Question

For many years, scientists agreed that dinosaurs existed before birds. Although many dinosaurs were large and heavy, some were very small. The small creatures ran quickly on two long back legs and grasped food with short forelegs. Scientists hypothesized that over a span of 60 million years, these dinosaurs evolved into birds. Their short forelegs became wings. Their scales became feathers. In August 1986 two newly discovered incomplete fossil skeletons caused scientists to change their hypothesis. The newly found fossils have characteristics of modern birds that Archaeopteryx lacked, but they are 75 million years older than Archaeopteryx. A large brain case, wide eye sockets, and a breastbone anchoring the muscles used in flight are hallmarks of a modern bird. The fossils found in 1986 show these characteristics; Archaeopteryx does not. If the identification of the new fossils is correct, it appears now that birds evolved much earlier than scientists had believed.

Which of the following statements BEST summarizes the information above?
A) New fossil data suggest that birds did not develop from dinosaurs but were present at the same time as the earliest dinosaurs.
B) Modern birds are very different from their earliest ancestors and are still developing new traits.
C) Fossils are the only way scientists can study creatures that lived on earth more than 60 million years ago.
D) Birds and dinosaurs evolved from reptiles more than 150 million years ago.
E) Newly found fossils prove that birds developed from larger species of dinosaurs than scientists had originally thought.

Answer 1

New fossil discoveries shed light on the timeline and evolutionary process of birds, suggesting they may have evolved earlier than previously thought, challenging earlier hypotheses.

Step-by-step explanation:

The information provided suggests that the discovery of new fossils with characteristics of modern birds, but predating the previously known Archaeopteryx, is leading scientists to revise their hypotheses about the evolution of birds. These findings indicate that birds may have evolved much earlier than previously thought, and that the evolutionary process from dinosaurs to birds could have taken a different path than initially hypothesized. The best summary of this information would be option A: "New fossil data suggest that birds did not develop from dinosaurs but were present at the same time as the earliest dinosaurs." This choice fits best because it encapsulates the essence of the new discovery, which challenges the original timeline of when birds came into existence.