From time to time history and myth come peculiarly close to one another, casting a new light on old, and often largely dismissed tales. In various Eastern cultures the notion of the winged serpent and the dragon have come down from the ages, only to be cast aside by modern society as fantastic, mythological creations of someone's overactive ancient imagination. Now, it seems, this supernatural beast might have some historical antecedents.
Archaeopteryx lithographica lived during the latter part of the Jurassic period, approximately 150 million years ago, just south of what today is central Germany. This ancient creature combined a reptilian body and tail with bird—like wings and feathers. This strange amalgamation of traits seems like something out of ancient mysticism of the Far East.
This beast has provided a wealth of information about the evolution of flight in birds. However, fossil and skeletal studies indicate that it was not capable of flight. None of the Archaeopteryx fossils discovered to date, including the most mature specimens, exhibit an ossified or bony sternum, the wide bone that extends from the chest to the pelvic area in most modern birds. The main purposes of this structure are to protect internal organs during flight and to act as a sturdy anchoring point for the enormous pectoral muscles necessary for flight. There is no indication that Archaeopteryx ever developed strong pectoral muscles, and perhaps this is one reason why it never developed a sternum. Instead, it retained reptilian gastral ribs, thin braces in the abdominal region, which were not attached to the skeleton and which served only to support and protect internal organs. Researchers believe that flight would have been highly unlikely in an animal with such skeletal characteristics.
Furthermore, the bones in the manus of Archaeopteryx do not seem to have been fused. In modern birds, these bones are fused in order to support the wing. In addition, the ulna of modern birds is marked with small knobs where feathers are anchored firmly to the bone by ligaments. The ulna in Archaeopteryx, however, is smooth, indicating that its feathers were not firmly anchored into the skeleton.
Finally, the skeletal characteristics of Archaeopteryx seem to indicate that this animal was most adapted to terrestrial movement. Its hind legs and pelvis closely resemble those of bipedal theropods and dinosaurs, suggesting that, like these other bipeds, it was adept at running along the ground. In contrast to the posture of modern birds, whose bodies are suspended at the pelvis like a seesaw with the thighbones horizontal, it stood up on its hind legs with its long reptilian tail serving to balance it as well as enhance its ability to coordinate abrupt changes of direction while running. In modern birds all that remains of the tail is a shrunken, fused structure called a pygostyle. Although the foot of Archaeopteryx was bird—like, with fused metatarsals, it was also adapted to running. By way of its peculiar mix of features, it seems to represent a kind of transitionary phase, illustrating an evolutionary leap from reptile to bird and providing insight into the development of flight.
Question:
Suppose that scientists have recently found the skeleton of a bird capable of flight embedded in pre—Jurassic period rock. What effect would this discovery most likely have on their thinking about Archaeopteryx lithographica?
[A] It would support the view that Archaeopteryx lithographica represented a transitionary species between reptiles and birds.[B] It would undermine the view that Archaeopteryx lithographica represented a transitionary species between reptiles and birds.
[C] It would neither support nor undermine the view that Archaeopteryx lithographica represented a transitionary species between reptiles and birds.
[D] It would support the view that Archaeopteryx lithographica failed to develop the pectoral muscles necessary for flight.
Login with GoogleQuestion:
Based on information in the passage, which of the following statements is NOT true?
[A] Archaeopteryx lithographica's skeleton is similar to the skeleton of a modern bird.[B] Archaeopteryx lithographica's tail played a larger role in its daily life than the tail of a modern bird plays in its daily life.
[C] Scientists have studied Archaeopteryx lithographica in order to learn about the development of flight.
[D] Archaeopteryx lithographica shared some characteristics in common with dinosaurs.
Question:
In context, the phrase wealth of information (third paragraph) refers to:
[A] knowledge of recent research projects on the evolution of flight.[B] knowledge about Archaeopteryx lithographica's skeletal structure.
[C] knowledge acquired by scientists studying the development of birds.
[D] knowledge of fossil discoveries in what is now central Germany.
Question:
The author suggests within the confines of the passage which of the following about Archaeopteryx lithographica?
[A] It did not have as well—developed a tail as a modern bird.[B] Its wings had a different function than the wings of a modern bird.
[C] It was less intelligent than a modern bird.
[D] Its skeletal structure made it much larger than a modern bird.
Question:
Suppose scientists were to find a skeleton of Archaeopteryx lithographica that has a sternum similar to the sternum of a modern bird. According to the passage, which of the following beliefs would this finding most strongly challenge?
[A] The belief that Archaeopteryx lithographica lived in what is today Europe[B] The belief that Archaeopteryx lithographica lived in the Jurassic period
[C] The belief that Archaeopteryx lithographica lacked bird—like feathers
[D] The belief that Archaeopteryx lithographica lacked the ability to fly
Question:
Researchers believe that Archaeopteryx differs from modern birds for all of the following reasons EXCEPT:
[A] a lack of feathers.[B] pectoral muscle development.
[C] ossification of the sternum.
[D] knobs found on the ulna.