Some structures are preserved in the fossil record more easily than others.

Some body structures are soft, like skin and muscle. Other structures are hard, like bones, teeth, shells and wood.

CLICK below to see what different hard and soft parts look like.

Organisms can be
mostly soft parts . . .

Or soft and
hard parts.

Which do you think are more likely to fossilize?

a) Hard body structures
b) Soft body structures

Correct!

Ooops!

Soft tissues are destroyed by physical and biological factors much more easily than hard structures. So even though we sometimes find fossils of soft-bodied organisms, they are much less common than fossils of hard structures. Try again . . .