Museums and TV have dinosaurs' posture all wrong, claim scientists

Photograph: Getty

The popular depiction of sauropod dinosaurs such as Camarasaurus, above, as lumbering creatures with outstretched necks may be wrong. 

The staid and scholarly world of palaeontology was thrown into rare turmoil yesterday following the latest salvo in an argument that dates back to Jurassic times.

The row erupted after a team of British fossil experts published a fresh analysis of animal bones in an arcane academic journal. In their paper they challenge a view of dinosaurs that is so familiar it has almost become the accepted truth.

The controversy goes to the heart of our perception of the largest of the dinosaurs, the sauropods, which became widespread 150m years ago in the late Jurassic. According to the researchers, the beasts did not stick their necks out in front of them as so often depicted, but held their heads high on majestic, curving, swan-like necks.

The claim overturns the popular impression of the lumbering creatures given by museum exhibits and TV series like the BBC's Walking with Dinosaurs. The sauropods include many of the most well known prehistoric beasts, such as diplodocus and apatosaurus, the dinosaur formerly known as brontosaurus. Some sauropods were more than 40m long and weighed over 100 tonnes.

"Unless sauropods carried their heads and necks differently from every living vertebrate, we have to assume that the base of their neck was curved strongly upwards," said Mike Taylor, a palaeontologist at Portsmouth University in the UK, who led the study. "In some sauropods this would have meant a graceful, swan-like S-curve to the neck, and a look quite different from the recreations we are used to seeing today."

In their study, Taylor and his team examined the natural neck posture of a wide range of land vertebrates, such as cats, rabbits, turtles and crocodiles. They found that almost all of them hold their necks in an upright, S-shaped curve, even though analysis of the bones alone would suggest the neck should stick out horizontally. His report appears in the journal Acta Paleontologica Polonica.

"The burden of proof is very much on people who want to argue for a different posture," he said. "They are arguing that sauropods are doing it differently to everything else that's alive today."

Dave Martill, another palaeontologist at Portsmouth, said it was easy for fossil hunters and museum staff to get the posture of dinosaurs wrong. But he added: "In this case it is shocking, because our perception of these animals is ingrained, then someone comes along 50 years later and says it doesn't look like this at all."

The comments triggered an immediate response from the Natural History Museum in London, where dinosaur experts were keen to point out that it is almost impossible to be sure how the beasts carried themselves in their natural environment.

"The criticisms that various museums have their dinosaurs in the wrong positions are just nonsense," said Paul Barrett, one of the museum's dinosaur researchers. "I suspect no museum has a sauropod mounted in a position it couldn't achieve. Their necks may have been vertical from time to time, but they were still able to come down low to drink."

There is more to the debate than academic pride. If sauropods walked with their necks upright, it would change palaeontologists' understanding of their behaviour. Their ability to spot predators and potential mates would be dramatically different. It would also change experts' view of their ecological role as the animals would be able to feed on food that was out of reach of many other dinosaurs.

The idea that sauropods held their necks upright is not new. Until the 1950s, most dinosaur experts considered this to be their natural posture. That view changed when scientists suggested that an upright neck would raise the animals' blood pressure catastrophically.

In a study published only last month, the Australian palaeontologist Roger Seymour calculated that if a saurpod held its head upright, it would use half of its energy pumping blood to its brain, requiring a two-tonne heart that would hardly fit inside its ribcage.

But Taylor said the estimates of blood pressure were based on extrapolations from smaller animals, which he doesn't believe are valid for larger creatures.

"It might be that the sauropods found a similar way around the problem as giraffes, but we have no way of knowing. We just can't tell with the sauropods, because they're all dead," said Barrett.

Source: Guardian science