A few weeks ago, I talked about part of my tattoo, but I neglected the blue bird looking thing in the middle of it. Well, gather round and let me tell you the story of how this simple thing became the mascot of linguists around the world.

Now if there were two of them, you would have two _____.

No this is not a trick question, the answer is “wugs”, but think about the sound that you use at the end of it when you say it out loud. The word “wugs” has a “z” sound at the end of it.

Now what if this were called a “heaf” instead. Then it would be an “s” sound at the end of it, right?

What if it was called a gutch? Then we would have a different spelling by inserting a short unstressed vowel (hey, didn’t we talk about those recently?) and calling them gutches.

Now keep in mind that these are all made up words that you have likely never seen before, but somehow you knew exactly what to do with them. Now you might be saying “okay, so we have plural rules… What’s the big deal?” Well, discovering this back in the 1960’s was a big deal because there was debate among many linguists and psychologists whether we used rules to pluralize nouns, or whether we simply memorized all of the words and their plurals individually.

Think about this in simpler terms. Imagine that your brain has a library of all the words it knows stored on file cards, and we can call it a lexicon. Researchers at the time were unsure whether people had two separate file cards for things like “dog” and “dogs”, or whether we just have the file card for the word “dog” and there is some universal rule we can apply to this that lets us know what sound to make when we pluralize it.

From an organizational standpoint, it is much cleaner to imagine the latter scenario here, but this test (known as “the wug test”) now gave us a unique way to prove it by asking children what they would do.

In 1958, an article published by Dr. Jean Berko Gleason introduced the world to these loveable little wugs. Like I described above, she had presented this test to children and asked them to pluralize words like “wug”, “heaf”, and “gutch”.

The children in this study were divided into two groups, pre-school children and first-grade children. What she found was that first-grade students were significantly more likely to produce the correct forms “wugs”, and while performing highly on words like “heafs” it was not significantly better than the pre-school children. Irregular words like “gutches” had very low performance, but the children will still be able to produce a word like “glasses” which implies that they had not quite learned that rule yet and likely just memorized that particular word.

So, from this test, we can formalize a pattern in English for how we pluralize words. Words that end in a “voiced sound” like dog or mug will get a “z” sound for their plural. Words that end with an “unvoiced sound” like cat or map get an “s” sound. Words that end in a “ch” like sound, like glitch, will have the unstressed vowel inserted as well and have an “es” ending.

Now let’s back up a bit. I introduced a concept in that last paragraph that probably caused some confusion. In any spoken language, the consonant sounds can vary in their voice property making them either voiced or voiceless. Voiced sounds are consonant sounds where your vocal folds are pressed closed together so when the air passes by them, they vibrate. In contrast to this, voiceless sounds are produced with your vocal folds spread apart so the air does not cause them to vibrate.

You can feel this difference when you are speaking by placing your fingers on your esophagus as you say the words “sit” and “zit”. You can feel that when you start the word “sit” that there is no vibration in your throat, but when you say “zit” the “z” sound causes your throat to vibrate a bit.

These properties of the sounds end up affecting the type of plural suffix that gets added to a word, and this just becomes a process that we do automatically without thinking about it. In fact, if you do think really hard about it, and try to produce to word “dogs” with an “s” sound at the end of it, it is actually quite difficult to do.

A word like ‘glitch’ ends up getting the extra vowel added on because it would be a very large cluster of consonant sounds at the end of a word without it. This is the same reason that you may have heard people in your life pronounce the plural of “text” as “textes”. It’s just easier to insert an extra unstressed schwa than it is to try and produce a large sequence of similar consonants in a row.

So there you have it. Because of this simple test done way back in the 1960’s, we now have a cute little bird like thing that we can use to identify ourselves as language nerds by getting it inked into our skin. There are other things that were covered in Dr. Berko’s test related to verb tense, but we will save the past tense work for the future.

Thank you for reading folks! I hope this was informative and interesting to you. Be sure to come back next week for more interesting linguistic insights. If you have any topics that you want to know more about, please reach out and I will do my best to write about them. In the meantime, remember to speak up and give linguists more data.