When this creature faces deadly radiation, glowing is the only option
Posted October 19, 2020 4:19 a.m. EDT
CNN — Deadly levels of radiation won't stop this creature from shining bright.
This newly discovered strain of tardigrade can protect itself from lethal levels of ultraviolet light through glowing, according to a recent study published in The Royal Society journal.
The tardigrade found to have this trait is called the Paramacrobiotus BLR strain. It was first detected in Bangalore, India, on a concrete wall on a college campus, said study author Sandeep M. Eswarappa, who is an assistant professor at Indian Institute of Science.
Tardigrades, often called "water bears" or "moss piglets," are microscopic animals that are found in moist terrestrial and aquatic environments, according to Eswarappa. These critters, he explained, are closely related to worms and insects and are known to survive many conditions.
The 1-millimeter creatures can survive extremely harsh conditions, such as being frozen for 30 years and then resurrected.
Eswarappa became inspired to do the experiment after watching an episode of "Cosmos," hosted by Neil deGrasse Tyson.
"I decided to work on these creatures after hearing Dr. Tyson saying, 'The tardigrades have survived all five mass extinctions,'" Eswarappa said.
For the experiment, Eswarappa exposed this tardigrade along with another type of tardigrade, Hypsibius exemplaris, to UV light. All of the Paramacrobiotus tardigrades survived for 30 days after 15 minutes of exposure to the lethal rays. The other tardigrade died within 24 hours of exposure.
The hardy tardigrade was also the only specimen observed in the experiment to have glowed under the harsh light, which the researchers revealed was the key to their survival. The research team proposed that the tardigrade has a fluorescent shield that absorbs the harmful light and emits a harmless blue light, which is what causes them to glow.
The UV light used in the experiment is stronger than the UV light that reaches the Earth from the sun, which is the UV light most humans are familiar with. However, Eswarappa said he does not know if the UV light used in the experiment is the same as the UV light coming from the sun.
After discovering that their ability to glow was the tardigrades' secret weapon, Eswarappa made a fluorescent extract from the the Paramacrobiotus BLR strain and covered the other type of tardigrade used in the experiment in the protective material. When exposed to UV light, this enhanced tardigrade, which had originally died from exposure to the radiation after a day, showed partial tolerance.
Eswarappa said he plans to conduct additional experiments and possibly apply his discovery on a much larger scale. If synthesized in large amounts, the fluorescent extract made from the glowing tardigrade, he said, could potentially become a sunscreen for humans.