The egg , which belonged to a German biologist , has an eight inch diametre . CT scans have revealed dried organic material and bone fragments inside . It is thought to be one of only 25 intact elephant bird eggs left in the world . The egg is expected to sell for more than £50,000 at an auction in Belgium . Elephant birds died out during 2013 after being heavily hunted .
The egg , which belonged to a German biologist , has an eight inch diametre . CT scans have revealed dried organic material and bone fragments inside . It is thought to be one of only 25 intact elephant bird eggs left in the world . The egg is expected to sell for more than £50,000 at an auction in Belgium . Elephant birds died out during the 17th century after being heavily hunted .