Name_____________________________ Class ______________________ Date ______

Reading Guide

Section 18–1 Finding Order in Diversity (pages 510–515)

Assigning Scientific Names


1. Complete the graphic organizer.
















2. Why is it confusing to refer to organisms by common names?



3. What is binomial nomenclature?



4. What genus does the grizzly bear, Ursus arctos, belong to?


5. What is the correct way to write scientific names in the binomial nomenclature system?



7. What is the science of naming and grouping organisms called?



The Linnaean Classification System

7. The goal of systematics is to organize living things into groups, called                           , that have biological meaning.


8. The largest taxonomic category in the Linnaean system of classification is the                , while the smallest is the                                                      .


9. Similar classes are grouped into a(n)                              , and similar orders are grouped into a(n) .


10. List the taxonomic categories in order from the largest to the smallest.



Section 18–2 Modern Evolutionary Classification (pages 516–522)

Evolutionary Classification

11.           How did Darwin’s theory of evolution change the way biologists thought about classification categories.



12.           Describe the goal of phylogenetic systematics (evolutionary classification).



13.           Which group of organisms would have the most recent common ancestor: the members of a clade corresponding to a genus or the members of a clade corresponding to an order? Explain your answer.



14.             Use the Venn diagram to compare and contrast the definitions of the Linnaean class Reptilia and the clade Reptilia.


Class Reptilia                          Clade Reptilia


Text Box: Both are classifi-
Text Box: Old classification system
Some are paraphyletic
Does NOT include
Text Box: Newer classification system             
All are
Does include





















15. All species descended from a(n)                                    are part of a monophyletic group.


16.                                            is the study of how living and extinct organisms are related to one another.



17. A clade includes a common ancestor and all its descendants, living or                           .



18. A diagram that shows the evolutionary relationships among a group of organisms is called a(n)   _________.


19. The place where the ancestral lineage splits on a cladogram is called a fork, or a(n)         _______________.


20. Characteristics shared by members of a clade and only by members of that clade are  called                                             ____________.


21. Examine the cladogram below:

·    Shade in the two organisms that belong to a clade that does not include the third organism. Cross-hatch the organism that does not belong to the clade.

·    Circle the node  on the cladogram that shows the most recent common ancestor of the crab and the barnacle.

·    Mark an X on the node on the cladogram that shows the most recent common ancestor of mollusks and crustaceans.

·    Underline the characteristic that all three organisms have in common.


























DNA in Classification

Use the figure below to answer Questions 22–24.























22. According to the figure, which species is most closely related to red pandas?



23. Although giant pandas and raccoons share some distinct anatomical similarities, they are in different clades. What type of evidence do you think was used to construct this diagram?



24. Biologists had previously classified giant pandas together with raccoons and red pandas. What did DNA analysis reveal about giant pandas and bears?



Section 18–3 Building the Tree of Life (pages 523–528)

Changing Ideas About Kingdoms

25. What fundamental traits did Linnaeus use to separate plants from animals?



26. What types of organisms were first placed in the kingdom Protista?



27. What types of organisms were placed into the kingdom Fungi?



29. Why did scientists place bacteria in their own kingdom, the Monera?



29. What two kingdoms was kingdom Monera separated into?








30. Complete the concept map.














31. What is a domain?



The Tree of All Life

32. Complete the chart below.


Classification of Living Things






Salmonella typhimurium



Sulfolobus archaea





mushrooms, yeasts




Sponges, worms, insects, fishes, mammals


Match the kingdom with the description that applies to members of that kingdom.

Kingdom                                            Description

               33.    “Protista”                     A. They feed on dead or decaying organic matter.

               34.    Fungi                           B. They have no cell walls and they move about.

               35.    Plantae                         C. They are a “catchall” group of eukaryotes.

               36.    Animalia                      D. They include mosses and ferns.


37. What characteristics led camels to be classified in the same domain, kingdom, phylum, and class as dogs.