After the cataclysm that wiped out most of the dinosaurs, only one group of birds remained: the ancestors of the birds we see today. A newly described fossil from one of those extinct bird groups, cousins of today’s birds, deepens the mystery of why only one family of birds survived the extinction.

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After the cataclysm that wiped out most of the dinosaurs, only one group of birds remained: the ancestors of the birds we see today. A newly described fossil from one of those extinct bird groups, cousins of today’s birds, deepens the mystery of why only one family of birds survived the extinction.