A tree of cellular life

Most of the branches on this version of the Tree of Life show microscopic organisms, and it doesn't even include the bacteria and viruses. Many of these organisms are so small that they cannot be seen by the naked eye.

Animals only occupy one small branch in the bottom left hand corner of the tree.

Many people think mostly about animals, particularly mammals, when they consider Earth’s biodiversity. However, the vast majority of organisms on Earth are microscopic. These species are essential for the survival of life on Earth and many of the natural processes that we rely on, like decomposition, would not take place without them.

Any complete Tree of Life, showing the Earth’s organisms, is made up mostly of microscopic species.

Cartoon image of footprints leading through closing door

Our scientists study the snails that host the schistosomiasis parasite, which causes a disease that affects nearly 200 million people.