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© Axel MauruszatDinosaur icons such as Diplodocus held their long necks high in the air not horizontally as previously thought
Did giant plant-eating dinosaurs such as Brachiosaurus and Diplodocus hold their long necks vertically or horizontally? In the long-running debate, the old-fashioned view that they held their heads up high is edging ahead.

Sauropods - stars of countless exhibitions, documentaries and books - have been depicted since the early 20th century with an upright posture. But doubt was cast on this when it was realised how hard their hearts would have to work to pump blood to their brains. Computer models of the vertebrae also suggested that the animals held their necks low. This led museums and film-makers to start showing sauropods grazing with necks stretched horizontally.

Now Mike Taylor at the University of Portsmouth, UK, and colleagues have studied the vertebrae of living animals to show that mammals and birds - the only groups to share the upright legs of dinosaurs - all hold their necks up. So Taylor reckons the computer models are wrong and sauropods, like their living counterparts, bent down only when necessary to feed (Acta Palaeontologica Polonica, vol 54, p 213). The debate doesn't seem set to end just yet, however. "It's never going to happen," admits Taylor.