1.   For example, biologists have been searching ancient Earth rocks for traces of fossilized ancient microbes resembling those found in the Mars rock.

2.   His energy institute is centered on a group of ancient microbes, archea, which inhabit the deepest parts of the earth and ocean.

3.   Peaceful coexistence, even coevolution, is the rule between the ancient ubiquitous microbes and the human arrivistes.

4.   The genetic analysis of an ancient microbe revealed secrets about how the tree of life is organized.