The Nature of Technology (Free Press, 2009) are suffused with concepts from natural selection, as is my own, The Rational Optimist (Fourth Estate, 2010). Tim Harford's Adapt follows this tradition, focusing on the key role of failure - the 'error' in trial and error - in economic and social progress. Oxfam's chief executive, Dame Barbara Stocking, claimed this week in a BBC interview that there will "absolutely not be enough food" to feed the world's population in a few decades' time. Such certainty about the future is remarkable, so I downloaded Oxfam's new "report" with interest. Once I got past the fundraising banners, I found a series of assertions that there is a food crisis caused by failures of government "to regulate, to correct, to protect, to resist, to invest, which means that companies, interest groups and elites are able to plunder resources and to redirect flows of finance, knowledge, and food". Oxfam is calling for "a new global governance" - effectively the nationalisation of the world food system. A recent paper in the journal Nature concluded that species extinction caused by habitat loss is happening less than half as fast as usually estimated. The normal method for calculating rates of extinction assumes that doomed species merely cling temporarily to a shrunken patch of habitat, on their way to disappearing (an idea called "extinction debt"). Apparently, this isn't the case: Although a larger patch of habitat has more species in it, shrinking a patch does not lead to a proportional