Sat August 18, 2012 9:57am
ANCIENT dolphin-like dinosaurs suffered a very human condition - the bends - as a result of their deep dives, Melbourne researchers have found.
Spending too long at depth causes nitrogen to dissolve in the body - resulting in excruciating pain and internal damage known as decompression syndrome.
Now, it seems human divers are not its only victims.
The Deep-diving dinosaurs study by associate professor John Hayman, published in the journal Naturwissenschaften: Science of Nature, found deformities in 245 million-year-old fossilized remains consistent with the condition.
"Ichthyosarians would not develop decompression sickness from sudden rapid ascent but might well do so if herded into and confined for some time in shallow water by predators," wrote Hayman, of the University of Melbourne.
This was probably because the dinosaur had evolved the ability to dive deep, and remain at depth, for long periods.
"Air inhaled at atmospheric pressure on the surface would be pressurised due to compression of the rib cage at depth, resulting in increased nitrogen absorption," he said.
"When resting at the surface after deep diving ... pressure would again be near atmospheric and the excess nitrogen would come out of solution with possible intravenous bubble formation."
The condition would not have killed the Ichthyosaur immediately, and would not have affected its ability to hunt or reproduce. Instead, the side-effects would have most likely developed later in the animal's life.
Similar conditions have been observed in deep diving sperm whales, he said.