Scale, Proportion, and Quantity

Scale, Proportion, and Quantity

Science studies stuff from an itty-bitty atom-small scale to a massive universe-big scale, and everything in between. What exactly is a scale, though? Aside from being the thing we avoid standing on after the holidays, a scale is a range that shows us how things relate to one another. For example, we can use a scale to compare size, strength, quality, or even time.

Before a scientist can hop on the experiment train, they need to understand exactly what it is they're studying and on what scale they're going to be studying it. Let's take bacteria, for example. They're small, usually thought of as gross, and they're all over everything. Let's say our friend the bacteriologist wants to know more about these little guys. The bacteriologist is going to first have to decide what scale she wants to look at.

Does she want to stick to a small scale and study the bacteria themselves? Or does she want to zoom out a bit and understand how bacteria work in the small intestine? Or should she zoom out even farther to understand how intestinal bacteria differ in various countries throughout the world? Understanding the scale we want to look at gives us a better chance of answering our experimental question and not getting lost in the details or stuck in the stars.

Scale doesn't just have to do with size, either. We could be talking about a timescale or how much energy something uses. Think about studying the life cycle of a tsetse fly versus studying all of evolution. Or the energy used by a 40-watt light bulb versus a star. Those are some very different scales.

In order to understand scale, we might need to throw a little math at it. This is where proportion and quantity come in. Proportion is the relationship between parts to each other or to a whole. For example, the proportion of the pizza we ate last night is relatively small if we compare it with all of the pizza in the whole world. Proportion is awesome because it allows scientists to zoom in and out relatively easily. They can use proportions to apply what they've learned on a small scale to a larger scale situation. Or if big to small is their jam, proportion works there too.

Then there's quantity. Quantity is basically how much of something we have. This is a favorite observation to make, mostly because knowing how much of something you have is pretty important for understanding scale and proportion, and eventually studying changes. Imagine that we were asked to see how warmer temperatures have affected how many salmon are born in a specific stream this year. Now imagine we don't know how many salmon were born last year. Kind of makes answering how the birth rate has changed, um, impossible.

Understanding scale, proportion, and quantity are crucial to scientists as they conduct their experiments and attempt to answer questions. After all, we wouldn't use a Band-Aid to cover a bullet hole; why would we use magnifying glass to study the sun?