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First in Flight?

Feathers were flying in the science world after the fossils of a four-winged dinosaur were recently discovered in China. While most scientists agree that birds probably evolved from dinosaurs, they have long argued over how birds learned to fly. Some think that flight began with tree-dwelling creatures that glided from branch to branch. Others say that flying started on the ground after some dinosaurs began flapping their wings to run faster. This new species of dinosaur could help prove who's right.

The dinosaur, named Microraptor gui, is believed to have lived some 130 million years ago. An odd-looking creature, it had a body the size of a pigeon and wings on each of its four limbs. Feathers covered most of the dinosaur, including its feet. Long leg feathers would have made running difficult, but the dinosaur's four wings were perfect for gliding. Scientists believe that the creature lived in trees and glided much like today's flying squirrels. While this new dinosaur supports the idea that gliding came before wing flapping, no one is quite ready to say, “I told you so.” Scientists agree that more research is needed before we'll know which theory of flight is for the birds.


  • evolve: To develop slowly from or into something else.
  • tree-dwelling: Living in trees.

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  1. Why do scientists think that the dinosaur Microraptor gui is related to modern birds?
    [anno: The fossil for Microraptor gui has four wings.]
  2. Why do you think the Microraptor gui became extinct? How might the dinosaur's wings have been a weakness? Write a few sentences explaining your answer.
    [anno: Answers will vary but could include that since the dinosaur could not fly but only glide, the dinosaur might not have been able to escape from being eaten as well as dinosaurs that could eventually fly.]