M. Perrier found that their exposure to the dry air of a room for only a single night was fatal to them. On the other hand he kept several large worm… - Charles Darwin

It is always advisable to perceive clearly our ignorance.

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 importance in the production of new species. If, however, an isolated area be very small, either from being surrounded by barriers, or from having very peculiar physical conditions, the total number of the individuals supported on it will necessarily be very small; and fewness of individuals will greatly retard the production of new species through natural selection, by decreasing the chance of the appearance of favourable variations.

Mr. Darwin begs me to say that he receives so many letters that he cannot answer them all. He considers that the theory of evolution is quite compatible with the belief in a God; but that you must remember that different persons have different definitions of what they mean by God.