But fierce bidding broke out at Christie's for the partly-fossilised specimen, laid by an elephant bird, which is now extinct. In terms of scale, it's estimated to be 100 times the size of a normal egg.
Egged onOne of the reasons why the egg sold for the best part of £70,000 was that intact examples are rare. The flightless elephant bird - the largest bird ever to have lived and found in Madagascar between the 15th and 17th centuries - was related to emus and ostriches, but eventually hunted to extinction, partly because of its enormous size, up to 11 feet high.
Marco Polo had even been sent by the Great Khan to track down the huge birds. The Mail claims David Attenborough owns a nearly complete eggshell, pieced together from a trip in 1961 to make the BBC series Zoo Quest to Madagascar, though he revisited the island to make another documentary in 2011.
IntactIt's also thought that scavenging rats and dogs - almost certainly bought to the island by humans - also played their part in the extinction of the bird. An intact example of an elephant bird's egg can be seen at the Delaware Museum of Natural History; London's Natural History Museum also has an example.
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