"When on board H.M.S. Beagle, as naturalist, I was much struck with certain facts in the distribution of the inhabitan…"

"As many more individuals of each species are born than can possibly survive; and as, consequently, there is a frequen…"

"Although much remains obscure, and will long remain obscure, ... I am convinced that Natural Selection has been the m…"

"When we look to the individuals of the same variety or sub-variety of our older cultivated plants and animals, one of…"

"Pigeons can be mated for life, and this is a great convenience to the fancier, for thus many races may be kept true, …"

"[I]t will be seen that I look at the term species, as one arbitrarily given for the sake of convenience to a set of i…"

"Owing to this struggle for life, any variation, however slight and from whatever cause proceeding, if it be in any de…"

"We will now discuss in a little more detail the struggle for existence."

"We behold the face of nature bright with gladness, we often see superabundance of food; we do not see, or we forget, …"

"As buds give rise by growth to fresh buds, and these, if vigorous, branch out and overtop on all sides many a feebler…"