Interestingly, this fossil fills a 70-million-year-long gap in our knowledge between the early bird-like dinosaurs (Archaeopteryx) and modern birds.

Birds descended from the dinosaurs, but researchers have known relatively little about how the bird's brain took shape over millions of years. A new fossil sheds light on that mystery.

The brains of today's birds facilitate a level of cognitive prowess and behavioral complexity rivaled only by mammals. But how the avian brain evolved over many millions of years from an ancestral dinosaurian form has long puzzled scientists.

Researchers hope the "exquisitely preserved" fossil will cast new light on an enduring mystery in paleontology.

An almost perfect intermediate between Archaeopteryxand modern birds has been discovered with its skull preserved in extraordinary three-dimension. To find such an intact fossil bird that dates back to the Mesozoic is almost unheard of,