No sex please, we’re condors

FEW ANIMALS have come closer to extinction, and yet survived, than the Californian condor. Thousands died as a result of flying into electrical cables or being poisoned by lead shot from discarded game-animal carcasses. By 1982, there were only 22 left. These relicts were rounded up and brought into a captive-breeding programme that proved an astonishing success. Thanks to the efforts of a team of conservationists co-ordinated by the San Diego Zoo Wildlife Alliance there are now 329 condors flying freely in western North America, and 175 more in the care of various zoos.As the precision of those numbers suggests, these birds are among the most closely monitored in the world. It therefore came as a shock to Oliver Ryder, a geneticist at the alliance, when he discovered that two of the females he was scrutinising had laid eggs unfertilised by males, which then went on to hatch.