Question 1

A species of cave beetle that lives in total darkness is blind but has remnants of what looks like eyes. These "eyes" are

Accepted Answer

Remnants of what looks like eyes in a completely dark environment suggest that these structures are vestigial, meaning that they were functional eyes in an ancestor but have since lost their original function due to lack of use.

Question 2

The genus Lycopodium includes plants that evolved before the breakup of Pangaea. The genus Sequoiadendron (Sequoia trees)evolved after Pangaea split into separate landmasses. Which genus would you expect to have the widest distribution of living representatives across the modern continents?

Accepted Answer

Since Lycopodium evolved before the breakup of Pangaea, it would have had more time to establish a widespread distribution before the continents drifted apart. Thus, it is more likely to have representatives across modern continents compared to Sequoiadendron, which evolved after the separation of the continents.

Question 3

Convergent evolution occurs when natural selection causes distantly related organisms to

Accepted Answer

Convergent evolution occurs when distantly related organisms independently evolve similar structures or characteristics in response to similar environmental challenges. This is not the same as evolving into the same species or merging into one population, and while both analogous and homologous characteristics may occur, they are not required for convergent evolution to take place.

Question 4

Which of the following is not homologous to any of the others?

Accepted Answer

The wing of a bat, the flipper of a whale, and the arm of a human are all homologous structures as they were all derived from a common ancestor with a similar bone structure. However, the leg of a grasshopper evolved independently and does not share a common ancestor with the other structures.

Question 5

One of the reasons scientists have had so much difficulty finding a cure for HIV/AIDS is that the HIV virus is quick to evolve resistance to the drugs used to treat it. What is the most likely mechanism for this type of evolution?

Accepted Answer

The HIV virus has a high mutation rate, leading to genetic variations. Some variants may have mutations that confer resistance to drugs, allowing them to survive and reproduce, passing on the resistant genes.

Question 6

Which of the following statements about evolution is true?

Accepted Answer

Evolution can result in both the addition and loss of traits in existing organisms. This can occur through processes such as mutation, natural selection, genetic drift, and gene flow. Over time, these processes can lead to changes in the characteristics of populations and the emergence of new species.

Question 7

The number of different types of organisms found on Earth is a result of

Accepted Answer

The number of different types of organisms found on Earth is a result of speciation, which is the process by which new species arise. This occurs when populations of organisms become isolated from each other and adapt to different environments, eventually leading to the development of distinct species. Continental drift and the theories of Darwin and common descent can influence the process of speciation, but they are not the direct cause of the number of different types of organisms on Earth.

Question 8

A population of mice lives along a river. Some mice cross the river to establish a new population. Eventually, due to genetic changes, these two groups of mice can no longer interbreed. This is an example of

Accepted Answer

The scenario described is a classic example of speciation, where a single population separates into two distinct populations that evolve separately over time until they can no longer interbreed. This is a natural process that occurs due to genetic changes in the populations. Genetic drift is a random process that can lead to changes in the gene pool of a population, but it may not necessarily lead to speciation. Artificial selection is a process where humans select certain traits in a population to breed and does not involve natural genetic changes. Creationism is a religious belief and not a scientific explanation for the origin of species.

Question 9

Both insects and humans evolved jointed legs to allow locomotion on land. These structures are considered analogous because insects and humans

Accepted Answer

The fact that insects and humans evolved from different ancestors makes their jointed legs analogous rather than homologous (which would imply a common ancestor).

Question 10

The following diagram shows the bone structure of a whale flipper and a bat wing. Which of the following suggests that these two structures are homologous rather than analogous?

Accepted Answer

The presence of five fingerlike bone projections in both structures suggests they have a common ancestral origin and are therefore homologous. This is in contrast to analogous structures, which may serve a similar function but have evolved independently and do not share a common ancestor with similar structures in other organisms. The other options (B, C, and D) are not sufficient to suggest homology.

Question 11

The fossil record

Accepted Answer

The fossil record contains numerous examples of transitional species that demonstrate the evolution of major new groups of organisms from previously existing ones. It does not prove that all known species appeared at the same time or that humans date back to the origins of life. Additionally, the fossil record is a natural occurrence and not artificially created by scientists.

Question 12

Convergent evolution produces

Accepted Answer

Convergent evolution produces analogous characteristics. These are traits that have similar functions, but arise from different evolutionary origins. They result from organisms adapting to similar environments or ecological niches, rather than sharing a common ancestry.

Question 13

Flounder (a type of fish)generally match the color of the sandy bottoms they inhabit. Their color allows them to hide from other organisms that might eat them. This is an example of

Accepted Answer

Flounder's ability to match the color of their environment is an adaptation, a characteristic or behavior that allows an organism to survive and reproduce in its environment. Speciation is the process by which new species arise, continental drift refers to the movement of Earth's continents, and guided mutation is not a recognized scientific concept.

Question 14

Speciation can occur when

Accepted Answer

Geographical isolation can result in the accumulation of genetic differences between two populations, eventually leading to the development of new species with unique characteristics. This process is known as allopatric speciation. Gene flow (choice A) can prevent speciation by keeping the gene pools of two populations similar. While mutations (choice B) can contribute to genetic diversity, they alone are not enough to cause speciation. Choice D is incorrect because over time, genetic drift and other factors will cause the gene pools of two populations to diverge, even if the initial gene pools were identical.

Question 15

The hands of a human and the hands of a chimpanzee are similar in structure because humans

Accepted Answer

The hands of humans and chimpanzees are similar in structure because they share a recent common ancestor. Both species belong to the same family of primates and have evolved from a common ancestor that had hand-like appendages. Over time, natural selection has favored variations in hand structure that are adaptive to the specific needs of each species. Therefore, similarities in hand structure between humans and chimpanzees are due to common ancestry and not because one evolved from the other or because of artificial selection.

Question 16

The fact that small, nonfunctioning hind legs are found in the skeletons of many snakes suggests that snakes

Accepted Answer

The presence of small hind legs in snake skeletons suggests that snakes have evolved from organisms that once had legs, likely lizards or an ancestor of lizards that had limbs. This is supported by both genetic and fossil evidence. Therefore, choice B is the best answer. The other options (A, C, and D) are not supported by scientific evidence.

Question 17

The wings of a bird and the wings of a bat both form from the front appendages (arms). The bird wing is covered by feathers and the bat wing consists of a thin layer of skin stretched between the "finger" bones. Are the wings of the bird and bat homologous or analogous?

Accepted Answer

The wings of the bird and the bat are homologous because they both evolved from the front appendages, specifically the arms. However, they are also analogous because they evolved differently and serve different purposes. The feathers of birds are adapted for flight and thermoregulation, while the thin skin of bats is adapted for flight and echolocation. Therefore, both homology and analogy apply to the wings of birds and bats.

Question 18

Two different species may have similar features because of

Accepted Answer

Similar features in different species can often be explained by descent from a common ancestor. This means that the species evolved from a common ancestor and therefore share some traits because of their shared ancestry. Genetic drift can cause differential allele frequencies in populations over time, but it does not necessarily lead to similar features in different species. The fossil record can give us information about the evolution of different species, but it does not necessarily explain similarities between them. Artificial selection is a process where humans selectively breed organisms for certain traits, but this does not apply to naturally occurring similarities between different species.

Question 19

Evolution is

Accepted Answer

Evolution is strongly supported by scientific evidence, including the fossil record, genetic studies, and observations of present-day organisms. This is the prevailing scientific theory and is widely accepted within the scientific community.

Question 20

Pangaea is

Accepted Answer

Pangaea is an ancient, giant continent that existed during the Paleozoic and Mesozoic eras before breaking apart into the continents we see today.

Quiz 17: How Evolution Works