There is grandeur in this view of life, with its several powers, having been originally breathed into a few forms or into one; and that, whilst this planet has gone cycling 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.

Lastly, isolation, by checking immigration and consequently competition, will give time for any new variety to be slowly improved; and this may sometimes be of…

As many more individuals of each species are born than can possibly survive; and as, consequently, there is a frequently recurring struggle for existence, it f…

One general law, leading to the advancement of all organic beings, namely, multiply, vary, let the strongest live and the weakest die.