Which of the following is a characteristic of all chordates at some point during their life cycle? |
B |
Why do adult urochordates (tunicates) lack notochords, even though larval urochordates have them? Larvae use notochords to _____. |
A |
If a tunicate's pharyngeal gill slits were suddenly blocked, the animal would have trouble _____. |
D |
Chordate pharyngeal slits appear to have functioned first as _____. |
B |
Which of the following statements would be LEAST acceptable to most zoologists? |
C |
Which extant chordates are postulated to be most like the earliest chordates in appearance? |
A |
Vertebrates and tunicates share _____. |
D |
All chordates studied to date, except tunicates, share a set of _____. |
A |
Which of the following characteristics is shared by a hagfish and a lamprey? |
D |
A new species of aquatic chordate is discovered that closely resembles an ancient form. It has the following characteristics: external armor of bony plates, no paired lateral fins, and a suspension-feeding mode of nutrition. In addition to these, it will probably have which of the following characteristics? |
B |
The earliest known mineralized structures in vertebrates are associated with _____. |
A |
A team of researchers has developed a poison that has proven effective against lamprey larvae in freshwater cultures. The poison is ingested and causes paralysis by detaching segmental muscles from the skeletal elements. The team wants to test the poison's effectiveness in streams feeding Lake Michigan, but one critic worries about potential effects on lancelets, which are similar to lampreys in many ways. Why is this concern misplaced? |
C |
To reproduce, many plants produce seeds-structures containing embryonic offspring along with nutrients inside a tough case. These offspring develop after being released by the parent plant. To which animal reproductive strategy is seed production most comparable? |
A |
Why do skates and rays have flattened bodies, while sharks are torpedo shaped? |
D |
Which of these statements accurately describes a similarity between sharks and ray-finned fishes? |
C |
The presence of a swim bladder allows the typical ray-finned fish to stop swimming and still _____. |
D |
Which shark structure is closest in function to a swim bladder full of gas? |
C |
If a ray-finned fish is to both hover (remain stationary) in the water column and ventilate its gills effectively, then what other structure besides its swim bladder will it use? |
D |
How did the evolution of the jaw contribute to diversification of early vertebrate lineages? |
C |
It is believed that the coelacanths and lungfish represent a crucial link between other fishes and tetrapods. What is the major feature in these fish in support of this hypothesis? |
B |
Jaws first occurred in which extant group of fishes? |
B |
Which of these might have been observed in the common ancestor of chondrichthyans and osteichthyans? |
A |
Arrange these groups in order from most inclusive (most general) to least inclusive (most specific). |
C |
Suppose, while out camping in a forest, you found a chordate with a long, slender, limbless body slithering across the ground near your tent. This critter could be _____. |
C |
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-meter-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). The class decided to humanely euthanize the organism and subsequently dissect it. Having decided that it was probably not a reptile, two of their original hypotheses regarding its identity remained. Which of the following, if observed, should help them arrive at a conclusive answer? |
B |
The organism was found to have two lungs, but the left lung was much smaller than the right lung. Kelly added that the herpetology instructor had said that in most snakes, the same condition exists. If the size difference between the lungs in this organism is not a shared ancestral characteristic with its occurrence in snakes, then its existence in this organism is explained as which of the following? |
B |
Which of the following could be considered the most recent common ancestor of living tetrapods? |
A |
A trend first observed in the evolution of the earliest tetrapods was _____. |
B |
Fossils of the earliest tetrapods should _____. |
C |
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 _____. |
A |
What is believed to be the most significant result of the evolution of the amniotic egg? |
A |
Which structure of the amniotic egg most closely surrounds the embryo? |
D |
The evolution of similar insulating skin coverings such as fur, hair, and feathers in mammals and birds is a result of _____. |
B |
Which of the following characteristics evolved independently in mammals and birds? |
D |
Suppose you traveled back in time and located the first animals to have evolved feathers. You found that these animals were tree-dwelling ectotherms, able to run quickly but unable to fly. You also noticed that only males had feathers. Which hypothesis of feather evolution would these data most support? Feathers initially evolved in a role associated with _____. |
C |
Mammals and birds eat more often than reptiles. Which of the following traits shared by mammals and birds best explains this habit? |
A |
Which characteristic is common to all the modern representatives of all major reptilian lineages (turtles, lepidosaurs, crocodilians, and birds)? |
D |
Which of these are amniotes? |
C |
Due to its system of air sacs connected to the lungs, the respiratory system of birds is arguably the most effective respiratory system of all air-breathers. Upon inhalation, air first flows into posterior air sacs, then into the lungs, and then into anterior air sacs on the way to being exhaled. Thus, there is one-way flow of air through the lungs, along thousands of tubules called parabronchi. |
C |
The one-way flow of air along parabronchi makes what type of gas exchange mechanism possible, at least theoretically? |
A |
Which of these characteristics added most to vertebrate success in relatively dry environments? |
A |
Which of the following are the only extant animals that descended directly from dinosaurs? |
C |
During chordate evolution, what is the sequence (from earliest to most recent) in which the following structures arose? |
A |
Which clade does NOT include humans? |
B |
Primate evolution and behavior, such as hunting skills, have been directed in part by the development of depth perception. What anatomical change made depth perception possible? |
C |
What group of mammals have (a) embryos that spend more time feeding through the placenta than the mother's nipples, (b) young that feed on milk, and (c) a prolonged period of maternal care after leaving the placenta? |
A |
Which of the following represents the strongest evidence that two of the three middle ear bones of mammals are homologous to certain reptilian jawbones? |
D |
Which of the following is the most inclusive (most general) group in which all of the members have fully opposable thumbs? |
C |
Which of these would a paleontologist most likely do to determine if a fossil represents a reptile or a mammal? |
D |
Female birds lay their eggs, thereby facilitating flight by reducing weight. Which "strategy" seems most likely for female bats to use to achieve the same goal? |
A |
Unlike eutherians, both monotremes and marsupials _____. |
B |
On the back of your skull you can feel a small bump, below which is an opening where the spinal cord enters the skull. The location of this opening toward the bottom of the skull is significant in evolutionary biology for what reason? |
C |
Brown et al. and Morwood et al. reported in 2004 that they had found skeletal remains of a previously unknown type of hominin, now dubbed Homo floresiensis, on the Indonesian island of Flores. These hominins were small (approximately 1 meter tall) with small braincases (approximately 380 cubic centimeters) as compared with other hominins. The remains of H. floresiensis were found alongside handmade stone tools and the remains of dwarf elephants that also inhabited the island, suggesting that H. floresiensis was able both to make tools and to coordinate the hunting of animals much larger than itself. H. floresiensis is estimated to have lived at the site where the remains were found from at least 38,000 years ago to 18,000 years ago. |
C |
In what respect do hominins differ from all other anthropoids? |
C |
The table above is a comparison of several characteristics of H. floresiensis to those of nine other hominin species (arranged roughly from oldest to most recent). What do these data suggest? |
A |
Refer to the paragraph on Brown et al. and Morwood et al. It is speculated that H. floresiensis and H. sapiens may have lived on Flores concurrently. Suppose researchers obtained mitochondrial DNA samples from the H. floresiensis remains, amplified a 1000-base-pair sequence via PCR, and compared it to that of several currently living H. sapiens native to Indonesia, North Africa, and North America. Also suppose H. floresiensis were found to differ from the average Indonesian H. sapiens in 28 base pairs, from the average North African H. sapiens in 51 base pairs, and from the average North American H. sapiens in 53 base pairs, while two randomly selected H. sapiens differed from each other in an average of 21 base pairs. What would you surmise from these data? |
D |
Arrange the following taxonomic terms in order from most inclusive (most general) to least inclusive (most specific). |
B |
Which of these traits is most strongly associated with the adoption of bipedalism? |
D |
Which of the following statements about human evolution is correct? |
D |
With which of the following statements would a biologist be most inclined to agree? |
A |