Answer:
riding the bike instead of the Car
There were two approaches for the planetary paths. The idea about the planets revolving around the Earth, the planetary paths were plotted and were erratic. It was not relevant to the laws of motion and gravity. That fact was neglected by the believers in an Earth-centered Solar System.
Sun-centered Solar System was theorized by Copernicus. The paths assumed to be relatively circular (or elliptical).
I think if the whale population decreased the surface fish populations would decline due to reduced populations of algae. This can be simply explained by the fact that, if the whale population is decreased, it means that the nitrogen rich feces that is supply nutrients to the algae would also decrease and therefore decrease the population of the algae and as a result the population of of the surface fish would also decline.
