Dinosaurs Had Respiratory System Like Birds
LONDON — Dinosaurs may have been fierce predators but they had a respiratory system similar to modern birds such as the sparrow, scientists said Wednesday.
Ancient beasts such as the mighty Tyrannosaurus rex were thought to have had lungs similar to crocodiles but researchers in the United States have discovered the creatures had more in common with birds than reptiles when it came to breathing.
"The pulmonary system of meat-eating dinosaurs such as T.rex in fact shares many structural similarities with that of modern birds, which from an engineering point of view, may possess the most efficient respiratory system of any living vertebrate inhabiting the land or sky," said Leon Claessens, of Harvard University in Massachusetts.
Claessens and Patrick O’Connor, of Ohio University’s College of Osteopathic Medicine, compared dinosaur bones in museums in the United States, Germany and England with modern birds. They looked at how the skeleton related to the air system in areas such as the neck and chest.
The researchers found that dinosaurs had a respiratory system with the potential to support elevated rates of metabolism. Although it is not identical to birds, O’Connor said it is nothing like the crocodile system.
"What was once formally considered unique to birds was present in some form in the ancestors of birds," he added in a statement.
The study, reported in the science journal Nature, is the latest to show similarities between dinosaurs and birds. Recent research suggests some dinosaurs may have had feathers and incubated their eggs.
Claessens and O’Connor said their research does not mean dinosaurs were habitually warm-blooded. They believe the creatures were somewhere between what scientists describe as warm and cold blooded animals.
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