A followup from last week - Who could survive us?

As it was mentioned in my previous post, Earth's life will prevail; with or without us around. As it was gallantly displayed by George Carlin.
So, we would love to know "what" could survive us (besides the usual cockroaches that everyone believes invincible.

We can only survive for around 100 hours without water, yet there's a critter that is way more resilient than us, to the point that it can lack of water for decades. A 1 mm critter that is able to survive from the hottest to the coldest environments in our planet and radiation.

Source

The tardigrade, a real life Rambo -even if it looks like an overweight plush toy- is worthy of respect.
Many organisms have an imperative need for water to survive.Water is the main is the main tool that enables meta metabolism, the process that powers all our biochemical reactions in cells.

But, the tardigrade -AKA: water bear- bypasses this limit with a process: The anhydrobiosis (From the Greek: "life without water").

Tardigrades are Rambo, but there's also some other bad-asses that can "dry up" and survive. Bacteria, monocellular organisms named archaea, plants, and animals like the brine shrimp  or the roundworm.

This survival trait requires them to fold and constrict into a "tun". They fold themselves waiting for water to come back. As water becomes rare, tardigrades enter their tun state, they produce special glass-like molecules, that fill the tardigrade's cells to replace lost water by forming some nice crystals. Everything that is vulnerable to be dried (DNA, proteins, membranes) is enclosed in these crystal molecules.

This "freezes" the molecules preventing them from unfolding, breaking or merging. Once water is back, the crystals dissolve, leaving the sensitive parts unaffected by time and decay.

Tardigrades can tolerate a lot of stresses:

• High levels of radiation.
• Being frozen.
• Heated up past the boiling point of water.
• The vacuum of outer space.

This made some people speculate that they are not earthlings. It is a fun idea, but scientific studies place the origins well grounded in our planet -as any other species- it evolved here. They evolved so much, that we know more than one thousand species of them. They are everywhere. On every continent. On several biomes.

You don't need to go far to find some, you very probably have some in your yard or garden.

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Currently, tardigrades are being studied to find out if they use their tun state to cope with other kinds of stress.

If we can find out how they do freeze their biologic molecules, we may be able to use it to develop stress tolerant crops (because, we all know things don't grow as easy as they did 200 years ago... Thanks, climate change), stabilize vaccines.


Source

Meanwhile, tardigrades may answer a nice question: Who will survive us?