In the event that Earth is struck by an asteroid, the sun goes supernova or the planet is soaked in gamma ray bursts in an extreme energetic explosion, the last surviving creatures won’t be cockroaches – they will be tardigrades. Oxford University researchers recently discovered this after exposing the microscopic water bears to the only astrophysical phenomena likely to eradicate life on Earth. Not only did the team learn that the tardigrade can endure temperature extremes of up to 150°C (302°F), they discovered that the eight-legged animals can resist radiation levels of 5000 to 6200 Gy (around the dose used in some forms of chemotherapy), making them the most indestructible creatures on this rock.
Dr. Rafael Alves Batista, a researcher at the department of physics at Oxford University, told the Daily Mail that the goal was to “study what is necessary to kill all life, not just humans. Batista added that the scientists were pleasantly surprised to learn that the water bear is incredibly resilient to most threats. Co-author of the study, Dr. David Sloan, wrote: “To our surprise, we found that although nearby supernovae or large asteroid impacts would be catastrophic for people, tardigrades could be unaffected. Therefore it seems that life, once it gets going, is hard to wipe out entirely.”
Unlike humans, the tardigrade is extremely durable. As previously mentioned, the animals are resistant to high levels of radiation and can endure astronomically high temperatures. Additionally, the water bears were once frozen for thirty years, thawed out and were found to still be alive. Said Batista, “Without our technology protecting us, humans are a very sensitive species. Life on this planet can continue long after humans are gone.” As a result of the findings, the researchers concluded that the water bears could live on Earth for at least ten billion years and would only be wiped out when the sun exploded. “Huge numbers of species, or even entire genera may become extinct, but life as a whole will go on,” said Sloan.
Some are unsurprised by the water bear’s hardiness, considering Russia found the species clinging to the International Space Station — alive — even while exposed to the vacuum of space. Regardless, the finding is exciting for scientists who desire to find life on other planets. Said Batista, “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. If Tardigrades are Earth’s most resilient species, who knows what else is out there. There might exist other creatures similar to tardigrade in other places. We have to keep searching.”