1) Which of the following is the strongest piece of evidence for why some scientists believe that we are at the start of a sixth mass extinction?

A) decrease in biodiversity

2) Biological species consist of groups of ________.

A) populations

3) Under the biological species concept, what criterion is used to assign populations of organisms to the same biological species?

B) being able to interbreed and produce fertile offspring

4) When brought together in a zoo, two species are capable of mating and producing fertile offspring. Why may they still be considered two distinct species?

C) Zoos are not natural environments.

5) The biological species concept cannot be applied to ________.

B) bacteria that reproduce only asexually

6) The biological species concept cannot be applied to fossils. Which alternate approach to identifying species would be most useful for classifying fossil organisms?

C) an approach based on measurable physical traits

7) A reproductive barrier that prevents individuals from closely related species from interbreeding is an example of ________.

A) a prezygotic barrier

8) What type of reproductive isolating mechanism is described by a situation in which female fireflies mate only with males who emit light in a particular pattern?

D) behavioral isolation

9) The type of reproductive barrier that occurs when two species mate but produce sterile hybrids is referred to as ________.

C) a postzygotic barrier

10) When two frog species, Rana pipiens and Rana sylvatica, mate, the offspring die early in embryonic development. This is an example of ________.

C) reduced hybrid viability

11) Speciation requires ________.

D) genetic isolation

12) Which of the following describes allopatric speciation?

A) A population of squirrels is separated by the Grand Canyon. The two subpopulations evolve into two distinct species.

13) Sympatric speciation specifically EXCLUDES ________.

C) geographic isolation

14) Some fish have bony fins. If the body of water they are in dries out, these fins can be used to help the fish "walk" to another body of water. In this context, bony fins are an example of ________.

A) an exaptation

15) Feathers in birds appear to have first evolved for insulation but later conveyed a new advantage in helping create light aerodynamic surfaces. This switch in function is an example of a(n) ________.

D) exaptation

16) Which of the following would be an example of paedomorphosis?

D) insects that can reproduce in larval stages without reaching mature development stages

17) The current geological era is the ________.

B) Cenozoic

18) Uranium-235, with a half-life of 713,000,000 years, decays to lead-207. If a rock sample is determined to have one-quarter of the uranium-235 content it had when it formed, the age of the rock sample can be estimated to be approximately ________ years old.

D) 1.4 billion

19) Plate tectonics has been responsible for instances of all of the following EXCEPT ________.

B) sympatric speciation

20) The Permian mass extinction is associated with ________.

C) the formation of Pangaea

21) Characid fishes are found naturally only in South America and Africa. Fossils of these fish are not found on any other continents. What is the most likely explanation of this distribution pattern?

B) Characid fishes arose prior to the separation of the African and South American continents.

22) Dinosaurs (aside from the lineage that produced birds) were extinct by the end of the ________.

A) Cretaceous

23) A period of mass extinction is often followed by ________.

A) explosive diversification

24) ________ is the discipline of biology that focuses on classifying organisms and determining their evolutionary relationships.

C) Systematics

25) The science of naming, identifying, and classifying organisms is called ________.

D) taxonomy

26) Which of the following taxonomic levels is most inclusive?

D) class

27) Of the following taxonomic levels, species found within the same ________ are the most closely related.

A) family

28) The wing of a bald eagle is ________ the wing of a penguin.

B) homologous to

29) The wing of a penguin is ________ the wing of a butterfly.

D) analogous to

30) Homology is evidence of ________.

C) common ancestry

31) Analogous structures are evidence of ________.

D) convergent evolution

32) Molecular systematics might examine all of the following types of data EXCEPT ________.

D) anatomical features

33) An ancestral species and all its evolutionary descendants define a(n) ________.

B) clade

34) Which one of the following is the only domain that contains eukaryotes?

D) Eukarya

35) When you go outside, it is common to hear a variety of bird songs. These songs vary among bird species as well as bird flocks. Interestingly, some bird species that are highly unrelated have very similar song qualities. What can you conclude from this phenomenon?

C) The bird songs are analogous traits.

36) What hypothesis did Luis and Walter Alvarez test in relation to the mass extinction of dinosaurs 65 million years ago (MYA)?

C) The mass extinction 65 MYA was caused by an impact of an extraterrestrial object.

37) Why is it INCORRECT to assume that mass extinctions carry only negative impact on the evolution of life on Earth?

A) Mass extinctions are sometimes followed by periods of evolutionary change when other organism groups can flourish and expand in diversity and size.

38) Applying the biological species concept, the sterility of ligers reveals that ________.

C) tigers and lions are separate species

39) ) The natural differences in the ranges of wild tigers and lions is an example of ________.

A) a prezygotic barrier

40. The production of sterile male ligers is an example of ________.

C) a postzygotic barrier

41) Based on the independent and dependent variables represented in the figure and the information you have about common geographic habitats as well as anatomical and gametic compatibility of the four frog species, you initially conclude that reproductive barriers may be due to ________.

C) temporal isolation

42) What can you conclude about the breeding characteristics of these four frog species?

A) The maximum mating activity of the four frog species at different times reduces and/or removes interbreeding.

43). The two squirrel populations are separated by a geographic barrier. If after a long period of time the two species are no longer separated, what evidence is needed to determine if speciation has occurred?

B) The two populations are not interbreeding freely.