BIOL 471 Name:____________________________________

Lawrey

MIDTERM EXAMINATION (100 points)

(28) Indicate whether each of the following statements is true (T) or false (F):

1.T F Polyploidy is more common in plants than in animals.

2. T F A trait can be considered an adaptation if it persists for a long time in a population.

3. T F Spatial separation of populations is necessary for cladogenetic speciation to take place.

4. T F Introgression is a process by which spatially separated populations become genetically differentiated over time.

5. T F All methods of classification are evolutionary and use the biological species concept.

6. T F Fitness is a measure of the reproductive success of individuals.

7. T F Parapatric speciation is evident when reproductive isolation develops between populations that remain contiguous.

8. T F Inclusive fitness of an individual is zero if that individual dies before producing offspring.

9. T F Linnaeus believed that species were immutable.

10. T F Sibling species are good biological species.

11. T F Disruptive selection maintains higher levels of heterozygosity than stabilizing selection.

12. T F If populations become geographically separated, they must be considered separate species.

13. T F Uniformitarianism is a concept that was discussed at length in a book by Lyell.

14. T F One of the explanations for the evolution of altruistic behavior in animals is the concept of kin selection.

 (24) Multiple choice. Circle only one of the choices available: 15. Which characteristic is most likely to be derived (apomorphic) for a group of organisms:
  1. One that is the same for the group as it is for an outside or "out" group
  2. One that is observed commonly in embryological forms of the group
  3. One that is rare in the group
  4. One that is common in the group

    5.  

     

    16. Of the following historical events, which occurred first:

  5. Publication of The Origin of Species by Darwin
  6. Malthus’s essay on population published
  7. Mendel’s first work on genetics published
  8. Publication of The Mutation Theory by De Vries

    9.  

     

    17. Of the following, which is considered by cladists to be the most informative in reconstructing the phylogenetic history of a group of organisms:

  9. Synapomorphies
  10. Symplesiomorphies
  11. Homoplasious characters
  12. Parsimonious characters

    13.  

     

    18. Phenetic analysis differs from cladistic analysis most because:

  13. Phenetic analysis is objective
  14. Phenetic analysis is evolutionary
  15. Phenetic analysis is not evolutionary
  16. Phenetic analysis weighs some characters more than others

    17.  

     

    19. Group selection differs most from kin selection because:

  17. Only group selection can explain the evolution of altruistic traits
  18. Only group selection requires the concept of inclusive fitness
  19. Only group selection goes on in groups
  20. Only group selection goes on in groups of unrelated individuals

    21.  

     

    20. Guy Bush’s model for sympatric speciation predicts that greater species diversity will be found in which of the following kinds of organisms:

  21. Animals
  22. Plants
  23. Host-specific parasites and insects
  24. Bacteria


21. (20) Discuss as completely as possible an example that could be used to illustrate each of the following concepts:

a. Superspecies (syngameon)  hybridizing birches in Europe
 

b. Intrasexual selection  male-male combat to defend mating territories in sea lions
 

c. Frequency-dependent selection  selection favoring rare phenotypes due to lower predation
 

d. Directional selection  selection favoring dark phenotypes of Biston betula in polluted environments
 
 

22.(8) Briefly distinguish between prezygotic and postzygotic isolating mechanisms in speciation, and give an example of each.

prezygotic mechanisms cause divergence prior to fertilization; intersexual rituals (dances, etc.) in fruitflies or use of a different host plant in herbivorous insects.

postzygotic mechanisms cause divergence after fertilization; hybrid offspring are sterile or infertile.
 

23.(12) Briefly distinguish between the following pairs of alternatives, making clear how the difference is evolutionarily significant:

a. homologous vs analogous homologous traits are derived from common ancestral traits, while analogous traits are similar in function but not necessarily derived from a common ancestral trait.

b. monophyly vs paraphyly  a monophyletic group is derived from a common ancestor and includes all the descendants; a paraphyletic group does not include all the descendant groups

c. grades vs clades  a grade level group shows marked divergence from an ancestor but is not necessarily monophyletic, while a clade is monophyletic

d. adaptation vs preadaptation  an adaptation is a trait that confers fitness on individuals that possess it; the term "preadaptation" is used for a trait that does not necessarily confer fitness on individuals when it first appears in a population, but becomes adaptive at some later time
 

24.(8) Briefly define the following terms:

a. Sister groups  in cladistics these are groups that diverge from a common ancestor at the same time
 

b. Typological species  Linnean species recognized by a difference in morphology usually
 

c. Parallel evolution  Evolution of a trait independently in two or more separate lineages
 

d. Founder effect  A rapid genetic differentiation of small vicariant (usually peripheral) populations derived from a larger, more diverse, population caused by genetic drift and other evolutionary pressures