(University of Veterinary Medicine — Vienna) Especially male poison frogs piggyback their offspring to pools in the rainforest. Now, researchers from Vetmeduni Vienna, the University of Vienna and Harvard University showed that this parental behavior can be triggered experimentally. With unrelated tadpoles placed on their backs, male — and even female — ‘foster parents’ behave as if they had picked up the tadpoles themselves. This showed for the first time that an external stimulus triggers complex behaviors in amphibians. Journal of Experimental Biology.