Exam 34: The Origin and Evolution of Vertebrates

The following questions refer to the description below. Terry catches a ray-finned fish from the ocean and notices that attached to its flank is an equally long, snakelike organism. The attached organism has no external segmentation, no scales, a round mouth surrounded by a sucker, and two small eyes. Terry thinks it might be a marine leech, a hagfish, or a lamprey. -Terry saved some of the tooth-like objects within the hagfish's round mouth to analyze their composition in his mentor's biochemistry research lab. Terry will find that they are composed of the same protein found in tetrapod

The following questions refer to the description below. While on an intersession course in tropical ecology, Kris pulls a large, snakelike organism from a burrow (the class was granted a collecting permit). The 1-m-long organism has smooth skin, which appears to be segmented. It has two tiny eyes that are hard to see because they seem to be covered by skin. Kris brings it back to the lab at the field station, where it is a source of puzzlement to the class. Kris says that it is a giant oligochaete worm; Shaun suggests it is a legless amphibian; Kelly proposes it belongs to a snake species that is purely fossorial (lives in a burrow). -Which one of these, if found, should clear up any remaining doubt as to the identity of the organism?

The following questions refer to the description below. Terry catches a ray-finned fish from the ocean and notices that attached to its flank is an equally long, snakelike organism. The attached organism has no external segmentation, no scales, a round mouth surrounded by a sucker, and two small eyes. Terry thinks it might be a marine leech, a hagfish, or a lamprey. -Having caught and handled a hagfish, what will Terry's shipmates most likely require Terry to do before returning to further fishing?

To which of the following are the scales of chondrichthyans most closely related in a structural sense?

What should be true of fossils of the earliest tetrapods?

Jaws first occurred in which extant group of fishes?

In the United States and Canada, bats use one of two strategies to survive winter: They either migrate south, or they hibernate. Recently, those that hibernate seem to have come under attack by a fungus, Geomyces destructans (Gd), an attack that is occurring from Missouri to southern Canada. Many infected bats have a delicate, white filamentous mat on their muzzles, which is referred to as white-nose syndrome (WNS). The fungus invades the bat tissues, causes discomfort, and awakens the bat from its hibernation. The bat fidgets and wastes calories, using up its stored fat. The bat then behaves abnormally, leaving its cave during daytime in winter to search for food. Their food, primarily insects, is scarce during the winter, and the bats ultimately starve to death. Since 2007, it is estimated that up to 1 million bats have perished from WNS. -Gd is a cold-loving fungus. Thus, which characteristics of normal bat behavior can be most expected to favor the spread of this fungus to uninfected bats?

At 5, 10, and 15 hours in the graph below, which of the following statements should be true?

Which of these statements about human evolution is correct?

What is the single unique characteristic that distinguishes extant birds from other extant vertebrates?

Which of the following represents the strongest evidence that two of the three middle ear bones of mammals are homologous to certain reptilian jawbones?

Which of these species is currently thought to have coexisted (at the same time and places)with H. neanderthalensis?

Which of the following statements about human evolution is correct?

Which of these species had members who moved out of Africa?

The lamprey species whose larvae live in freshwater streams, but whose adults live most of their lives in seawater, are similar in this respect to certain species of

Which of the following is the most inclusive (most general)group, all of whose members have fully opposable thumbs?

Which of the following could be considered the most recent common ancestor of living tetrapods?

Among extant vertebrates, a sheet of muscle called the diaphragm is found in

Which era is known as the "age of reptiles"?

For the following items, match the extant vertebrate groups with the descriptions. -Internal fertilization, leathery amniotic egg, and skin that resists drying are characteristics of