Dinosaurs had bird breathing bones, according to reports in Manchester University News and BBC News, 7 Nov 2007, and ABC News in Science 8 Nov 2007. Jonathan Codd of the Faculty of Life Sciences, and Phil Manning of the School of Atmospheric and Environmental Sciences, Manchester University have studied fossils of therapod dinosaurs and compared their ribs with those of extinct and living birds. They found that the dinosaur ribs had uncinate processes – bony projections from the ribs that help move the sternum (breastbone) during breathing.
Jonathan Codd explained: “Our work on modern birds has shown that the way these animals breathe is more complex than originally thought. The uncinate processes are small bones that act as levers to move the ribs and sternum during breathing. Interestingly, these structures are different lengths in different birds – shortest in running birds, intermediate in flying birds and longest in diving birds. The dinosaurs we studied from the fossil record had long uncinate processes similar in structure to those of diving birds. This suggests both dinosaurs and diving birds need longer lever arms to help them breathe. Finding these structures in modern birds and their extinct dinosaur ancestors suggests that these running dinosaurs had an efficient respiratory system and supports the theory that they were highly active animals that could run relatively quickly when pursuing their prey.”
The scientists believe that their findings are more evidence that dinosaurs evolved into birds. Codd commented: “A number of studies have shown that dinosaurs were the direct ancestors of birds and have identified a suite of avian characteristics in therapods.”
Editorial Comment: It’s humbling for a palaeontologist to have to concede that until someone finds a live dinosaur we actually won’t know how they breathed. Likewise if we can conclude they had an efficient breathing system like birds which enabled them to live active lives, it’s again humbling to admit that all we would have proved is that they were well designed to live active lives. Unless you already embrace evolution as fact, the data on dinosaur breathing does not actually prove they changed into birds. Finding a similar structure in two different living things does not prove that one changed into the other. It simply shows that both creatures used a similar mechanism to function. (Ref. respiration, aves, biomechanics)
Evidence News 12 December 2007