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Do you remember when Pokemon Go came out?

We were all walking around with our phones held up to catch Eevees and Magikarps and. Pikachus wearing Santa hats.

It was a good time, if your phone battery could handle it, because, you know, who doesn't love the idea of exploring their world for invisible, fantastical creatures? For centuries, scientists and explorers have found the same thrill that games like Pokemon. Go elicit by exploring the microcosmos, a very real universe of organisms that overlays and intersects with our surroundings.

But it is not augmented’s actual reality, visible only under a microscope as we examine samples collected from locations near and far. It's an endeavor that has taken to some extreme environments, like Antarctica, to find just what kind of microbe can stake out a life in almost every conceivable situation. But the beauty of the microcosmos is that it is everywhere.

You can examine a nearby puddle or hike to a distant lake, and there the microcosmos will be. It's also an incredibly diverse world of organisms whose contents reflect the location and chemistry of the area you select from. So the chances are high that any time you venture out for more samples, something new to you will float into view under your microscope lens.

Now, before we get to how we collect our samples, let's start with where we get them from. The organisms we showcase on this channel are all aquatic, inhabitants of water that. James, our Master of Microscopes, samples from ponds, lakes, aquariums--just about any accessible watery location that seems promising.

So how do you figure out whether a body of water might be a good microbe hunting ground? One indicator to be on the lookout for is food. Shallow ponds can accumulate leaves and other plant matter, creating a feast for microbes who decompose organic matter for their food.

On these decomposing leaves, you will often find a thin layer of sediment. And inside that sediment is where you will find many a microbe. Here, James is using a transfer pipette to take bits and pieces of that sediment, extracting it from various points around the decaying leaves and gathering it into a collection tube.

Sometimes, he uses a turkey baster instead because sometimes science requires, you know, repurposing other appliances. Other compelling signs of life are biofilms, a mixture of microorganisms that have congregated together into a larger, visible mass like this orange biofilm. It might be a little off-putting to look at, but grossness at a larger scale can obscure the beauty of smaller scales.

Because the area is a bit tough to reach, James adapted another non-scientific tool for his purposes, this time hooking up a collection tube to a selfie stick so that he can grab some of that biofilm for later examination. And there are other tools as well, including this plankton net, which is a cone made of mesh that lets water pass through while trapping organisms inside. Our plankton net has a 20 micron mesh size, so as we pull it out of the water, anything larger than 20 microns will be left behind.

And with every drag through the water, the samples become more and more concentrated with life. And by the time we're done, our samples will have so many organisms that they will deplete the dissolved oxygen in the water very quickly. So when we collect our microbes in this way, we have to check them under the microscope as soon as possible to keep them alive.

There are other signs as well that a pond or lake might be an inspiring microbial source, like a greenish color that suggests an excess of algae. But even though the microscopic life we feature is all aquatic, we don't necessarily have to turn to obvious bodies of water to find them. After all, water is not a guaranteed resource at all times, and a number of microbes have evolved their own mechanisms to survive dry spells.

When water is scarce, these organisms go dormant, forming protective cysts that encase their resting bodies until it rains or some other source of hydration awakens them. These wet-dry cycles can happen over seasons, or just over the course of one day as dew forms and then evaporates. So while we might often focus on ponds and lakes for finding microbes, it turns out that soil, with its periods of wetness, can also give us some exciting results.

To find the microorganisms that live there, we collect the top layer of soil, which is around 5 centimeters deep. We want to make sure the soil is packed with plenty of nutrients, so we might make sure that there’s a lot of plant litter for the organisms inside to dine on. When air-dried, these samples can be stored for years without losing a significant number of the hardy species that reside in the soil.

And when it comes time to awaken our sleeping beauties, we transfer the soil into petri dishes and lightly soak them in some distilled water--not too much though, we don't want to flood the soil. After 48 hours, we will check on the samples by tilting the petri dish and collecting some of the water to look at under the microscope. Of course, these are only a few of the ways people collect microbes.

You might find as you start your own journey that different settings require other means. Like this time James wanted to see what diatoms, ciliates, and flagellates were living in the biofilm formed on beach rocks, so he had to scrape at it. It is the microcosmos after all: it just takes a few steps into nature, some simple tools, and a little creativity.

And the payoff is...well, it’s tiny, but also infinite. Thank you for coming on this journey with us as we explore the unseen world that surrounds us. And thank you of course, and as always, to all of these amazing people whose names are appearing on the screen right now.

If you like Journey to the Microcosmos, these are the people who make it possible. They are our supporters on Patreon. And you can find out how to join them in the description.

If you want to see more from our Master of Microscopes, James check out Jam & Germs on. Instagram. And if you want to see more from us, there’s a bunch of videos just around the corner at