Last night I finished Chapter 2. Darwin writes about telling apart a species and its varieties and how difficult this can be. He makes two points in particular though that I want to quote.
... if we look at each species as a special act of creation there is no apparent reason why more varieties should occur in a group having many species, than in one having few.
In other words if g-d did all this why does it look evolved?
... when many species of a genus have been formed on an average many are still forming; and this certainly holds good.
Meaning evolution is still ongoing.
Just look at all these varieties of Oak Trees for example.