After reading the paragraph below, answer the questions that follow.
The first fossil of Archaeopteryx, which lived about 150 million years ago, was found in the Solnhofen Quarry in Germany. Archaeopteryx has an interesting collection of characters that led to the hypothesis that it represented an evolutionary transition between modern-day birds and small bipedal dinosaurs. The fossil reveals the imprint of feathers, which connect Archaeopteryx to birds, although they do not present direct evidence of flight. Unlike birds, however, Archaeopteryx was shown by the fossil record to have had teeth, functional claws on the wings that may have been used for climbing trees or holding prey, and a long, bony tail. Birds have a fused collarbone, which was found in Archaeopteryx as well. However, the structure of the sternum differed between the two. In birds, the sternum is keeled (raised and slightly concave); the keel of the sternum serves as an attachment site for the flight muscles. Archaeopteryx had a flat sternum, similar to that found in reptiles.
If you were constructing a phylogenetic tree for the evolution of birds, which characters found in Archaeopteryx might provide evidence that birds and dinosaurs had a common ancestor?
◦ keeled sternum, claws, long, bony tail
◦ feathers, wings, fused collarbone
◦ teeth, flat sternum, claws
◦ teeth, feathers, keeled sternum
Hormonal Changes in Puberty Girls and boys follow very different hormonal paths at this life stage
Gary Alvis, The Painted Hills, John Day Fossil Beds National Monument, Oregon.
Record the AC frequency as shown on the meter and subtract 50 from the reading (e.g., 60.50 -50.00 = ...
Use the answer sheet below the problems for your answer
Answer
The origin and spread of modern H. sapiens, reconstructed from genetic and fossil evidence.