Question 1

What are the closest ancestors of humans (genus Homo)?

Accepted Answer

Australopithecines are the closest ancestors of humans (genus Homo) based on evolutionary evidence and fossil records. While chimpanzees are our closest living relatives, they diverged from our common ancestor around 6 million years ago, whereas the first Homo species appeared around 2.4 million years ago, making australopithecines a more direct ancestor. Prosimians and gibbons are much more distantly related to humans.

Question 2

Sharks have cartilaginous skeletons because bone-forming ability had not yet evolved in vertebrates when they originated.

Accepted Answer

Sharks have cartilaginous skeletons because they are part of a group of fish known as Chondrichthyes, which evolved to have cartilage instead of bone. Bone-forming ability was already present in the ancestors of vertebrates before sharks and other cartilaginous fish diverged from the lineage that led to bony fish and ultimately to terrestrial vertebrates.

Question 3

The human lineage began to diverge from those of other primates about

Accepted Answer

The most recent studies suggest that the human lineage began to diverge from those of other primates about 6 million years ago.

Question 4

In lampreys,the notochord is surrounded by a cartilaginous rod.

Accepted Answer

Lampreys, like other members of the subphylum Vertebrata, have a notochord, which is a flexible, rod-shaped structure that supports the body. In lampreys, the notochord is surrounded by a cartilaginous (made of cartilage) rod, which provides additional support and protection.

Question 5

Metamorphosis is

Accepted Answer

Metamorphosis refers to the changing of one body form to another within a species, as seen in the transformation of an aquatic tadpole to a terrestrial frog. Option B refers to genetic variation, option C to a specific type of morphological change, and option D to an evolutionary transition between different animal groups.

Question 6

Which fish were thought to be extinct,but were actually found in living populations?

Accepted Answer

The Coelacanth was thought to be extinct for 66 million years until a living population was discovered off the coast of South Africa in 1938.

Question 7

Which is an incorrect match of taxonomic category and common name?

Accepted Answer

Sarcopterygii refers to lobe-finned fish, not sharks and rays which fall under the category Chondrichthyes.

Question 8

The fins of lobe-finned fish are supported by extensions of the skeleton and are moved by muscles within the fin whereas the fins of ray-finned fish are supported by flexible,nonskeletal elements and are moved by muscles from within the fish's body.

Accepted Answer

This statement accurately describes the difference between the fins of lobe-finned fish and ray-finned fish.

Question 9

Marsupials are distinguished by

Accepted Answer

Marsupials are distinguished by having a marsupium, which is a pouch where they carry and nurse their young.

Question 10

Evolutionarily,the jaws of vertebrates developed from

Accepted Answer

According to current understanding, the jaws of vertebrates (including humans) evolved from the skeletal supports of the third and fourth gill arches of jawless fishes. These skeletal supports became modified and incorporated into the head, eventually developing into the movable, muscular jaws that we see in modern jawed vertebrates. This evolutionary innovation provided many advantages, including the ability to grasp and manipulate prey, leading to the diversification and success of jawed vertebrates. The circular mouth of lampreys and the operculum and claspers are not directly related to the evolution of jaws.

Question 11

A distinguishing feature of the Squamata is their

Accepted Answer

The distinguishing feature of the Squamata is their kinetic skull which allows for a greater range of jaw movement, enabling them to consume prey larger than themselves. The other options, hard shell, external fertilization, and shell-less eggs, are not unique to this group of reptiles.

Question 12

Birds are different from all other living vertebrates because they

Accepted Answer

Birds are uniquely characterized by the presence of feathers, a feature that distinguishes them from all other living vertebrates. While some birds can fly (A), not all do, and other vertebrates like bats also have the ability to fly. The lack of teeth (B) is not unique to birds as some other vertebrates also lack teeth. Being bipedal (D) is not exclusive to birds, as many other animals, including humans, are bipedal.

Question 13

Hagfish are classified as vertebrates,but they do not have a vertebral column.

Accepted Answer

While hagfish are considered vertebrates, they do not have a true vertebral column like other vertebrates. Instead, they have a notochord, which is a flexible rod that runs the length of their body and provides support.

Question 14

The swim bladder is an organ in primitive fish from which the lungs of terrestrial vertebrates developed.

Accepted Answer

The answer of The swim bladder is an organ in...

Question 15

What is a defining characteristic of members of the Class Testudines?

Accepted Answer

The defining characteristic of members of the Class Testudines is that they have a hard shell. This shell is composed of two main parts: the upper carapace and the lower plastron.

Question 16

Reptiles are better adapted to life on land than are amphibians.Which external characteristic would a reptile have to lose to make it roughly externally equivalent to an amphibian in terms of ability to tolerate dry land?

Accepted Answer

Reptiles have scales that help prevent water loss, making them better adapted to dry environments compared to amphibians, which generally have permeable skin that requires moisture.

Question 17

The nearest living relatives of crocodiles and alligators are

Accepted Answer

Recent research has suggested that birds are the closest living relatives to crocodiles and alligators. Both crocodilians and birds are members of the archosaur group, which also includes extinct lineages such as dinosaurs and pterosaurs. This means that crocodiles and alligators are more closely related to birds than they are to other reptiles such as snakes, turtles, or lizards.

Question 18

You need to explain to your study group why the breathing ability of amniotes is different than that of amphibians.Your classmates argue that something like a terrestrial salamander is identical in its breathing mechanism to an amniote.To convince them of the critical breathing innovations of amniotes,you report that in order to breathe as an amniote does,the terrestrial salamander would have to

Accepted Answer

The critical breathing innovation of amniotes is the development of new muscular associations in the ribcage, allowing for more efficient lung ventilation. This is not present in amphibians, including terrestrial salamanders. Growing scales, lungs, or reducing the size of the mouth would not result in the same breathing ability as amniotes.

Question 19

Eutherian mammals are uniquely defined by

Accepted Answer

The answer of Eutherian mammals are uniquely defined by
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Question 20

As a naturalist,you are responsible for training volunteers in the identification of the types of amphibians.The volunteers will use this information to correctly describe the animals to school groups that will visit your nature center.The training documentation for the volunteers lists important characteristics of the different groups of amphibians,but you notice that one of the items on the list is incorrect.Indicate which description is not correct.

Accepted Answer

The answer of As a naturalist,you are responsible for training...

Quiz 26: Animal Diversity: Vertebrates

What are the closest ancestors of humans (genus Homo) ?