Tardigrades, often affectionately called water bears or moss piglets, are some of the most fascinating and resilient creatures on Earth. Measuring less than a millimeter in length, these microscopic animals have captured the attention of scientists and science enthusiasts alike due to their almost supernatural ability to survive extreme conditions.
Tardigrades are eight-legged micro-animals belonging to the phylum Tardigrada. First discovered in 1773 by German zoologist Johann August Ephraim Goeze, they were later named “Tardigrada” (Latin for “slow stepper”) by Italian biologist Lazzaro Spallanzani in 1777. They inhabit a wide range of environments—from deep sea trenches and high mountain peaks to arid deserts and the icy Antarctic.
Tardigrades are everywhere. You’ll find them in:
All they need is a thin layer of water to stay active. When water is scarce, they have a remarkable trick up their sleeve.
One of the reasons tardigrades are so famous is their ability to enter a state called cryptobiosis. In this near-death state, they:
In this form, tardigrades can survive:
They essentially shut down until conditions improve—then spring back to life like nothing happened.
Yes! In 2007, tardigrades became the first animals to survive in outer space without any protection. Sent aboard the European Space Agency’s FOTON-M3 mission, some tardigrades not only survived the vacuum and radiation of space but also reproduced afterward. This amazing feat has made them central to astrobiology research and theories about life surviving in extreme extraterrestrial environments.
Tardigrades are more than a curiosity:
Not exactly. While they can survive extreme conditions for years, once they’re active again, their life spans are typically a few months to a couple of years depending on the species and environment. Their ability to pause life, though, means they can outlast most organisms in the long run.
Nope. Tardigrades are harmless to humans. They feed on fluids from plant cells, algae, or small invertebrates. Despite their appearance, they’re not parasites or threats.
Tardigrades may be tiny, but they’re titans when it comes to survival. These ancient, nearly indestructible creatures remind us that strength doesn’t always come in size—it can come in adaptability, evolution, and an unbreakable will to live. Whether as keys to future space exploration or models of biological resilience, tardigrades have more than earned their nickname: Nature’s Toughest Survivors.