Sources of scientific information

Look at the diagram: it distinguishes primary sources from secondary sources, but the four examples marked with "?" are waiting to be classified. Explain the difference between a primary source and a secondary source, and classify the four examples from the diagram: a research paper in which a team describes its own experiment, a textbook, a popular science video, and an encyclopedia entry.

Explain what it means for a source of information to be reliable, and give two examples of reliable sources and two of unreliable sources for doing a science project.

Wikipedia is an encyclopedia written by thousands of volunteers. Explain whether it is a primary or a secondary source, what risks using it has, and two strategies for making good use of it in a project (looking at the article's references, cross-checking the information in another source).

Scientific teams publish their results in journals and present them at conferences. Give two reasons why communicating results is an essential part of the scientific method.

Before being published, scientific papers undergo peer review. Explain what this process consists of and what assurances it provides to the rest of the scientific community.

Until 2006 books said the solar system had nine planets; since then they say eight, because Pluto was reclassified. Explain what this case teaches us about the importance of the date of sources and about how scientific knowledge changes.

You are looking for information about vaccines and find two websites: the official page of a health organisation, signed by specialists and with references, and an anonymous blog full of adverts for "natural remedies". Explain which is more reliable by pointing out three specific clues (authorship, publication date, references, commercial interests).

A headline announces: "Science proves that chocolate makes you slim". State three pieces of information about the original study that the news item should give in order to judge it (who did it, with how many people and under what conditions, where it was published) and explain why each one matters.

The same finding is headlined in one newspaper "A small advance could help treat Alzheimer's in the future" and in another "Miracle cure for Alzheimer's discovered!". Compare both headlines: which devices the sensationalist one uses, what effect it produces on the reader, and which one fits real scientific work better.

An advertisement sells a bracelet that "rebalances the body's energy" and is "endorsed by thousands of satisfied users". Identify at least three signs of pseudoscience in this message and explain what evidence you would demand before believing its effects.

A soft drinks company funds a study concluding that sugar does not contribute to obesity. Reason why this funding requires the study to be examined more carefully, and name three things you would check regarding its design and who paid for it.

A very popular documentary states: “Humans only use 10% of their brain capacity; if we managed to activate the remaining 90% through mental training, we would have extraordinary abilities such as telepathy or photographic memory.” The author claims that his hypothesis is valid because “no one has proven in a laboratory that it is impossible to use more than 10%.”

1. a) Refute this myth by providing two biological arguments based on the functioning of the body: one related to the high energy consumption of brain tissue (it consumes about 20% of the body's total energy) and another with medical observations regarding brain injuries.
2. b) In scientific research, the principle of the “burden of proof” applies. Explain what mistake the author makes when stating that his hypothesis is valid as long as the contrary is not proven.