Earthworm Love Is Cuddly ... and Complicated | Deep Look

Earthworms know a thing or two about romance. They cozy up with a mate inside tubes of slime, then follow a series of intricate steps to make cocoons full of baby worms.

DEEP LOOK is an ultra-HD (4K) short video series created by KQED in San Francisco and presented by PBS Digital Studios. See the unseen at the very edge of our visible world. Explore big scientific mysteries by going incredibly small.

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You can tell an earthworm is ready to mate once it has grown a fleshy patch called a clitellum.

When it sidles up to another earthworm, their bodies point in opposite directions, and the worms surround each other with tubes of slime exuded from their skin.

The earthworms embrace by using flaps on their clitella, and exchange sperm that travels outside their bodies. As they snuggle, the sperm flows into internal storage sacs.

After mating, an earthworm produces a sheath with its clitellum that it shimmies down its body. The protein-rich ring moves over tiny holes, where it gathers eggs and some of the collected sperm. Then, the ring slips off the worm to become a cocoon with one or more developing earthworms inside.

--- How do earthworms help the soil?

Earthworms eat tiny bits of degraded plants, which have bacteria and fungi growing on them. This organic matter might be in the soil or in leaf litter on the surface. Some earthworms eat manure. When they poop out the remains, earthworms make nutrients like nitrogen available for plants to grow.

And the earthworms that live underground spread around their nutritious poop, known as castings.

“Subsoil comes up to the top, topsoil goes down towards the middle or bottom,” said Sam James, who studies earthworms at the University of Iowa. “And you can see the difference in colors of these two layers of soil.”

Earthworms also create channels in the soil through which air and water can move, he added.

--- What is worm composting?

Earthworms such as the species Eisenia fetida can be kept in a bin and fed certain types of food scraps. Using earthworms to dispose of leftovers in this way is also known as vermicomposting.

--- Can earthworms reproduce without sex?

Yes. Some earthworms can reproduce on their own, through a process called parthenogenesis. These earthworms are all mothers — they don’t make sperm, only eggs. Their offspring develop from eggs that divide into identical copies.

“They just clone themselves,” James said. “So what it means is a single individual can start a new population.”

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#earthworm #deeplook

[tanvir_zaman]

I am so confused. I am so revolted yet fascinated. Only Deep Look can evoke these two emotions in equal measure every single time.

[shadowki]

Of course this is their valentine's video 🤣

[efl]

I have had worms for more than 10 years at home in various places: balcony, kitchen and even by my work desk. I have encountered all kinds of worm mating behavior, even self mating. But presenting such simplistic animals with this much detail and clarity even made me curious about their anatomy. Wonderful camera angles and shooting as always, and such demonstrative video!

[Frostyflytrap]

I can't emphasize how surreal it is to see earthworms in such great detail, I used to look at earthworms all the time as a kid and seeing something so familiar in this light feels like putting on glasses for the first time, haha! Amazing work on these shots!

[amberk.]

I was waiting for a "would you still love me if I was a worm?" joke 😂

[Isa-sbjn]

Every date is a blind date for earthworms

[alchemy]

So I have a massive phobia of worms since childhood, especially earthworms (leeches are an exception for some weaird reason I don't know, they're kind of wholesome in a way) yet this topic just felt so interesting that I somehow forced myself to click and watched most of it.
OK, I admit I spent most my times in the comments, but hey, not bad for a start. And the infos were actually super-interesting, as always, so keep up the good work, it was another amazing video.

[joeyjoe]

Okay, this was a weird one! 🤣🤣🤣 But just couldn’t take my eyes off it! Great video as always!

[Lord_Baphomet_]

I feel like we shouldn’t be watching this… those poor worms probably have no idea they were filmed lol

[ISS]

So technically, worms do the funny number.

[thelogician.]

Earthworm took valentine night to next level.

[DavidCruickshank]

I didn't know that worms had such beautifully iridescent skin, amazing video as always!!

[zvzmuye]

i cant believe that i (17) learned how earthworms, such a common animal, reproduce on youtube instead of school
Thank you deep look
and greetings from germany

[mathewho]

The way they reproduce absolutely blew my mind!

[JAZUMIN]

I can’t believe they didn’t teach this in school. I personally don’t like worms but I like learning new things about them. The way the video is presented in this video is also a real huge W, especially because I didn’t feel disgusted at all!! Thanks so much for this🙏

[INTOASECRETLAND]

Earthworms are amazing creatures. They do so much good for the earth.

[beras_jasmine]

I love the
- video quality
-narrator
-soothing voice
and last but not least the Animalssss !

Thanks to all of the DeepLook member !
u guys are amazing !
Lovee from malaysiaa xoxo

[Skohl]

It's not the size of your worm, it's how you wiggle it.

I'll see myself out.

[mekku]

So those are worm egg...
Thank you for showing it, i never seen it in my life :D

[Hyraladen]

I always wanted to know how they mated, and I had no idea this would be the process or how they produced their eggs.
As a kid, Since Earthworms has that ring around them (the Clitellum), I thought Earthworms were the reason we got Ringworms on our skin 😂