Alphonse de Candolle and others have shown that plants which have very wide ranges generally present varieties; and this might have been expected, as they are exposed to diverse physical conditions, and as they come into competition (which, as we shall hereafter see, is a far more important circumstance) with different sets of organic beings.
Alphonse de Candollek eta beste batzuek zabal hedaturiko landareek eskuarki aldakiak erakusten dituztela frogatu dute. Hau espero izatekoa zen kontuan izanik baldintza fisiko ezberdinen pean bizi eta izaki organikoen multzo ezberdinekin lehian ari beharra dutela, zirkunstantzia hau, gero ikusiko dugun bezala, bestea bezain garrantzitsua edo garrantzitsuagoa delarik.