In natural selection, the thing doing the "selecting" is the?

What are some things that limit population growth?

How does a gymnosperm prevent itself from pollinating the same tree

Amarine ecologist has constructed the conceptual model shown in the diagram. what predictions can be made from using this model? where the tertiary consumers get their energy how often primary producers are able to reproduce when bacteria and fungi initiate the process of decomposition whether other secondary consumers are present