Answer:
Faunal Succession
Explanation:
The scientific principle that assumes that the different forms of animals throughout the Earths past occurred in a definite order is called the principle of faunal succession.
This principle determines that fossil organisms follow one another
in a definite, irreversible time sequence.
Fossil communities change through time as some species become extinct and new ones appear.
The principle was first recognized at the beginning of the 19th century by William Smith.
