Answer:
The answer is A scientific theory
Explanation:
I just did it
Reptile scales! Or, more specifically, reptiles descended from dinosaurs.
While a constant supply of freshwater happens by itself in natural streams, an aquarium is by definition, a closed system. So here, man has to help out in order to provide new..
Oxygen is made and so is glucose (its actually sugar, but glucose is better sounding) by combining carbon dioxide and water using light energy as a source of energy. Also like to make sugars.
A bunch of the same critters. Nah I am just kidding, you will find a lack of resources because if they are all the same animals they will all eat the same thing. I hope this helps you.
