ABSTRACT
Although we do not always realize it, we live on a most remarkable ball of rock: of all the planets and moons in our solar system, Earth is (most probably) the only one which harbours life and quite possibly the only one which ever has. Why is that? The simple answer is that temperatures (and related conditions) on Earth are suitable for liquid water. However, that is not the full story of this planet. The vast diversity of life forms which we do call this Earth home is testament to the range of climatically habitable places for different ecosystems to be established.
