The Toughest Animals in the World

Everyone says that after the nuclear holocaust, the only animals left on earth would be cockroaches. I have no idea whether cockroaches would survive, but there is a pretty good chance that these fellows would.

Tardigrade

Water Bear

 

 

 

 

 

 

Tardigrades, also known as ‘water bears’

grow only to a size of about 1mm, but they can easily be seen with a microscope. Tardigrade bodies are short, plump, and contain four pairs of lobopodial limbs (poorly articulated limbs which are typical of soft bodied animals). Each limb terminates in four to eight claws or discs. They lumber about in a slow bear-like gait over sand grains or pieces of plant material.

A few years ago, a team from Sweden and Germany, led by Ingemar Jönsson, developed a program called TARDIS (geeks), where they sent tardigrades into space to see how they would fare. (I’m slow, they published in 2008)

The reason they tried this is because

They also happen to be nigh-invincible and can tolerate extreme environments that would kill almost any other animal. They can take temperatures close to absolute zero, punishing doses of radiation and prolonged periods of drought. And now, they have become the only animals to have ever survived the raw vacuum of space…

The tardigrades were sent into orbit in a dry, dormant state called a “tun” and it’s this dessicated form that is the key to their extraordinary levels of endurance. By replaceing almost of the water in their bodies with a sugar called trehalose, they can escape many of the things that would otherwise kill them.

The results were almost unbelievable.

The majority of both species made it through the vacuum of space and the accompanying cosmic radiation, and were just as likely to still be alive as tardigrades that had remained on the planet. They even managed to lay viable eggs that hatched just as well as their planet-bound peers. Even the eggs themselves shrugged off the inhospitable conditions of space.

However, Jonsson did find a limit to their endurance – they struggled to cope with a combination of space vacuum and the high doses of ultraviolet radiation given off by the sun. If their containers were unshielded by UV filters, most of them died as the powerful radiation shattered their DNA.

But not all of them. Even faced with these harshest of conditions, a small number of hardcases survived.

Minute interplanetary travelers. I wonder how Kirk would have fared having Trouble with Tardigrades.

Even an old crank like me can still be amazed.

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