## Did you know that...

...Tardigrades, also known as water bears, were first described in 1773 (Figure 20.12). These microscopic animals are surprisingly cute when observed under the microscope and are quite interesting to study. Tardigrades have been shown to survive at very cold temperatures (down to -273o C) and at very hot temperatures of 150o C – that is hotter than boiling water!! It is possible that these cute little water bears have been on Earth for over 600 millions years – before the dinosaurs. Know, scientists are using the amazing ability of tardigrades to survive space radiation as a model organism in astrobiological studies. Read more about tardigrades as a model organism here.