Tardigrades – The Ultimate Survivors?

What are tardigrades? And where are they?

Tardigrades, also known as water bears or moss piglets, can be found all over the world. There are over a 1000 known species, but they share some unique features. They have eight little stubby legs with claws and are not the most agile or swift moving. In fact, their original name stems from the Latin ‘tardigradus’ meaning ‘slow stepping’. They have a head full of muscles that they use to suck up food, and a mouth (that at first glance looks a bit like a snout) that earned them the nickname ‘moss piglets’. Different species of tardigrades have different food preferences, some are completely herbivorous (only eat plant matter), some are omnivorous (eat both plants and other small creatures), and some will even eat other tardigrades! They are very small relative to other animals, approximately 0.05 to 1.2 millimetres, meaning you usually need a microscope to see them. However, if you look closely enough you may be able to see a large one without a microscope.

They live in a range of different environments – from the tops of mountains to the deep sea, from steamy hot springs to the frozen icy poles. But they do not just live in extreme environments, they are likely to be right near you at this very moment - just outside in your garden, local park, on a nearby tree or even a patch of moss on your building.

So, what do they have to do with space?

Whilst they do not naturally live in space (that we know of!), they were the first Earth-dwelling species discovered to survive in space with absolutely no protection! They have been proven to survive exposure to space conditions for 10 days, in comparison, it is predicted a human could only survive for no more than two minutes in space conditions without protection.

What is the source of their superpowers?

So, where did these abilities come from? Were they bitten by a radioactive spider, or did they discover a mysterious alien item from another planet?

It turns out they are born with their gifts – and the secrets can be found in their DNA. Tardigrades, like all animals on Earth (including us humans), contain the information in their cells of what their abilities can be. Unfortunately, our cells are not coded to develop wings like a bird or breathe underwater like a fish. However, tardigrades are coded to have extraordinary powers. Interestingly, different species of tardigrades have different conditioning and extents to their powers. We do not fully understand why this species has evolved to become so tough and robust, but some scientists believe the reason is to ensure their survival in unpredictable environments, like moss. Moss can be quite an unpredictable habitat to live in, as it can dry out for long periods of time or be so wet that it becomes more of an aqueous habitat.

Can They Help Us In Space Exploration?

So how are these creatures going to help us survive in space? The creation of a new human – tardigrade mutant? Actually, that may not sound as ridiculous as you may think. In a study led by Takuma Hashimoto, Daiki Horikawa and Takekazu Kunieda at the University of Tokyo, tardigrade proteins that help suppress damage caused by X-rays were transferrable to human cells. Time will tell what the future holds; perhaps these creatures will be the key to our survival in space, maybe with some help from a tardigrade protein bar (okay – maybe not in a protein bar)!