Directions for teachers: At the end of scientific or engineering investigations, a claim or conclusion is made about the question or problem explored. A successful claim is supported by sound, relevant evidence and reasoning that clearly links the evidence to the claim based on known scientific concepts.

This discussion will focus on identifying and evaluating a claim, evidence and reasoning reported in the Science News article “Climate change may raise the risk of deadly fungal infections in humans. One species already is a threat.” The article presents the view of a group of scientists that fungi in a warming world will pose a greater danger to people. Either for homework or in class, ask students to read the Science News article and split students into groups. If needed, review the concepts of the claims, evidence, reasoning model and let students discuss and answer the first set of questions. Then give students your preferred claim, evidence, reasoning rubric (you can find one online by searching “claim, evidence, reasoning rubric”), and let them explore this U.S. Centers for Disease Control and Prevention webpage to answer the second set of questions and create a claim of their own. Finally, if time permits in class or for homework, have students apply the questions to a Science News article of their choice.

For more educator resources on critical analysis, check out the June 8, 2019 educator guide, “Just the facts.”

Directions for students:

Identify: Use the article to discuss and answer the following questions.

1. A claim is an assertion of something as a fact, which may or may not be supported by evidence. What is one scientific claim made by the scientists as described by the article?

Candida auris is emerging as a new fungal disease with the help of climate change.

2. Claims often serve as answers to questions. What scientific question might the scientists’ claim attempt to answer?

Why does pathogenic versions of C. auris now have the ability to replicate inside people?

3. Evidence is the scientific data that are given to support a claim. What information does the article give as evidence?

The genetic differences of pathogenic strains found on different continents. The year U.S. infections were first reported and the number of infections since then. The number of countries that have reported cases. A note about an experiment where other fungi have been coaxed to grow in warmer laboratory conditions.

4. Reasoning is the explanation of why the evidence supports the claim. What reasoning is given in the article?

There are a few statements of reasoning that loosely relate the evidence back to the scientists’ claim. One is that because the infectious C. auris strains on different continents are not closely related genetically, infected travelers couldn’t have spread the fungus.

Rate and revise: Along with the questions below, use the claims, evidence and reasoning rubric provided by your teacher to analyze and rate the scientific argument reported in the article. Next, explore the Centers for Disease Control and Prevention’s webpage titled “General Information about Candida auris” to suggest a new claim that can be adequately supported with evidence and reasoning.

1. How well does the claim answer the scientific question you identified? Explain your reasoning and rate the claim using the rubric provided.

The claim may be a plausible explanation for the scientific question. If similar environmental conditions due to climate change existed on the different continents where infectious strains appeared, those strains may have independently gained the ability to thrive in warmer conditions. Ratings will vary depending on the rubric used.   

2. Does the evidence provided do an adequate job of supporting the claim scientifically? Why or why not? Rate the evidence using the rubric provided.

The evidence given weakly supports the claim. Lab-based experiments provide some evidence that a fungus can adapt to grow in warmer conditions. But the findings are not fully explained, and the evidence does not conclusively prove the claim or rule out alternate claims. Ratings will vary depending on the rubric used.

3. Does the reasoning clearly link the evidence to the claim using known scientific principles? Explain and highlight any missing links in the reasoning. Rate the reasoning using the rubric provided.

No. Though the claim is based on sufficient scientific principles in genetics, reasoning that links the emergence of the fungal disease to climate change is not fully supported by the evidence. The scientists reason that C. auris has proliferated in humans because it has become tolerant of warmer temperatures but does not provide evidence that this tolerance is due to climate change. Ratings will vary depending on the rubric used.

4. Are there other plausible claims that could explain the scientific question you identified? Explain, and give an example.

Yes. Variations of C. auris may have become tolerant to the average human body temperature from an environmental factor that was not directly related to climate change, or from an error that occurred during DNA replication that offered an advantage.   

5. What additional evidence could be given or explored to support the claim?

Shifts in temperature and other environmental factors due to climate change should be documented in affected countries. Other data on how fungi grow in warmer laboratory conditions should be collected, and the genetic profiles of these fungi should be explored.

6. What types of scientific background knowledge would be useful to further explore the scientists’ claim?

Knowledge of genetics, mycology, climatology and human physiology would all be useful fields to further explore the scientists’ claim.

7. Based on your answers above and the information provided on the CDC website titled “General Information about Candida auris,” write a new claim and make a statement of evidence and reasoning.

Claim: The number of U.S. cases of C. auris infections will continue to increase.

Evidence: The CDC reports that C. auris is multidrug resistant, difficult to identify using standard laboratory methods and causes outbreaks in hospital settings. The number of confirmed cases of C. auris infections in the United States has increased since 2016.

Reasoning: Due to the lack of prevention and treatment measures as outlined by the CDC,
C. auris will likely continue to spread, which will lead to more infected people.      

Compare: Select a news article of your choice from the Science News archive, read it and review it using the prompts above. Then compare the news article with the Science News article “Climate change may raise the risk of deadly fungal infections in humans. One species already is a threat.” Note that the story is categorized as a “soapbox.” Soapboxes have historically been used as informal platforms to stand on while giving speeches.

1.  Explain the similarities and differences of the scientific explanation given in each article. How do you think this relates to how the articles are labeled?

Student answers will vary. Students that compare the Soapbox article with a news story might note that the Soapbox presents a hypothesis or viewpoint whereas the news story presents a scientific finding. The Soapbox article is labeled as such because it serves as a platform for scientists to present their hypothesis. While the hypothesis may be well-educated and argued based on special knowledge and existing evidence, it has not yet been tested.