Extinction and "survival of the fittest" (the latter a gloss put on Darwin's notions that he didn't coin himself and was reluctant to embrace) have nothing to do with each other. Species become extinct; natural selection does not "weed out poorly-adapted species" but leads to differential survival of heritable traits within species.This confusion, intentional or otherwise, is in danger of bringing superb science into disrepute, a process deliberately embarked on by idiots such as pete and his dishonest ilk and unfortunately promoted by third-rate "popular science" writing.