The most amazing life on Earth is invisible to the naked eye. The water bear, or tardigrade, is less than a millimeter in length but it has a survival record that would make any other animal blush. Whether it is hot or cold or in the deep space, this little creature has demonstrated its ability to survive in conditions that no other life form can.
So What is a Tardigrade?
Tardigrades are micro-animals that were discovered in the 18th century and survive in water films on moss, soil, or marine environments. They resemble miniature gummy bears with eight short legs, and although they may not look very impressive, they are biological miracles. Tardigrades are neither insects nor are they related to any other familiar animal group. They create their own phylum Tardigrada, and their survival capabilities are unsurpassed in the animal kingdom.
What Makes Them Practically Indestructible?
Tardigrades have been found to survive in extreme temperatures, including temperatures nearly as low as absolute zero, and above 150° C. They have survived huge quantities of radiation, pressures that exist far beneath the ocean floor, total dehydration over decades, and even the vacuum of space.
They do this by going into a state known as cryptobiosis, which basically means they stop all biological processes. Here they dry up and curl into a hardened ball called a tun. They have a sugar-based shield and special proteins that stabilize their DNA and inhibit internal damage, even under the most severe conditions.
The Day They Went to Space
In 2007, tardigrades entered history by being launched into space by the European Space Agency in the FOTON-M3 mission. These animals were subjected to the vacuum of space and raw solar radiation. By the time they were recovered, a large number of them had survived, and some even reproduced. This made tardigrades the first animal to survive space exposure without protection suit or environment, and placed them squarely on the astrobiology map.
In 2019, a privately developed Israeli lunar lander crash-landed on the Moon with a cargo of dehydrated tardigrades. Although it is not clear whether they survived the impact, their presence up there has created curiosity all over the world. Although tardigrades do not actively flourish in space, their resilience to such harsh environments has led scientists to include them when discussing the theory of panspermia, which proposes that life can be transferred between planets by asteroids or spacecraft.
Tardigrades could be the best candidates to hitchhike through the universe.
Tardigrades are not mere curiosities; they are a biological blueprint of resilience. Their survival strategies may lead to new technologies, provide insight into how life may exist elsewhere in the universe and even be used to preserve cells and DNA to use in space travel or medicine.
They have also captured the imagination of people. Not many creatures can glow under UV light, be frozen solid, and survive cosmic radiation, and look like a cartoon bear in another dimension.
Fun Facts About Tardigrades
- 🐾 They’re not insects, and they’re not related to bears — but they’re just as tough.
- ✨ Some species glow under UV light to resist radiation.
- 🔫 They’ve survived being shot out of a gun at 900 m/s.
- 🌕 There may be tardigrades on the Moon right now.
Final Thoughts
The tardigrade is one of nature’s most fascinating oddities — a microscopic, chubby-legged creature that has redefined what it means to be “alive.” Whether it’s surviving in volcanic vents or floating through the vacuum of space, the tardigrade is living proof that life can be tougher than fiction.
In a world of climate extremes and space exploration, this tiny survivor might just be a biological blueprint for life beyond Earth.
