It is interesting to contemplate an entangled bank, clothed with many plants of many kinds, with birds singing on the bushes, insects flitting about and worms crawling through the damp earth, and to reflect that these forms, so different yet so dependent on each other in so complex a manner, have all been produced by simple laws.There is grandeur in this view of life, with its several powers, having been originally breathed by the Creator into a few forms or into one; and that, whilst this planet has gone circling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being evolved.

Charles Darwin, from 'On The Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life'