Biosystematics is the classification of different forms of life.
Viruses are not considered “living”; yet bacteria is.
Why?
Principle 1: Life is Determined by Ability to Replicate Independently
Humans, bacteria, fungus, and even grass can all create more of itself through a process called reproduction.
However, a virus cannot reproduce without depending on the machinery of another organism called its host. Therefore, for a virus to be successful, it needs to always infect some other organism, making viruses contagious.
Principle 2: Taxonomy is the Classification of Living Organisms
What makes a dog a dog? Why are there so many different types of dogs? What makes one type of dog different from the other?
Are humans related to monkeys? How closely related are we? Can we consider humans to just be another type of ape?