I ask this question in relation to the origin of life. I realise it would probably be better suited to a geology stack exchange, but it does not yet exist. The Miller-Urey experiment gives a lab ...
Reading one of Sir Arthur Clarke's scifi stories, I came across a statement something to the effect of, existence of a single species automatically implies the existence of many other species. So ...
I know from school, that all live on the Earth need bacteria as low-level "machines" that break down/extract/convert/produce chemical elements and combinations, other high-level organisms needed. But ...