Good morning John. I really admire your dedication to trying to get a bunch of nerds to like sports. That's a lot to take on, and I'll be honest, for a long time, I felt like maybe you were trying a lil’ too hard and like it-it w-wasn't gonna happen. But somehow, hitting me with AFC Wimbledon news every week, even when the news has been very bad, has started to get to me. I guess I'm on this journey with you now and you've been on a bunch of journeys with me as well, so thanks for that. And I'd like to maybe take you on another one.

So far in this video, I've just been showing you a buncha quite boring things, mostly like parts of trees. But I'm gonna bust out my handy jewelers loupe here, which is designed to inspect jewelry but can help you inspect pretty much anything, and see that each of these trees and rocks are actually studded with a bizarre crusting of life.

You probably first heard the word symbiosis when you were in fourth or fifth grade, but no one had ever heard it until 1877 when Albert Bernhard Frank decided we needed a word for something that, at that time, many people did not believe even existed. Now when people started to look at lichen under the microscope, it looked mostly like a bunch of algae, and this wasn't really a mystery. People weren't thinking, “What is lichen?” They were looking at lichen and thinking, “That is like a moss or a fern or a grass or a tree. It's just another kind of plant.” But in the 1860s, like 10 years before Alfred Bernhard Frank coined the term symbiosis, Swiss botanist Simon Schwendener looked at lichen, and he saw among the algae, pretty transparent structures that were to him pretty transparently fungus parts. He started to tell people about this, and people did not agree.

We, as humans, argued for a very long time about this because this was the first organism that did not appear to be only itself. Neither the fungus nor the algae could live apart, but together they became something that was neither fungus nor algae. This is kind of normal for us today, but like the explosion of information that came with the invention of the microscope shattered so many of our understandings of our world and of life on it. They weren't just something else, they were an entirely new kind of organism, a whole new way of existing. And now, we understand that so many things, including our own bodies, exist symbiotically; All while that word itself is less than 150 years old. We are surrounded by infant knowledge that we think has been around forever.

Most days, when I walk down a path in the forest, I'm barely even lookin’ at the trees. I'm mostly thinking about work or worrying about the planet or the people on it or just singin’ a song in my head, but sometimes you look at the trees. And sometimes you look deeper, and now we can dive into what is invisible to our eyes. What a time to be whatever it is we are and to get to observe our world. On every one of those trees is a whole little world that the moment we polished glass carefully enough, we realized broke so many of the rules we thought we knew. It's always there, but for so long totally invisible to us, just doing what works because that's what works.

John, I'll see you on Tuesday.

Also we just released an episode of Journey to the Microcosmos about lichen that inspired this episode. If you want to go deeper on the history and beauty of lichens, it's there waiting for you and in the description. Also, if you want to start on your own journey, we have worked with our master of microscope to create the perfect starter microscope which starts at $350. And it's available at microcosmos.store where there's also a bunch of other cool stuff.