How should I deal with these DB entities when using OOP?

Say I have this ER Diagram

How should I proceed when creating the classes? Should I create a Species class with a list of Breeds, or a Breed class with a Species attribute? I don't know yet how the business logic will unfold, but I assume that I'll have to deal with both situations: I may have to retrieve a list of all Breeds belonging to a Species, or the Species to which a Breed belongs.

I know there is not a single answer to this, but any pointer in the right direction would be appreciated.