Fight or flight. They’re basic animal responses once considered purely instinctual—or perhaps strictly a natural learning process—but they may actually be a combination of the two. According to www.livescience.com, an experiment conducted at Missouri State University determined that wood-frogs can recognize predators before they’ve even hatched.
Since many amphibians associate the scent of a predator with the resulting distress pheromones of present same-species prey, scientists tested whether frogs could develop this keen association while still in the egg.
The result was a resounding yes. The group of wood-frog eggs exposed to both a distress pheromone and water that held fire-belly newts (a natural predator, not of wood-frogs, but of a different frog species) fell motionless at the presence of newt-scented water after they hatched—a telltale sign of predator recognition. The group of eggs that was only exposed to the newt-scented water yielded tadpoles who made no observed anti-predator response when exposed to it post-birth.