TIPS: Targeted Interventions for Proficiency in Science
Main Site »
RPDP Home
Contact Us
Tips Home
Middle School »
High School »
Life Science

Content Benchmark L.12.D.1
home / life science / diversity of life/

Life Science
Heredity
Structure of Life
Organisms and Their Environment
Diversity of Life
  L.12.D.1
  L.12.D.2
  L.12.D.3
  L.12.D.4
  L.12.D.5
  L.12.D.6
Content Areas
Nature of Science (NOS)
Life Science
Earth Science
Physical Science

Students know organisms can be classified based on evolutionary relationships. E/S

When teaching all of the L.12.D benchmarks, it is imperative to help students understand the process of science. Most objections and misconceptions about evolution are directly related to the misunderstanding of how science works. When students understand the nature of science, they will understand how scientists have studied the process of evolution. As questions arise about a “supernatural” creation of Earth and the Universe, students who understand the nature of science will understand why supernatural forces cannot be studied as part of scientific processes.

Organisms can be classified into groups based on morphological, behavioral, and evolutionary relationships. Classifying organisms is important to scientists as it provides a framework and a common “language” which enables scientists everywhere to study and understand more about life on Earth. Biological classifications are based on how organisms are related. Taxonomy is the science of classification and includes the naming, describing, and classifying organisms into various groups.

The Linnean system of classification is a hierarchical classification system that has been used by scientists for nearly 200 years. This system, originally based on morphological and behavioral characteristics is still in use today, although with many modifications. The highest category in the hierarchy is “all living things” and the lowest category is a single species. A species is generally identified as a group of organisms which are capable of reproducing with the production of fertile offspring. The hierarchical divisions are as follows: Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species. The following table shows the Linnean classification hierarchy of two organisms.

Category Domestic cat Common buttercup
Domain Eukarya Eukarya
Kingdom Animalia (animals) Planate (plants)
Phylum/Division Chordata (chordates) Anthophyta (flowering plants)
Class Mammalia (mammals) Dicotyledons (dicots)
Order Carnivoria (carnivores) Ranunculales
Family Felidae (cats) Ranunculaceae (crowfoot family)
Genus Felis Ranunculus
Species silvestris acris

Scientists currently recognize 3 Domains and 6 Kingdoms of living things:

Three Domains

Bacteria

Archaea

Eukarya

The Six Kingdoms

Bacteria

Archaea

Protista

Plantae

Fungi   

Animalia

To learn more about Linneas and the Linnean system of classification see:  http://huntbot.andrew.cmu.edu/HIBD/Exhibitions/OrderFromChaos/pages/intro.shtml  and http://anthro.palomar.edu/animal/animal_1.htm

Charles Darwin was a scientist/naturalist who gathered a significant amount of evidence indicating that populations change over time as the population amasses adaptations to environmental conditions. During voyages on the HMS Beagle, Darwin carefully observed, characterized and categorized different populations that seemed to have arisen from common ancestors. One of the classic examples is that of the Galapagos finches. Finches on different islands, geographically isolated from each other, had specific variations that seemed to aid in survival on the particular island. The finches were similar to each other and all had similarities to the finches on the mainland of South America, yet all had specific adaptations that enabled survival in their particular area. This type of evolutionary change is called adaptive radiation.


This diagram from http://www.pbs.org/wgbh/evolution/library/01/6/image_pop/l_016_02.html
illustrates the finches that Darwin observed. All of the finches are believed to have arisen from a common ancestor, but evolved different characteristics due to environmental conditions and available food sources on different islands.

These observations, as well as, other data collected on numerous organisms led Darwin to the theory of natural selection as the mechanism for evolution.

To learn more about Darwin’s studies and theory, see:
http://www.geo.cornell.edu/geology/GalapagosWWW/Darwin.html
For a short video about Darwin and his studies, see http://www.pbs.org/wgbh/evolution/library/11/2/e_s_2.html

Linneas, Darwin, and other early scientists classified organisms by comparing physical characteristics. While physical characteristics are still useful in classification, it is now generally agreed by scientists that the evolutionary history can be more useful and accurate in the organization and classification of organisms. Organisms can be grouped according to their shared evolutionary history. Organisms that have a recent common ancestor are more closely related than those that have a more distant common ancestor. Phylogeny is the classification of organisms based upon their evolutionary history. Evidence used to explain and determine phylogeny includes fossils (see L.12.D.3), biochemistry (see L.12.D.2), genetics (see L.12.A.1), and structure. Phylogenetic trees are used to illustrate evolutionary relationships. The following phylogenetic tree illustrates the relationship of several animals. For example, the following diagram indicates that salamanders and frogs are more closely related than mammals and turtles.

To learn more about phylogeny and its usefulness in classification see:
http://www.tolweb.org/tree/learn/concepts/whatisphylogeny.html
and http://evolution.berkeley.edu/evolibrary/article/phylogenetics_01

Homologous structures are anatomical features of different organisms that have a similar appearance or function that are inherited from a common ancestor. The wing of a bird, the forelimb of a cat, and the arm of a human are homologies because they are structurally and functionally similar and they are inherited from a shared ancestor. The more homologies different organisms have, the closer they probably are genetically.

This figure illustrates homologous structures in the forelimbs of several animals.
Source: http://virtuallaboratory.net/Biofundamentals/lectureNotes/Topic1-5_Evo.htm

Analogies are anatomical structures that have similar form or function in different species that have no known common ancestor. For example, the wings of a bat and the wings of a moth are similar in shape and function, but are very different internally and the wings did not evolve from a shared ancestor.

For additional information and examples of homolgies and analogies, see: http://evolution.berkeley.edu/evolibrary/article/0_0_0/similarity_hs_01


Biological evolution is the best scientific explanation for how life on Earth has changed and how it continues to change. We do not understand everything about evolutionary relationships among organisms. The evolutionary history of an organism is determined based on current knowledge, evidence, observations, and testing, and as new data becomes available, our understanding of relationships between organisms will continue to be revised. DNA analysis and other molecular technology available today provide data and information which can be used in classification system. (See L.12.D.2)

back to top


Performance Benchmark L.12.D.1

Students know organisms can be classified based on evolutionary relationships. E/S

Common Misconceptions associated with this benchmark

1. Appearance Misconceptions

Students incorrectly think that if organisms look alike, then they must have a common evolutionary history. When asked to classify organisms, students use obvious physical features, rather than processes or genetic relationships.

Convergent evolution is the development of similar traits or characteristics by taxonomically different groups of organisms. Convergent evolution often occurs when two groups of organisms occupy similar niches. Just because two organisms may have developed a similar characteristic trait, it does not necessarily mean that they are closely related. For examples, birds and bats both have wings, an adaptation that allows them to fly. However, bats and birds evolved independently of each other.

For a discussion of convergent evolution, go to
http://www.pbs.org/wgbh/evolution/library/01/4/l_014_01.html

2. Natural Selection Misconceptions

Students incorrectly believe that adaptations and hence, natural selection occurs as an organism changes due to some need, desired use of function, or an environmental condition, and that this change is then automatically passed to their offspring.

This misconception was held by Lamarck in the 1800’s, who concluded that parents can pass acquired characteristics on to their offspring.

Students have difficulty understanding basic concepts of evolution such as natural selection. They don’t conceptualize that mutations often occur randomly and that some of these random changes are selected for because they help in the survival and reproduction of the organism.
To read more about Lamarck, see: http://www.pbs.org/wgbh/evolution/library/02/3/l_023_01.html

Evolution through natural selection occurs instead through variations and changes in DNA that occur naturally and randomly. If a particular mutation is found in an organism which enables the organism to better survive in its environment, the organism is more likely to live, and to reproduce (survival of the fittest). Because the animal was born with that change and that it is in the DNA of the organism, that DNA, and therefore the trait, can be passed on to the offspring. Over time, when a significant number of changes have occurred, a new species may develop. Mechanisms of evolutionary change include:

mutation—changes in the DNA of an organism
migration—a group of organisms from a particular species may migrate to a new, geographically isolated area and begin interbreeding among themselves but not with the parent population
genetic drift—normal variations that occur in the genes of organisms, related to mutations
natural selection—the organisms most likely to live and reproduce will be the ones that pass on their traits

More information about evolution through natural selection can be found at: http://www.pbs.org/wgbh/evolution/library/11/2/e_s_4.html

3. Scientific Theory Misconceptions

Students incorrectly think that evolution is “just a theory.” Students think that a scientific theory is similar to a theory as used in everyday discussions, that is, a theory is just a guess or a hunch, or what one person thinks.

The common-every-day use of the word theory means a guess or a hunch. A scientific theory does not have the same meaning as this common every-day theory. A scientific theory is well substantiated, supported by facts, laws, and tested hypotheses. A scientific theory is an explanation based on observation, experimentation, and reasoning. It is recognized in the scientific community as a general principal that helps explain natural phenomena. Theories can be tested, modified, and at times, rejected as new information and scientific knowledge is acquired. Scientific theories are valid and provide a basis for exploring new questions.

Additional definitions of scientific theory can be found at,
http://www.ncsu.edu/labwrite/res/res-glossary.html

For NSTA’s position statement on scientific theories see: http://www.nsta.org/positionstatement&psid=10
(scroll down to the section entitled: The Nature of Science and Scientific Theories).

4. Human Evolution Misconceptions

Students incorrectly think that evolution of humans means the humans evolved from monkeys.

A comparison of human to chimpanzee DNA shows about a 98% similarity indicating that there is a genetic and evolutionary link. However, one species did not evolve from the other species. Rather, about 5 million years ago, modern apes and humans had a common ancestor which was not ape, nor human, nor monkey.

For a brief explanation of the Man from Monkey misconception see #6 at this link: http://www.bio.ilstu.edu/Armstrong/misconceptions.doc

back to top


Content Benchmark L.12.D.1

Students know organisms can be classified based on evolutionary relationships. E/S

Sample Test Questions

1st Item specification: Use evolutionary relationships to classify organisms.

Depth of Knowledge Level 1

  1. The science of naming and classifying organisms is
    1. taxonomy.
    2. taxidermy.
    3. phylogeny.
    4. morphology.
  1. The evolutionary history of an organism is known as its
    1. taxonomy.
    2. phylogeny.
    3. philosophy.
    4. morphology.
  1. A horse and a donkey may interbreed with each other and produce offspring, but the offspring are sterile. This occurs because the horse and the donkey belong to a different
    1. species.
    2. genus.
    3. class.
    4. kingdom.
  1. Based on their scientific names, the cats Felis concolor and Felis catus belong to the same
    1. species.
    2. genus.
    3. class.
    4. kingdom.
  1. What characteristic do all organisms have in common?
    1. They contain a nucleus and membrane-bound organelles.
    2. They are genetically identical.
    3. They use DNA to pass on genetic information.
    4. They are composed of many cells.
  1. Which of the following will most likely provide the best data for determining the phylogeny of three very closely related species?
    1. Comparing their anatomical structures
    2. Investigating their scientific names
    3. Examining their fossil record
    4. Analyzing their DNA

Depth of Knowledge Level 2

  1. A scientist discovered a new organism and noted the following characteristics: It is multicellular, heterotrophic and its cells contain a cell wall. Into what kingdom is the best place to classify this organism?
    1. Fungus
    2. Animalia
    3. Plantae
    4. Protista
  1. The table below shows the taxons of four different animal species.
  Species 1 Species 2 Species 3 Species 4
Kingdom Animalia Animalia Animalia Animalia
Phylum Chordata Chordata Chordata Chordata
Class Mammalia Mammalia Mammalia Mammalia
Order Carnivora Carnivora Carnivora Carnivora
Family Felidae Otariidae Ceridae Felidae
Genus Felis Zalophus Odocoileus Panthera
Species catus californianus virginianus pardus

(Adapted from http://www.nisd.net/secww/science/science-taks/quiz20/classifications%20quiz.htm)

Based upon the information in the table, which two species are most closely related?

  1. Species 1 and 2
  2. Species 1 and 4
  3. Species 2 and 3
  4. Species 2 and 4
  1. Use the diagram below to answer the question that follows.

At what point in time did the most recent common ancestor between the monkeys and the hominoids exist?

  1. 8 million years ago
  2. 14 million years ago
  3. 35 million years ago
  4. 56 million years ago
  1. Use the diagram below to answer the question that follows.

According to the diagram, which two groups of organisms are most closely related?

  1. Frogs and Salamanders
  2. Reptiles and Birds
  3. Birds and Mammals
  4. Mammals and Reptiles
  1. Use the diagram below to answer the question that follows.

According to the diagram, what two species of the Hominidae are the most closely related?

  1. Mandrills and Baboons
  2. Gibbons and Orangutans
  3. Humans and Gorillas
  4. Chimpanzees and Bonobos

back to top


Content Benchmark L.12.D.1

Students know organisms can be classified based on evolutionary relationships. E/S

Answers to Sample Test Questions

  1. A, DOK Level 1
  2. B, DOK Level 1
  3. A, DOK Level 1
  4. B, DOK Level 1
  5. C, DOK Level 1
  6. D, DOK Level 1
  7. A, DOK Level 2
  8. B, DOK Level 2
  9. C, DOK Level 2
  10. B, DOK Level 2
  11. D, DOK Level 2

back to top


Content Benchmark L.12.D.1

Students know organisms can be classified based on evolutionary relationships. E/S

Intervention Strategies and Resources
The following list of intervention strategies and resources will facilitate student understanding of this benchmark.

1. For additional general background on evolution standards for the teacher, see:
National Science Teacher’s Association (NSTA) position statement on evolution: http://www.nsta.org/positionstatement&psid=10

NSTA Questions and Answers regarding evolution, as well as suggestions on how to respond to student questions and oppositions: http://nsta.org/evolutionqanda

To read the National Science Standards Content Standard C, Molecular basis of heredity and Biological evolution pieces. http://www.nap.edu/readingroom/books/nses/6e.html

For additional information on what is recommended in evolution education, see: Evolution on the Front Line: An Abbreviated Guide for Teaching Evolution from Project 2061 at AAAS. http://www.project2061.org/publications/2061 Connections/2006/media/Evo_Handout_Teachers.pdf

2. For good definitions of taxonomy, classification, phylogeny, etc.
http://www.emc.maricopa.edu/faculty/farabee/biobk/BioBookDivers_class.html

3. The University of Arizona has developed “The Tree of Life Web Project.” The goal of the project is to compile an online database about the biodiversity and evolutionary relationships of all organisms. The site contains identification keys, images, phylogenetic trees, and other information as well as links to activities and other useful information. This could be used in the classroom in a number of ways, including giving students the opportunity to study phylogenetic relationships between many organisms. Access it at: http://tolweb.org/tree/phylogeny.html

4. A collaborative project of the University of California Museum of Paleontology and the National Center for Science Education shows students how evolutionary trees are constructed.
http://evolution.berkeley.edu/evolibrary/article/phylogenetics_01

5. Is Classification Arbitrary or Not? This is an introductory lesson that demonstrates how biological classification inherently reflects ancestral relationships. http://www.indiana.edu/~ensiweb/lessons/cl.intro.html

6. PBS has established a valuable resource website with online lessons for teachers and students on Nature of Science, Darwin, Evidence for Evolution, how evolution works, human evolution, ethics involved in evolution education. See specifically:
a. Eight-session professional development course, where you'll examine major evolutionary concepts, explore teaching methodologies, and address obstacles to teaching evolution. http://www.pbs.org/wgbh/evolution/educators/course/index.html

b. Online lessons for students. http://www.pbs.org/wgbh/evolution/educators/index.html

c. Students can build family trees using molecular, embryonic, reproductive, etc. characteristics. http://www.pbs.org/wgbh/evolution/change/family/index.html

7. Students can use a lesson called “Who was Charles Darwin” to learn more about how Darwin arrived at his conclusions http://www.pbs.org/wgbh/evolution/educators/lessons/index.html
Also at this site, video clips and readings from and about Darwin can be accessed http://www.pbs.org/wgbh/evolution/library/02/index.html

8. The Skulls Lab
This is a version of the classic classroom activity in which students compare skulls of different hominids. This activity can demonstrate that documentation of similarities and differences between species helps in the understanding of biological and evolutionary relationships and classification. Excellent skull pictures with key.
http://www.indiana.edu/~ensiweb/lessons/hom.cran.html

9. Charles Darwin’s The Origin of Species can be read online. Teachers and students could use all or parts of the book in discussions about evolutionary relationships between organisms. For the online book, go to:
http://www.literature.org/authors/darwin-charles/the-origin-of-species/

back to top

Benchmark
Support Pages

Misconceptions:
Click Here
Sample Questions:
Click Here

Intervention Strategies & Resources:
Click Here