<p>Veteran environmental journalist Fred Pearce used to think of invasive species as evil interlopers spoiling pristine 'natural' ecosystems. Most conservationists would agree. But what if traditional ecology is wrong, and true environmentalists should be applauding the invaders?<br><br>In The New Wild, Pearce goes on a journey to rediscover what conservation should really be about. He explores ecosystems from Pacific islands to the Australian ou...