropeMiddle EastNorth AmericaSouth AmericaWorld’s TableCulture & ExperiencesAdventuresThe SpeciaListEarthNatural WondersWeather & ScienceClimate SolutionsSustainable BusinessGreen LivingVideoLiveLive NewsLive SportHomeNewsSportBusinessInnovationCultureTravelEarthVideoLiveAudioWeatherNewslettersThe 'upside-down' sex life of a rare Indian frog revealedBBCThe Charles Darwin frog, named after the famous naturalist, is endemic to a few islands in the AndamansIn the Andaman islands straddling India’s east coast, a species of frogs mate and lay their eggs while upside down, a new study has found.

Both the male and female Charles Darwin frogs position themselves upside down on the walls of tree cavities, with their bodies entirely out of water, scientists from India and the US say in their paper. Hatchlings drop into the water below and develop through a free-swimming tadpole stage.

“This is remarkable. Upside-down spawning is the most unique behaviour in this frog. No other frog is known to lay eggs on inner walls of tree holes in an upside-down posture with bodies completely outside water,” says SD Biju of the University of Delhi and currently a fellow at the Harvard Radcliffe Institute.

"This discovery is fundamental for understanding how this species interacts with its environments and which habitats are essential for its survival."

Nearly all the world’s 7,708 frog species mate and spawn in water and other terrestrial habitats. They also use external fertilisation: the female lays eggs during mating, while the male releases sperm to fertilise them.

https://www.bbc.com/news/articles/c897l72rl5po

---