Hence, as more individuals are produced than can possibly survive, there must in every case be a struggle for existence, either one individual with another of the same species, or with the individuals of distinct species, or with the physical conditions of life.
Horregatik, bizirauteko modua izanen dutenak baino banako gehiago sortzen direnez gero, biziraupenaren aldeko borrokak gertatu behar, kasuaren arabera, espezie bereko kideen artean, edo beste espezie bateko banakoekin, edo bizi-baldintza fisikoekin.