A winsome dino called Bambiraptor has helped scientists determine that birds inherited a good sense of smell from dinosaurs -- and then improved the faculty.
Birds are long thought to have evolved from small two-footed dinosaurs that over a long period grew feathers, took to dwelling in trees and eventually started to fly. The first identifiable bird was Archaeopteryx, which lived around 150 million years ago.
A common assumption is that these early avians had a poor sense of smell, as evolutionary pressure would have shaped brain resources in favour of vision, balance and coordination rather than olfaction.
Not so, suggests new research published on Wednesday in a journal of Britain's Royal Society.
Researchers in Canada used computed tomography -- the famous CT scan used in medical diagnosis -- to get a 3D image of the skulls of dinosaurs, extinct birds and modern birds.
They measured the likely size of the olfactory bulb, a part of the brain that is used in smell. Among modern-day birds and mammals, a larger olfactory bulb means that the sense of smell is better.
The 157 samples traced the olfactory lineage of modern birds to a group of small carnivores called theropods whose larger family also included the Tyrannosaurus rex.
Early birds, says the study,
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