Baby sharks developing in their egg cases stay still in order to avoid to avoid being detected by predators, a new study in PLoS ONE has found.

Since the shark ability is innate and based on electrical field detectors, the discovery could soon lead to improved shark deterrents that keep the toothy creatures away from us without hurting them.

“Despite being confined to a very small space within an egg case where they are vulnerable to predators, embryonic sharks are able to recognize dangerous stimuli and react with an innate avoidance response,” Ryan Kempster from the University of Western Australia, was quoted as saying in a press release.

He added, “Knowledge of such behaviors may help us to develop effective shark repellents.”

It’s been known for some time that adult sharks use highly sensitive receptors to detect electric fields emitted by potential prey. The current study found that embryos of some shark species employ similar means to detect potential predators and escape being eaten.

For example, even within their egg cases, brown-banded bamboo shark embryos can sense electric fields that mimic a predator. They respond by reducing respiratory gill movements to avoid detection. Even at these early stages of development, embryonic sharks can recognize dangers and instinctively try to avoid them.

Humans seem to develop such skills later. As human babies learn to crawl, their brains also lear to detect danger.

(Image: Embryonic bamboo shark in egg case; Credit: Ryan Kempster)