Thanks to Skillshare for supporting this episode of Journey to the Microcosmos. The
first 1,000 people to click the link in the description can get
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You've probably gone through something like this before. You have a loaf of bread sitting around,
waiting to be eaten. And you fully intend to eat it, you might even have had the perfect sandwich
in mind. But then you go grab some slices and you notice that someone…or something…got to it first.
It’s the mold, the dreaded hairy patches of black, blue,
green, and gray expanding like a circular lawn intent on taking over your bread.
It seems to come out of nowhere, but once it arrives, there is no getting rid of it.
If you’ve been following our journey through the microcosmos for a while now, you might remember
that we talked about slime molds before. So maybe it seems to you that we have covered mold already.
Except that when it comes to nature, it turns out that historically, humans have
not been so great at naming things, which is not entirely our fault. We have, for obvious reasons,
tended to use similar names to describe organisms that look similar to each other.
And slime molds kind of resemble bread mold, with the way they both fly around the world
as small spores, and the way that they both creep and spread across surfaces. But this
resemblance hides some pretty big differences. For example, a slime mold is a protozoan,
which means that the large organism you see is actually a single-celled eukaryote
able to push the boundaries of its one cell further and further and further.
Mold, regular old mold, like the kind you see on bread,
are not anything like that. They are an entirely different kingdom, in fact. They... are fungi.
And there are a few fungal species that are known to make up bread mold specifically,
the most common of which are the multicellular Rhizopus, Penicillium, and Cladosporium2.
As we said, fungi are their own kingdom of life, just like protozoans and plants. But
while their growth and way of life might make them sometimes resemble members of other kingdoms
like plants and protozoans, it turns out fungi are the animal’s kingdom’s closest relations3
Of course, family relations mean nothing when there’s food on the table. And fungi
are not like us. They can’t just go to the store to pick up a loaf of bread. They can
however travel, flying through air or swimming through water as spores. These spores are kind of
like seeds, waiting for the right combination of temperature, acidity, and moisture to take root.
And for some lucky spores, bread can potentially provide those conditions.
Especially pre-sliced bread, which has all those nutritious nooks and crannies to grow in.
And mold are very good at growing. Starting from the spore, the fungus begins to expand in the
form of threads called hyphae. The hyphae grow at the tips, their walls made out of the tough but
flexible chitin that allows them to get creative. Sometimes the hyphae form branches of their own,
and sometimes they will fuse with one another. The result is a web of hyphae called the mycelium.
But the mycelium is not just a matter of spreading. It’s a network that acts
as a feeding apparatus. The hyphae will secrete enzymes into the bread around it, breaking down
its nutrients so that the fungus can eat. It’s basically just a really large network of mouths.
This makes for a frustrating sight when we’re looking at our despondent,
gross slices of bread. But when you see a piece of mold growing and eating away at a piece of bread,
you are seeing a loose approximation of the same processes that made our world possible.
We’ve seen this before with lichen, a collaboration between fungi and algae that
breaks down rocks into the mineral components that sustain other forms of life. And fungi
can break down so much more. There are even species in Chernobyl, eating away
at radioactive material like hot graphite Fungi, they could eat the world, if they
wanted to. But their path is much more subtle than their fuzzy appearance might suggest.
Because fungi don’t just tear things apart. They also form relationships—significant,
essential relationships—with other organisms. A plant’s roots, for example, might become
intimately entwined with a fungi’s hyphae, forming a bond we call the mycorrhiza.
And as fungi hook themselves up to different plants, they can connect the plants themselves,
serving as living bridges to exchange everything from nutrients to chemical warning messages.
So it is tempting, when writing about fungi, to treat them as something that needs to be
redeemed. After all, for many of us, fungi are the thing that rots. They put an end
to our bread, our fruits, and our snacks. And It’s so easy to redeem them when they
clear the world for us. When the bread mold that disgusts us also famously supplied us with
penicillin, an antibiotic that after its accidental discovery in mold
went on to save countless lives. But fungi, however prevalent they may be,
are a challenge to pin down. In his book Entangled Life, the mycologist Merlin Sheldrake writes,
“I have tried to find ways to enjoy the ambiguities that fungi present, but it’s
not always easy to be comfortable in the space created by open questions. Agoraphobia can set in.
It’s tempting to hide in small rooms built from quick answers. I have done my best to hold back.”
Ambiguity is not difficult to find in nature, especially when we’re venturing
into the microcosmos. These are organisms that speak to a world that long pre-dates us,
and in their enduring nature, they suggest a bit of what the world may look like after us.
Thank you for coming on this journey with us as we explore the unseen world that surrounds us.
And we’d like to also say thank you to Skillshare for supporting this video.
If you’re looking for a more aesthetically pleasing way to bring fungus into your home,
you can check out the “Sculpt your Own Mushrooms” course on skillshare.
Host Stephanie Kilgast will guide you along as you use polymer clay to sculpt and then paint
three different kinds of fungus for a fantastic desktop display. It’s a fun project that can
be done in a couple of hours and there are no special skills required so you can start making
your own mushrooms right now! And there are tons of easy to start classes like this on Skillshare.
Skillshare is an online learning community that offers membership with meaning. With so much to
explore, real world projects to create, and the support of fellow-creatives, Skillshare empowers
you to accomplish real growth. It’s curated specifically for learning, meaning there are no
ads to distract you, and they’re always launching new premium classes, so you can stay focused
and follow wherever your creativity takes you. And an annual subscription to Skillshare
is less than $10 a month. If you’re one of the first 1,000 people to click the
link in the description, you can get a free trial of Skillshare’s Premium Membership.
The people on the screen right now, well they are our Patreon patrons. Every single one of them is
like a delightful little fungal spore implanting itself in the fertile ground of the microcosmos
and then stretching their mycorrhizae out and secreting digestive enzymes into our creative
brains so that we can continue to pump out good microcosmos content. If you want to
become one of those delightful spores, I don’t know if this is a good pitch or not, regardless,
you can go to patreon.com/journeytomicro If you want to see more from our master of
microscopes James Weiss, check out Jam & Germs on Instagram. And if you want to see more from us,
there’s always a subscribe button somewhere nearby.