Independent assortment is what causes humans to be different from each other. Humans actually share remarkably similar DNA. But, to answer your question, GENOME VARIATION are differences in the sequence in DNA, that vary from person to person.
The scientist that was consider to be known as the "Father of Modern Chemistry" is Antoine Lavoisier
Pollution :) Since Abiotic means non living.
Bacteria: Living
Food (worms or smaller fish): Living
Predators: Living
Pollution (dirt, trash, or other stuff): Non Living