FOSSIL CLUES

I have just finished reading AG 129 and would like to congratulate palaeontologist Dr Phil Bell on his refusal to give the dinosaur ‘Lightning Claw’ an official name. It amazes me that based on “a giant claw...parts of the arm, hip and foot; pieces of ribs and a whole bunch of other fragments” palaeontologists are able to build up a picture of the sleek animal your artist has given us. Nothing was mentioned of jaw bones, yet this creature “lacked the powerful jaws of other carnivores”. Sorry, but how do we know that? Yet we have a beautiful dinosaur, with jaws and colouring that are surely an artist’s conception, hailed as Australia’s biggest carnivore. Palaeontologists have great imaginations! But well done, Phil – hold back until more fragments come your way. DEREK WATSON, JINDABYNE, NSW

Dr Phil Bell, of the University of New England, says: Reconstructing extinct animals is not easy, but nor is it impossible. An expert would not mistake a snake vertebra for that of a lizard, and they would also be able to reconstruct that animal, based on one or two bones, with a relative degree of certainty based on what they know about complete skeletons of its close relatives. The same is true for dinosaurs. Thus, from a few scraps, Lightning Claw can be identified as a carnivorous dinosaur belonging to the family Megaraptoridae. More complete megaraptorid skeletons are known from South America and we can use those to fill in the gaps. Ultimately, these are best-guess scenarios and the whole truth will only be known when a complete skeleton of Lightning Claw is found.