The year is 1933, and the world around us is changing, for better and for worse.

King Kong amazes movie audiences. The 21st Amendment ends Prohibition.

And around the corner looms a dark period for the world. Amidst this backdrop, scientists continue to fill the world with wonders, conceiving of astronomical marvels and medical miracles. And as they dive deeper into the invisible world around us, a rare ciliate makes an appearance….

And after an absence of almost 90 years, we’ve found it again. We aren’t in the business of news here at Journey to the Microcosmos. But we do sometimes find something that feels like it should be breaking news.

Like when James, our master of microscopes, manages to find a microbe that hasn’t been spotted since the 1930s— that always gets the rest of us on the Journey to the Microcosmos team excited because we know we’re about to see something weird. And ‘weird’ is exactly what James brought us. The organism that he found is that oval-ish character with a twisted tail at one end.

And that tail ended up making it really difficult for James to get other scientists to believe what he had found. But before we get there, let’s start with how James managed to find this microbe to begin with, which really leads us to a question that you might not think about when you’re walking around: how old is that pond? Now obviously the answer depends

on which pond you’re talking about.

If you live in a city like James does, the ponds you stumble across are much more likely to be on the younger side. And that poses a bit of a conundrum for James in his hunt for his particular microbial specialty: ciliates. Because when it comes to finding hotspots of ciliate diversity, older ponds are much better.

Ciliates can spread to new locations as cysts, which get carried by the wind or animals from one spot to another. So a pond that has been around for a while will probably have welcomed many new residents over the years, building a diverse microscopic neighborhood in the process. There is this one particular lake in Warsaw, though, that's been a curiously rich spot for ciliates, which was surprising to James given how young ponds usually are in cities.

But when he looked through older maps of Warsaw, he found that this pond had been around for at least 130 years, and probably even longer, giving it plenty of time to accumulate more and more ciliates, including rare ones. When James found this organism four years ago, he was so excited to have uncovered what he was sure was a member of the genus Bryophyllum. He’d found so many of them in this pond, and he wanted to be able to learn more from an expert.

So he reached out to someone who works on this genus, sending an email that included images of what he had found and mentioned just how many of them he’d found. But when he heard back, the expert simply told him that the ciliate he’d found was damaged— that the weird tail wasn’t actually a tail, it was just something wrong with the sample he collected. And that response was discouraging, especially given how many other individuals like this James had found.

But our Master of Microscopes is nothing if not persistent, so he returned to the pond. And on his way, he posted about his hunt for a rare ciliate on Instagram. And then he got a response from the ciliate expert Professor Genoveva Esteban, who has since become one of James’ main collaborators.

Though at the time, they were just acquaintances. Professor Esteban asked James what he was on the hunt for, and he sent her the picture of the tailed ciliate, it blew her mind. She had never seen anything like it in her long years of exploring the microcosmos, but she was able to uncover a German paper from 1933 by a Professor J.

V. Gelei. And when James looked through the illustrations in the paper, he found his tailed ciliate.

It wasn’t damaged at all— it was just so rare that the last report of one went back decades. It was tricky, but James was able to identify the species as Bryophyllum caudatum by looking at specific patterns where the cilia roots into the plasma membrane. These patterns are really hard to see with a light microscope, James was just able to make out those identifying details with his.

It was frustrating though to try and convince others of what he’d found. Even though he kept his samples in a large tank and kept turning up more tailed Bryophyllum, one of the scientists he talked to insisted that there was no actual tail. That what he was seeing was maybe some kind of remnant of how he pipetted his samples onto the slide— that James was stretching and deforming the cell into forming a tail-like structure.

James just rolled his eyes and made a handheld microscope to watch the Bryophyllum in action in the tank. And there he could see several of them swimming around on the sediment, their tails very much present without James’ intervention. And that means the Bryophyllum he found were not damaged— they were just a perfect combination of weird and rare that does make them hard to believe.

Tails are not a common trait among ciliates. And even more strangely, James found that the length of the tail seemed to vary from individual to individual. Given how rare Bryophyllum are, it’s hard to establish exactly what the purpose of their tail is.

But James has a few ideas. One is that the tail might be involved in helping the organism survive in low-oxygen areas, increasing the Bryophyllum’s surface area so that they can take in more oxygen. So individuals that live in areas with lower oxygen concentrations would have a longer tail.

But the tail might also help Bryophyllum eat, because it’s lined with extrusomes, which are organelles that can be fired off to paralyze food. In this case, we can see the Bryophyllum paralyzing rotifers and turning them into food. And here is a well-fed Bryophyllum, stuffed with rotifers.

When James was telling us about his experience with the Bryophyllum caudatum, the thing that stood out to him most was how challenging it was to convince people of its existence, and how formative Professor Esteban’s belief in what he’d found was. She didn’t discourage him. Instead she hunted, digging through old texts with the same persistence that James shows with old city ponds.

Unfortunately, despite years of encounters, the Bryophyllum seem to have disappeared from the pond. But who knows, maybe they’ll turn up there again, or in some distant pond. And when someone finds it and isn’t sure of what they found, we hope they can at least find this video— a letter from a past microscopist who believes in them.

Thank you for coming on this journey with us as we explore the unseen world that surrounds us. Given the fact that you just watched this entire video, we’re going to go ahead and assume that you enjoy learning on YouTube. Well, did you know that you can actually earn college credit for doing that?

You see, the company that produces Journey To The Microcosmos also produces a lot of other shows, and one of those shows is Study Hall, a channel that lets you start taking college courses right here on YouTube! Here’s how it works: You watch the course videos on the Study Hall channel for free, and then sign up for an online college course led by ASU faculty for just $25 and apply what you have learned. If at the end of the course you’re happy with your grade, pay $400 (which is about a third of the cost of a college credit!) and now you have 3 transferable college credits on your transcript!

Whether you’re trying to learn new skills, earn college credit, or just prove to yourself that you can do it, Study Hall may help you reach your goals without the financial risk! You can pick between common gen-ed college courses like Modern World History, Human Communication, and more on the Study Hall channel! Check out GoStudyHall.com or click the link in the description to learn more.

The names on the screen right now, those are our Patreon patrons. They're the people who make it possible for us to continue on this journey. Just think of this.

When you first heard that a ciliate had been found that hadn't been seen in 90 years, did you think that it was our Master of Microscopes who would have found it? I bet you didn't. But it was and that's one of the reasons I think what we do here is pretty special.

If you want to help us out, you can go to Patreon.com/JourneytoMicro. If you want to see more from our Master of Microscopes, James Weiss, you can check out Jam & Germs on Instagram. And if you want to see more from us, there's probably a subscribe button somewhere nearby.