I was born in Australia but grew up in England buy intagra Once-useful traits, however, can become worthless. Some can even become detrimental. That can happen if a species moves to a new environment â or if its environment changes. Now, a different trait, even one that might have been rare, can become more common. In this way, populations adapt to their environments. Biologists refer to this as natural selection. 必須 2000文字以内 [bbs:youtube:(Youtubeの動画ID)]と書くとYoutubeの動画が貼れます。(例:[bbs:youtube:OQThUAQ0UN0])