You’ll Never Believe What These Tiny Creatures Can Do

Tardigrades or “Water Bears”  live in water.  They are segmented micro-animals with eight legs and can survive in extreme conditions, even in those detrimental to most life on earth.  They are the only living animals known to be able to survive the extreme conditions in the vacuum of outer space.

A water bear (Paramacrobiotus craterlaki).

Tardigrades are usually around 0.5 mm (0.020 in) long when they are fully grown, so you might need a powerful magnifying glass or a low power microscope to observe these fascinating creatures.

Tardigrades can withstand extreme temperatures, from just slightly above absolute zero to well above water’s boiling point.

They are short and plump with four pairs of legs, each of which has four to eight claws, known as ‘disks’.


Tardigrades can withstand pressures of about six times stronger than water pressures in the deepest ocean trenches.  They can survive ionizing radiation at doses hundreds of times higher than the lethal dose for a human being, and the vacuum of outer space.

These creatures can be found in mosses and lichens.  They feed on algae, plant cells, and small invertebrates.

There are over 1,150 different species of these beautiful creatures.

Tardigrades are ancient animals, with fossils found dating from 530 million years ago.