Humans

In the seventy thousand years that modern human beings have walked this earth, we've come a long way. Art, science, culture, trade - on the evolutionary food chain, we're real winners. But, frankly, it's not exactly been plain sailing, and sometimes - just occasionally - we've managed to really, truly, quite unbelievably f*ck things up.
From Chairman Mao's Four Pests Campaign, to the American Dustbowl; from the Austrian army attacking itself one drunken night, to the world's leading superpower electing a reality TV mogul as President... it's pretty safe to say that, as a species, we haven't exactly grown wiser with age.