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Most scientists think birds evolved from dinosaurs about 150 million years ago. But a sparse fossil record has provided ammunition to those who insist that birds arose independently. A stunning new fossil makes that idea virtually untenable. And a second paper this week brings dinosaur feathers vividly to life, offering new clues to why this instrument of flight first evolved in flightless creatures. On page 571 of this week's issue of Science, paleontologists unveil Haplocheirus sollers, a new genus of alvarezsauroid—a group of dinosaurs once thought to be flightless birds. The nearly complete skeleton, unearthed from 160-million-year-old mudstone deposits in northwestern China's Junggar Basin, extends the fossil record of alvarezsauroids back in time by a whopping 63 million years—making it about 15 million years older than the earliest known bird, Archaeopteryx.