What If Tardigrades Are Alien Life Forms? | Unveiled
What If Tardigrades Are Alien Life Forms?
There’s remarkable diversity in life on Earth; in the living things that walk, crawl, swim, fly, grow and just generally exist in this world. But, sometimes, we find an animal that really looks like it didn’t evolve on this planet. And if there was ever a creature to which that applied, it would surely be the tardigrade.
This is Unveiled and today we’re answering the extraordinary question: What if tardigrades are alien life forms?
When examining most species on Earth, we can track its position on the evolutionary tree and see where some of its traits and abilities came from. Apes, chimps, dogs, cats, humans, and most animals all seem to “belong”, because it’s reasonably simple to see what came before them; to determine who or what their ancestors were, meaning we can understand why they’re like they are now. Certain creatures, though, force us to double take.
The octopus, for example, seems pretty alien to us. In fact, it’s said that no other animal is further from human beings on the tree of life. So much so that a 2018 study contributed to by thirty-three scientists around the world even came to the incredible conclusion that octopuses actually could be alien; the idea being that many of its features appear very suddenly in the history of life on Earth, without precedent on the evolutionary map. There are other animals, like the immortal jellyfish - which, as its name suggests, can potentially live forever - that have strange enough abilities that we might view them as “other-worldly”. Arguably, though, nothing can quite compare to the weirdness, uniqueness and sheer diversity of the abilities that are present in the tardigrade.
Tardigrades were first discovered in the 1770s, by the German zoologist Johann Goeze, who described them then as “little water bears”. In the years since, we’ve gradually learned more and more about what these amazing creatures can do. Though microscopic, tardigrades are probably the most resilient animal on the planet. They’re capable of living in almost any environment, having been found in (amongst other places) Japanese hot springs, across the icy plains of Antarctica, inside volcanoes, 18,000 feet above sea level in the Himalayas, and at the bottom of the ocean. They can survive extreme pressures and temperatures, including conditions just a few degrees above absolute zero, and they’re apparently impervious to radiation. Tardigrades can also live without food or water for decades if needed, slowing their metabolism to a state resembling death, before reviving themselves and rehydrating when the time is right. What might be even more incredible, though, is that (unlike everything else on Earth) these things can naturally survive the vacuum of outer space, and the females have even laid healthy eggs in space!
In many ways, then, they could be the perfect on-Earth candidate for a creature that also inhabits other worlds; an alien in our midst. And, like the octopus, the tardigrade does have further scientific backing to prove how strange it is… such as in 2015, when a team from the University of North Carolina at Chapel Hill sequenced its genome, finding that tardigrades have more “foreign” or “acquired” genes than any animal studied. So, how would the world react if this creature’s development was so unusual that it didn’t actually happen on Earth at all; if the tardigrade really was found to be alien?
The first questions would most likely be; where did it come from? And how did it get here? While we know that tardigrades can survive the vacuum of space, we’re only certain they can for short periods of time - with ten days being the longest stretch we know of. There’s a belief, though, that they’re capable of lasting for far longer. When, in April 2019, for example, an Israeli lunar lander carrying tardigrades crashed on the moon, there was mild panic at first. We had essentially accidentally just released Earth’s most resilient animals onto our closest neighbour - a very big misstep in terms of interplanetary contamination. That panic has since died down, and there’s no sign yet that the moon has become subject to a water bear empire, but the idea of tardigrades transporting through space hasn’t disappeared.
For some, it’s feasible that they could’ve arrived on Earth via an asteroid in the ancient past… especially because some species of tardigrade can reproduce asexually, meaning just one of them needs to have survived the trip. As for where specifically that asteroid might’ve come from, well, there’s no reason to think of any moon or planet or location as more or less likely than anywhere else. If it was ever proven that asteroids could be teeming with something like tardigrades at all, then that breakthrough will’ve already forced us to re-evaluate how we fundamentally view space in the first place. Suddenly, we’d know that space can host unassisted life indefinitely, and there’d be even greater enthusiasm to explore the solar system.
The oldest tardigrade fossils date back some 520 million years; so, imagine the social repercussions were we to suddenly discover that a hundreds of millions of years old alien race had been alongside us for all of human history… It’d be one of the biggest scientific breakthroughs of all time, and the tardigrade could become a genuine icon. Every biologist and alien researcher on the planet would focus on it, backed by probably more funding than ever before, prompting a “Tardigrade Effect” to ripple through science and pop culture. As in any hypothetical scenario where human beings prove alien life, it’d mean a total shift in how we view evolution, the universe and everything.
The search for alien life goes on, though, and suffice to say that tardigrades, as we understand them at this moment, are very much a product of Earth, only. They’re not alien, but because of their structural complexity, incredible abilities and unparalleled resistance, they have been labelled by some scientists as the perfect creature for space research. Crucially, they’re the only animal we know of that can survive in the vacuum of outer space so, alien or not, they could be vital in our ongoing research into space travel. Water bears are one of the most remarkable creatures out there, and certainly one of the most out-of-place species on the planet. But that’s what would happen if they turned out to be truly alien.
