Erasmus Darwin was Charles Darwin's grandfather. See http://en.wikipedia.org/wiki/Erasmus_Darwin
Charles Darwin did not "come up" with evolution. Evolution always existed, and Darwin rather eloquently explained one theory (or a number of theories, depending on how you read his work) on how...
By watching different animals in different places of the world.
Mount House, ShrewsBury, Shropshire England!
Nether=below The Netherlands are mostly below sea level.