All animals cannot make their own food, they are consumer
Translation is the process by which a protein is synthesized from the information contained in a molecule of messenger RNA (mRNA). ... Translation occurs in a structure called the ribosome, which is a factory for the synthesis of proteins. -google
Clues such as fossils such as bones, footprints, tar, etc, preserved underground helped inform scientists. You can also count how old a tree is when you cut it open and there are some alive for thousands of years so that is a possible way.
Answer:
first it start from small atoms and change slow
