Because science is always changing and every time you cam come up with a new outcome.
Answer:
3 1 2
Explanation:
simple organisms apeared first insects would be less complicated than fish the came sharks as they are more complex organisms also insects were first to be food for fish and fish food for sharks
They get runoff into water sources which can be injested by fish which can be injested by birds or any animal who eats the fish or drinks the water including us!
Your liver might stop. Hope this helps