Scandinavia and the World

Comments #9675938:

Baby Daddy 2 9, 10:58pm

@Scanian_dreng comment about dogs had two points:
1) significant alteration of genetic population can happen within a relatively short timeframe. Even shorter, if you consider that temper of particular breed of dogs can change even faster
2) selection for only a small number of traits doesn't necessarily leads to superior breed or species overall. In case of dogs this effect is just more pronounced since selection is much stricter and sub-standard individuals are removed from breeding almost completely.

If you want an example of "go home, evolution, you're drunk", then take a look at Sacculina. Milder examples are sharks: ancient and ultimate predator that survived at least one extinction event turned out to be dumb as a bag of rocks, especially when compared with killer whales.