We have reason to believe that species in a state of nature are closely limited in their ranges by the competition of other organic beings quite as much as, or more than, by adaptation to particular climates.
Badugu arrazoirik uste izateko beste izaki organikoen norgehiagoketak natur egoerako landareak bizi diren herrialdeetara hertsiki mugaturik dituela, klima konkretuetara ekandu beharrak bezainbat edo honek baino gehiago.