What is one way to classify mud found in an ecosystem?
A) organism
B) population
C) biotic factor
D) abiotic factor
Mud is (D), an abiotic factor on edge.
Answer:
The most recent common ancestor of all currently living organisms is the last universal ancestor, which lived about 3.9 billion years ago. ... 6,331 groups of genes common to all living animals have been identified; these may have arisen from a single common ancestor that lived 650 million years ago in the Precambrian.