Birds formed from Dinosaurs
From bird fossils, we can see how they have evolved over the years, however it is very difficult due to their bone structure. Thier bones are very light and hollow as it is better for flights and their feathers are delicate or course. However, some fossilisation found in limestone may suggest that birds actually can be traced from dinosaurs. Some fine fossils have shown that they once had teeth and a bone structure similar to that of a reptile.
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