ACT Science: Conflicting Viewpoints

The second type of ACT Science passage you will see on test day is Conflicting Viewpoints. In these passages, several different viewpoints or hypotheses will be presented on a specific scientific phenomenon. The first few paragraphs will describe the phenomenon and the remaining paragraphs will outline each student or scientist’s viewpoint. These passages typically contain more words than Research Summaries and Data Interpretation passages so your Reading skills will definitely be useful here! Let’s look at some tips for handling Conflicting Viewpoints:

  • Identify the phenomenon

    This is usually located in the very first paragraph. What is the main subject the students or scientists are studying? This frequently will include unfamiliar scientific terminology but don’t panic! Any new vocabulary will be defined by the passage. Locate and underline the phenomenon before you move on to the viewpoints.

  • Understand the basic theories

    Each student or scientist will have a basic theory in regards to the phenomenon. This is usually the first sentence underneath their name. Try and put yourself in each scientist’s shoes. Ask yourself, how are the basic theories different? How are they similar, if at all? Underline these as well so you can easily reference them later.

  • Circle the support

    Once you’ve located and underlined the basic theories of each scientist, identify what they are using to support their theory. Are there any graphs or figures involved? Make sure to draw on the figure exactly what is described by each theory and label it “Student 1”, “Student 2,” etc. Consider whether any of the supporting date is contradictory. For example, if Student 2’s theory is correct, does that make Student 3’s theory incorrect? If no support is provided for a theory, make sure to write “No Support” next to the paragraph.

The main goal of Conflicting Viewpoints passages is to understand what the argument or conflict is about and what is different about each of the points-of-view. As you carefully read and understand the phenomenon, basic theories, and support, it is also helpful to consider what are the strengths and weaknesses of each argument. What needs to be true in order for each theory to be correct? What assumptions are the scientists making?
You may find yourself taking a little more time than usual on Science passages to understand all of the viewpoints before you get to the questions. Make sure you get plenty of practice with Conflicting Viewpoints before your test so you are comfortable and confident with the format. You may feel more pressure on the Science test in terms of timing, but don’t skim on the Conflicting Viewpoints passages – you’ll need to truly understand each viewpoint to answer each question correctly!
Remember to start practicing now for the ACT Science test! Even if Reading and Science aren’t your strongest subjects, you can still raise your score dramatically with careful practice. Now let’s take a look at an example Conflicting Viewpoints question.

Example Conflicting Viewpoints Question

As you read each passage, look closely for keywords that help you identify the author’s opinions. What does the author like? What does he criticize? What adjectives and adverbs does he use to describe the various scientific topics? He may feel positively about one thing, and negatively about another. Feel free to use smiley faces or positive and negative symbols on your ACT Science practice questions to help summarize the author’s point of view. Don’t feel like you have to take extensive, detailed notes.

Two scientists are discussing possible origins of human life on earth. While they agree that the earliest fossil evidence is that modern humans first appeared in Africa 130,000 years ago and there is evidence of modern humans in the Near East approximately 90,000 years ago, they do not agree on the path that led to the evolution of modern humans. During the process of evolution, mutations of DNA appear in offspring. While many mutations are harmful and detrimental to the individual, a few may be helpful in the survival of that individual. DNA coding for useful traits is passed on to offspring and over very long periods of time enough of these DNA changes will accumulate for the group of organisms to have evolved into a different species.
Scientist 1
The evolution of the “modern” humans, Homo sapiens was a result of parallel evolution from populations of Homo erectus and an intermediary of some sort. This process occurred in Africa, Europe and Asia with some genetic intermixing among some members of these populations. There is clear anatomical evidence for this theory when comparing certain minor anatomical structures of Homo erectus populations with modern humans from these areas. These anatomical differences are so minor, this is clear evidence that modern humans must have evolved separately in Africa, Europe and Asia. This is the “Multi-Generational Hypothesis.”
Scientist 2
If one looks at the evidence carefully, the only logical explanation is that a fairly small isolated population of people eventually evolved into the modern Homo sapiens. It is this population that would eventually spread across Asia, Africa and Europe. As they spread, they displaced and replaced other humanoid populations. When one looks at DNA evidence of living humans, especially that of mitochondrial DNA, and mutation rate of DNA one can calculate when modern humans diverged from a common ancestor. Most of these calculations are approximately 200,000 years ago, which is much too recent for the hypothesis of Scientist 1 to be true. Molecular biology also suggests that the first modern humans evolved in Africa. This is the “Out of Africa Hypothesis.”

Scientist 1 believes in “parallel evolution” and uses “anatomical evidence” to support the theory. Scientist 2 believes in the theory of an evolved “small isolated population” and uses “DNA evidence” to support the theory. Scientist 2 criticizes Scientist 1 by saying that 1’s hypothesis is “much too recent.” Now that we have a strong grasp on the foundation for each point of view, let’s check out the question.

Example Question

Which of the following best states the basis for the belief of Scientist 1?
A                  Molecular changes are more important than anatomical differences
B                  Molecular changes are less important than anatomical differences
C                  Molecular changes are more important than anatomical similarities
D                  Molecular changes are less important than anatomical similarities
We have already determined that “anatomical evidence” supports the theory, so we can eliminate A and C since those would support Scientist 2. Referring back to the passage, we can see that the scientist states: “These anatomical differences are so minor, this is clear evidence that modern humans must have evolved separately in Africa, Europe and Asia.” Clearly, Scientist 1’s focus is on the “differences.” The answer is B.