redsockfan  

So how do these words relate?

These are animals in the energy pyramid, the energy pyramid is what shows how energy travels throught the ecosytem.

Whats an ecosystem?

It's setup of communities and populations in a habbitat .

So what are comunities, population, and habbitats?

Populations are a group of a specific organisms. While a comunity is all the populations in an area. Then a habitat is how the community and the abiotic features interact.