Fossilized Feathers

Not long ago, extinct dinosaurs were considered by most as scaly and dull. All the known fossils of primitive birds (stem avians) could easily fit on a desk and our only look at Mesozoic [250 to 65 million years ago (Ma)] feathers (except for a few isolated plumes) was Archaeopteryx, a theropod dinosaur considered by most to be the most primitive bird.


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Selection for positive illusions

Everybody knows that overconfidence can be foolhardy. But a study reveals that having an overly positive self-image might  confer an evolutionary advantage if the rewards outweigh the risks


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