LONDON — A new study has revealed which form of life is most likely to outlast all others on Earth.
Researchers from Oxford University and Harvard University determined that the tardigrade will likely hold the honor of being the world’s final survivor. A tardigrade, commonly referred to as a “water bear,” is a tiny, eight-legged micro-animal. They are generally found in water, and reach just a microscopic 0.5 millimeters in size.
The research indicates that water bears will continue to exist until the sun eventually dies out, what scientists predict to be another 5 to 10 billion years. Tardigrades are the most resilient creature known on Earth, withstanding temperatures of up to 300 degrees Fahrenheit. They are also sufficiently low-maintenance, capable of surviving for 30 years without anything to eat or drink.
In the study, the researchers hypothesize astrophysical catastrophes that could boil all the oceans on the Earth – the only methods that could potentially eliminate water bears from the planet to deem them extinct. The three major catastrophes that the researchers considered effective were asteroid impact, supernovae, and gamma-ray bursts.
Because of the impracticality of those events, the researchers determined that water bears will simply exist throughout the lifespan of our sun. This is far longer than any other species on Earth is expected to survive.
Co-author David Sloan, a post-doctoral researcher at Oxford University’s Department of Physics, explains how this study is relevant to finding life throughout our neighboring planets and solar systems.
“A lot of previous work has focused on ‘doomsday’ scenarios on Earth – astrophysical events like supernovae that could wipe out the human race,” says Sloan in a university news release. “Our study instead considered the hardiest species – the tardigrade. As we are now entering a stage of astronomy where we have seen exoplanets and are hoping to soon perform spectroscopy, looking for signatures of life, we should try to see just how fragile the hardiest life is.”
Co-author Dr. Rafael Alves Batista argues that while tardigrades may be the strongest organisms on the planet, there may be other species similar to its stature outside Earth.
“Tardigrades are as close to indestructible as it gets on Earth, but it is possible that there are other resilient species examples elsewhere in the universe,” says Batista. “In this context there is a real case for looking for life on Mars and in other areas of the solar system in general. If tardigrades are Earth’s most resilient species, who knows what else is out there.”
The full results of the study were published this month in the journal Scientific Reports.