Another Puzzle Piece
Writing in the journal Nature, researchers from Ohio and Harvard universities report that rather than reptilian lungs, dinosaurs sported a much bigger and more complex system of air sacs similar to that found in today's birds.
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The exact function of the skeletal modifications is not understood, but scientists think the gaps in the bones evolved to lighten bone structure, allowing dinosaurs to walk upright and made it easier for birds to fly
Booyah!