Quote Originally Posted by Wayfaerer View Post
This observation rests on a dynamical process that changes dramatically with time, natural selection. If some environmental factor starts killing off white swans while brown swans stay camouflaged or something, swans will normally be brown while some mutations may be blue and purple, or eventually turn into a completely different species that climbs trees or something lol
Yes, evolution takes longer than our lifetime though. And if it started changing, we'd observe that, figure out how fast it's changing and determine at what point all swans would be brown. And probably keep a few white ones in a zoo