But the best evidence of analogous variations is afforded by parts or organs which are generally constant in character, but which occasionally vary so as to resemble, in some degree, the same part or organ in an allied species.
Baina aldakuntza analogoen frogarik onena honako organo edo atal hauek dakarkigute, alegia, eskuarki iraunkorrak diren baina batzuetan espezie hurbil baten organo edo atal berdinen antzekoak graduren batean izateraino aldatzen direnak.