Scientific recommendations change & why that’s a good thing

“I don’t understand why people don’t get the importance of wearing a mask. The science behind the masks has evolved. As scientists learn more, they change recommendations. That is how science works. It’s recommended that we wear a mask now.”

-- my Dad, in reference to the CDC’s recommendations to wear a mask to prevent the spread of COVID-19

These words from my father were spoken in frustration on a trip home from the grocery store where he found himself the sole patron donning a mask. You might be thinking: “The CDC said before not to wear masks but now recommends wearing them. How can this be if science is not wrong?!”

As a graduate research student, I feel confident in sharing with you that science is constantly evolving. The safety recommendations to prevent the spread of COVID-19 have changed as more information and data come to light. But my father wondered why this process isn’t better understood in the general, non-science community.

His frustrations echo a sentiment of my own, one that I am sure most scientists and medical professionals share.  

So, Dad, this blog post is for you. 

Science is all about data. Researchers collect, organize and analyze data and submit formal papers to journals based on those data. Before publication, journal reviewers who are experts in the field review the content of the paper, including the quality, presentation and interpretation of the data.

Science is constantly evolving. (...)
My father wondered why this process isn’t better understood in the general, non-science community. His frustrations echo a sentiment of my own, one that I am sure most scientists and medical professionals share.

Take this ecological example. Let’s say I'm studying breeding frog populations in the Pacific Northwest and submit my results on how breeding rates change in response to urban development. My paper could be reviewed by frog experts, environmental experts or both. These experts would then give me criticism and feedback. The paper could be accepted outright, accepted with minor or major revisions or rejected outright. Revision might include heading back to the writing table to redo sections or performing more experiments and collecting more data to support my claims. 

Let’s say I resubmit the paper with the revisions and it is accepted! Woo! I have contributed to the scientific community! Policymakers can use my science to help make decisions about urban development while also keeping the best interests of frog species in mind. A win-win, right? 

Whether it be two weeks, two months or two years, another researcher will likely expand upon my frog paper. Maybe his or her findings will support my initial claims and improve upon them, offering new and improved insight to policymakers to better help save the frogs. Maybe the findings will not align directly with my initial claims. Over time, things will change and the addition of novel breeding data might point us in a new direction. Policymakers will be given different safety recommendations on how best to care for frog breeding grounds. This is the ever-changing nature of science, and either outcome should be valued. 

If you are skeptical of my frog example, let me share with you two “real life” instances of how scientific theory and recommendations have changed. 

 Geocentrism to Heliocentrism

Once upon a time, humans thought the earth was the center of the universe. From the perspective of someone on earth, that makes sense, right? The earth does not appear to be moving, but the sun and stars appear to revolve around us. This was an idea called geocentrism that was supported by Aristotle (382 -  322 BC) and Ptolemy (c100 – c170). Not until 1540 did Copernicus debunk the notion by providing a mathematical model to support heliocentrism: the idea that the sun is the center of our solar system.  With new evidence, scientific knowledge changed. 

Miasma to Germ Theory

For much of human history, it was thought that miasma, or “bad air,” caused disease. Ancient Europe and China blamed miasma for the horrible nature of diseases such as cholera and the Black Death. 

Microbes were not visualized until the 1670s when Leeuwenhoek, the “father of microbiology,” used his microscope to describe “little animalcules” living in water. Leeuwenhoek’s findings were the beginnings of Germ Theory, or the idea that microbes (like bacteria) cause disease. 

Now back to my frog example. Replace the frogs with yourself and the research recommendations for urban development with the CDC’s mask recommendations. Like new guidelines that would be produced over time to better save the frogs, the new guidelines from the CDC better protect us and the loved ones around us. 

Given time, new experiments and new data, the field of science will evolve. What is recommended today may not be the same as what is recommended next week. Why? Because with time comes more information. 

Stay informed, stay safe, and for my father’s sanity, Wear A Mask.