If humanity were to disappear from the face of the earth tomorrow, what would happen? That’s the interesting conceit explored by science writer Alan Weisman in his new book, The World Without Us (to be release next month). Scientific American interviewed Weisman and features his book on their website this week.
It is a fascinating idea that I’ve read about before. How long would it take our artifacts to disappear? In the case of the more obvious stuff like buildings, bridges and roads, only a few decades are required before nature reclaims the landscape. More insidious things last longer. Plastics could take thousands of years to degrade, while carbon dioxide levels in the atmosphere would take a hundred thousand years to return to levels prior to the industrial revolution. Pollution in the soil could well take a million years to dissipate, and the uranium 235 found in nuclear reactors would take only 700 million years to decay into lead.
So who would miss us? Definitely head lice; they couldn’t survive without us. And domesticated livestock and crops wouldn’t fair too well either. Interestingly, the ubiquitous cockroach would suffer in our absence as well. Without warm homes to inhabit with ready food supplies, the cockroach would disappear from temperate climates during the frigid winters.
On a related note, check out these images of a ruined Tokyo, destitute of humanity and crumbling back into the earth. Cool stuff.