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episode! Go to CuriosityStream.com/microcosmos to start streaming thousands of
documentaries and non fiction TV shows. We’ve spent most of our journey through the
microcosmos seeking out the organisms that are too small to see with the human eye.
The bacteria, the ciliates, the tardigrades. And Part of what makes them so
exciting to find is that they are so tiny. Every moment we spend with one of
these organisms is a peek into something exceptional in our experience of the world,
and it’s the result of how much work James, our master of microscopes, has to put into
hunting down as many microbes as he can. And sometimes, that effort
requires a lot of persistence. Take the creature we’re going to
focus on today: the bristle worm. This has been one of the white whales for our
channel for some time. And as you watch it, you can perhaps understand
why we have been searching so hard for it. It’s got the body of a pipe
cleaner with the head of a cartoon dragon. And maybe you also understand
that just because we’ve been wanting to find one of these worms, that doesn’t
mean we are guaranteed anything. After all, one of the things you have to
accept about the microcosmos, and microbe hunting, is that it is a big world full of tiny creatures,
and it can take a while to find some of them. The fact that we are showing you
one of those bristle worms right now spoils the twist we would usually build
into, but, surprise, we found a bristle worm! The real twist is that this was
not the first bristleworm we found. This was the first bristle worm we found.
Twenty centimeters of segments and bristles climbing up the side of a tank before
burrowing back beneath the sand. Unfortunately, that’s just about all the video
we got of that bristle worm. James spent so much time trying to
find this bristle worm again that he started to feel a connection to it. So
he decided to give it a name: Gunther. James spent hours trying to catch it
without hurting the worm. But Gunther has hundreds of appendages
that can grab onto sand, and James didn’t want to accidentally
snap the worm in half with his tweezers. So instead of showing all the features of Gunther
that we wanted to show, we’re going to show clips of this bristle worm instead because it kind
of resembles Gunther, except a lot tinier. Gunther is hopefully still somewhere in that
tank, living a nice life in the burrow it dug for itself. But it’s hard to know exactly where
in the tank Gunther made its home because it would only show activity in the dark. The moment
James tried to turn the lights on and watch the worm in motion, it would vanish again under the
sand. And as it became harder and harder to find, James kept hoping that one day, something
would bring another bristle worm to him. And then, one day, James received a
package from a coral farm containing sediments and other things that might
contain some interesting organisms. We talked about some of those organisms
that James found in our last episode. But in addition to all of those
organisms, James found several species of his long sought after bristle worm. Bristle worms are also known as polychaetes, and they’re part of the segmented
worm phylum known as Annelids. The name “polychaete” translates in Greek to
“many hairs.” Those stiff hairs are called setae, and for most polychaetes,
they’re attached to paddle-like appendages called the parapodia that
branch off each segment of the worm. Our giant friend Gunther most likely
belongs to the order Eunicida, but its microscopic look-alike is more unknown
to us. But we can imagine that it spends its life crawling around the sand and feeding on
algae, or whatever else it can take a bite out of. You can see this one moving its mouth in
slow motion, like a weird pair of pincers inside clamping down on something, and the
movement is even more dramatic in full speed. This probably looks like a bunch of
tiny individual orange worms tangled together. But it is, in fact, a worm belonging
to the genus Cirratulus that can get to around 12 centimeters in length. And along with
its distinctive color, the worm is easy to spot in wet sandy mud because of those
threads you see waving across your screen. Some of these threads are tentacles,
but others are actually gills. And in the water, those threads seem to float
serenely. But this effect is lost on land. In a paper from the beginning of the 20th
century titled “Notes on the Ecology of Cirratulus tentaculatus,” the author
wrote, “When withdrawn from the mud Cirratulus presents an exceeding
limp and bedraggled appearance.” This worm has a more imposing appearance
but also a funnier name. It belongs to the terebellid order, but it’s known as a spaghetti
worm. These tropical worms live in sand, building tubes out of gravel and limestone to
live in. Their tentacles spill out from the tube, sometimes extending as far as a meter to gather
building materials and food for the worm. To reproduce, spaghetti worms will release their
eggs and sperm into the water, but only at night and sometimes even without other males or females
around. They seem to do this on a lunar cycle, with a limited two week window for these
gametes to release and find each other. That seems like an extraordinarily chance-y way to
reproduce, but it seems to work for this worm. These are the bristle worms we were able
to find from our coral farm samples. And so it seems like our hunt for
this white whale might be over. Except, the more we’ve been reading about
bristle worms, the more we wish we could find even more. Because these are an animal whose
existence seems designed to inspire lists of fun facts and bizarre trivia. There
are thousands of species of polychaetes, and they all seem to have something
remarkable or weird about them. Some spend their lives in tubes that stick up
from the sand, using their parapodia to paddle water through the burrow. Others have managed
to carve out lives near hydrothermal vents. Some sound like they’re straight out of a horror
novel, growing up to ten feet long or dining on the bones of decomposing animals. And some
even have eyes on both ends of their bodies. So knowing that all of these
different species are out there, how could we ever end our quest
for the bristle worm? Thank you for coming on this journey with us as
we explore the unseen world that surrounds us. This episode has been brought to you by Curiosity
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And to balance out all of the creepy crawlies you’ve been watching throughout this
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about the domestication of dogs and how their behavior and anatomy has changed over time to
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now, they are our Patreon patrons. We are so happy and excited to be able to continue our search
of the microcosmos doing weird things like writing to coral companies and having them send us
samples. I think that’s just the beginning of some of the cool stuff we can do, and these patrons
are the reason that we can do it. So thank you so much to all of them, and if you want to become
a patron you can go to Patreon.com/JounreytoMicro. If you want to see more from our
master of microscopes, James Weiss, and why wouldn’t you, check
out Jam & Germs on Instagram, and if you want to see more from us, there is
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