But, as we have seen, organic beings long habituated to certain uniform conditions under a state of nature, when subjected, as under confinement, to a considerable change in their conditions, very frequently are rendered more or less sterile;
Baina, ikusi dugun moduan, natur egoeran zenbait baldintza uniformetara luzaz ohituriko izaki organikoak, beren baldintzetan, hesiperatzean gertatzen den moduan, aldaketa asko ezartzen bazaizkie, beti ere antzu bihurtzen dira gutxi-asko;