An extremophile is an organism that can live and thrive in extreme in environments such as extreme temperatures, pH levels, or radiation. One example of an extremophile are organisms called tardigrades, also known as water bears. Over 1,300 species of tardigrades are found throughout the world.
These microscopic organisms are considered to be aquatic due to the need of a thin layer of water around their bodies in order to prevent dehydration. Tardigrades are eight legged organisms that have six claws on each foot. Tardigrades have a thick cuticle similar to the exoskeletons of some insects, and it sheds in order for them to grow.
Tardigrades are very resistant to extreme environments. They can survive temperatures as cold as -273.15°C and can survive boiling temperatures. They can also go up to thirty years without food or water and can also survive extreme pressure environments such as deep ocean or outer space. They can do this because they have special proteins in their bodies that protect their DNA.
They can also survive extreme environments through a state of cryptobiosis, in which they squeeze water out of their bodies and retract their limbs and head in order to go into a balled-up state. They can produce sexually or asexually which helps the continued survival of the species. Due to all these factors, tardigrades can survive and reproduce in extreme environments making them quite interesting organisms.
