First Living Organisms Help Introduction to the First Living
Organisms We will probably never know for sure exactly how life
began – Why? The first living things (such as primitive
bacteria) left behind no fossil record . Soft-bodied micro-
organisms, such as the ancient bacteria, had no hard parts.
Hence, their remains were rarely preserved. Fossil means “to
dig.” Thus, the fossil record consists of the remains of ancient
living things that have been preserved and “dug” up. With no
hard body parts preserved, then, the first living creatures
essentially left no fossils to be “dug” up later! Nevertheless,
many ancient soft-bodied bacteria created stromatolites (stroh-
MAT -uh- lights ) – “layered rocks.” Even today, huge mounds of
bacterial colonies live in shallow ocean water. Fine particles
of dirt, calcium, and other minerals in the seawater, collect as
sediment upon the colonies. This sediment eventually arranges
into thin “layers” ( stromas ) streaking through each bacterial
mound. As the layers or stromas