A new research has suggested that tiny sharks, which are similar to human in sizes, have a particular type of superpower. It has been discovered that their bellies glow. The findings of the study suggest that the reason behind the glow in their belly is to hide them and hence, protect themselves from predators creeping behind them.

Study researcher Julien Claes of the University Catholique de Louvain in Belgium, said, “Scientists had proposed the smalleye pygmy shark (Squaliolus aliae) sported light-emitting organs called photophores for use in camouflage, but that was never really tested. It wasn't even known if these organs were really functional, able to produce light”.

In order to find out that the organ actually produced light, Claes and his colleague Jérôme Mallefet, along with Hsuan-Ching Ho from the National Dong Hwa University, Taiwan, captured 27 adult, smalleye pygmy sharks from off the coast of Taiwan.

Further, they carried out an experimental analysis, under which they took skin samples of the shark and subjected it to various chemicals which were capable enough to enhance biological processes like light production. The samples were then tested as to how they responded towards the chemicals.

It was concluded that melatonin made their skin to glow under waters, but neurotransmitters, which standardized light emission under waters had no effect on the skin. Moreover, it was acknowledged that in the presence of the hormone prolactin, the glow faded.

Hence, it was suggested that the pygmy shark relied on the glow source only for misleading the predators or to hide, but they did not use the glow for communication.

However, in another species of shark dubbed lantern, prolactin showed other responses, it was able to produce a glow for almost 30-minutes, and it was used by the sharks for communication, whereas melatonin was used by them for a constant belly glow in camouflage.