“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.”
This passage has been cited as an anticipation of the idea of punctuated equilibrium.
Source: On the Origin of Species (1859), chapter IV: "Natural Selection", page 105 http://darwin-online.org.uk/content/frameset?pageseq=120&itemID=F373&viewtype=image
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Charles Darwin 161
British naturalist, author of "On the origin of species, by… 1809–1882Related quotes
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