Turns Out, Sea Urchins Like To Use Shells As Hats, So People 3D-Print Them Some Cool Ones

Interview

If you’ve ever seen a sea urchin—you know what a peculiar, cool-looking little dude this echinoderm is. There are a whopping 950 species living on the seabed, making themselves at home in virtually all oceans and depth zones. But it turns out, these little spiky balls also exhibit covering behavior, which means that they use their tube feet and spines to move objects like shells, stones, and other ocean goodness around. And this is just one part of the story.

One Twitter user and biologist posted on Twitter that “I was today years old when I learned that sea urchins naturally use shells as hats to make them feel safer and camouflaged so some aquarists had the genius idea to make them tiny hats,” and it blew up with 18.6K likes and 4.1K retweets.

You heard it right. Tiny, 3D-printed hats for sea urchins are a new must-have among echinoderms, which make them look ten times more stylish, and a thousand times cuter. Some even say they protect their spiky bodies from UV rays, so it’s a win, win, and win!

This Twitter user has recently posted about the tiny hats for sea urchins and it blew up on social media

Turns Out, Sea Urchins Like To Use Shells As Hats, So People 3D-Print Them Some Cool Ones

Image credits: ok_girlfriend

And they look like the most stylish spiky balls out there

Turns Out, Sea Urchins Like To Use Shells As Hats, So People 3D-Print Them Some Cool Ones

Image credits: ok_girlfriend

Turns Out, Sea Urchins Like To Use Shells As Hats, So People 3D-Print Them Some Cool Ones

Image credits: ok_girlfriend

To find out more about this cute project, Bored Panda reached out to the Reddit user u/VanillaBean5813 who shared it on the r/crafts subreddit. “Our sea urchins like to cover their heads, so we 3D-printed them some hats,” the redditor posted the photos of their sea urchins sporting hats 3 months ago.

u/VanillaBean5813, who preferred to stay anonymous, said that this is their family project. “My dad is the real aquarist (and also a redditor), I modify 3D models from the internet, and my mom runs the 3D printer.”

Meanwhile, sea urchins in the wild are sporting makeshift coverings of shells and stones

Turns Out, Sea Urchins Like To Use Shells As Hats, So People 3D-Print Them Some Cool Ones

Image credits: ok_girlfriend

Turns Out, Sea Urchins Like To Use Shells As Hats, So People 3D-Print Them Some Cool Ones

Image credits: ok_girlfriend

The idea was initially posted in this subreddit by a person claiming they 3D-printed some hats

Turns Out, Sea Urchins Like To Use Shells As Hats, So People 3D-Print Them Some Cool Ones

Image credits: VanillaBean5813

The redditor explained that the project started when the family got their first baby corals and the “sea urchins started carrying them away, which is damaging to them.”

After the initial hat designs, they had several improvements. “We went through a few iterations of hats—we learned that hollow structures were too floaty and that caused them to lose the witches hat we made.”

u/VanillaBean5813 said that it’s not entirely clear why sea urchins like to cover their heads. “We think it’s either a defense mechanism for their vulnerable backsides or protection from tank lights.”

Turns Out, Sea Urchins Like To Use Shells As Hats, So People 3D-Print Them Some Cool Ones

Image credits: VanillaBean5813

Turns Out, Sea Urchins Like To Use Shells As Hats, So People 3D-Print Them Some Cool Ones

Image credits: VanillaBean5813

Turns Out, Sea Urchins Like To Use Shells As Hats, So People 3D-Print Them Some Cool Ones

Image credits: letsgetsalty

To find out more about whether scientists would approve of sea urchin hats, Bored Panda also talked to Emma Verling, a senior post-doctoral researcher at MaREI Centre for Marine and Renewable Energy. She conducted PhD research on the covering behavior of the sea urchin species Paracentrotus lividus twenty years ago.

Emma confirmed that some sea urchins do indeed use shells (and other types of objects like stones, leaves, or algae) to cover themselves. However, the reason for such behavior is unknown.

Many of the theories are certainly plausible, for example: that covering acts as a ballast to weigh down the urchins and prevent them from being washed away in heavy surges or winter storms; that the items provide a mechanical protection from predators; that covering may provide a visual camouflage of sorts from predators; that covering protects the urchins from being damaged by UV light, etc.

By the end of her research, Emma came to a conclusion that “different species may cover for different reasons, even that it might confer a number of benefits (such as UV, camouflage, or ballast) simultaneously to varying degrees.”

And it turns out, sea urchin hats come in all shapes and sizes

Turns Out, Sea Urchins Like To Use Shells As Hats, So People 3D-Print Them Some Cool Ones

Image credits: riosouza

Turns Out, Sea Urchins Like To Use Shells As Hats, So People 3D-Print Them Some Cool Ones

Image credits: riosouza

Turns Out, Sea Urchins Like To Use Shells As Hats, So People 3D-Print Them Some Cool Ones

Image credits: riosouza

When it comes to tiny hats for sea urchins, Emma said: “I think the 3D hats are a fun idea, a great talking point, and a way to educate people as to the complex ecology of sea urchins… I honestly don’t see that they could do any harm in an aquarium setting.”

Having said that, Emma was wondering if they “will confer an actual benefit—this is the most interesting and also the most complex of your questions.”

“If covering prevents an urchin from sub-lethal effects of UV such as reduced overall health and reproductive ability, then those that cover more often would logically be more likely to survive into the next generation and their offspring would also be genetically more likely to cover. Over time, the proportion of individual sea urchins that cover would increase because they have a survivorship advantage (this is a very brief summary of evolutionary theory in general!)”

Turns Out, Sea Urchins Like To Use Shells As Hats, So People 3D-Print Them Some Cool Ones

Image credits: riosouza

Turns Out, Sea Urchins Like To Use Shells As Hats, So People 3D-Print Them Some Cool Ones

Image credits: riosouza

Turns Out, Sea Urchins Like To Use Shells As Hats, So People 3D-Print Them Some Cool Ones

Image credits: riosouza

Emma concluded that although the UV theory is a lovely one, the difficulty is that “many different urchin species display covering, including, for example, some species in the deep sea, where not a shred of UV light enters. So why do those species cover—surely it cannot be to protect themselves from UV?” In the end, there’s no easy answer, as is usual with science.

Turns Out, Sea Urchins Like To Use Shells As Hats, So People 3D-Print Them Some Cool Ones

Image credits: riosouza

Turns Out, Sea Urchins Like To Use Shells As Hats, So People 3D-Print Them Some Cool Ones

Image credits: riosouza

Turns Out, Sea Urchins Like To Use Shells As Hats, So People 3D-Print Them Some Cool Ones

Image credits: commander-ledi

Turns Out, Sea Urchins Like To Use Shells As Hats, So People 3D-Print Them Some Cool Ones

Image credits: www.reef2reef.com

People on social media just couldn’t get enough of this cute idea

Turns Out, Sea Urchins Like To Use Shells As Hats, So People 3D-Print Them Some Cool Ones

Image credits: jenndesalle

Turns Out, Sea Urchins Like To Use Shells As Hats, So People 3D-Print Them Some Cool Ones

Image credits: Miss_Jasbutts

Turns Out, Sea Urchins Like To Use Shells As Hats, So People 3D-Print Them Some Cool Ones

Image credits: Miss_Jasbutts

Turns Out, Sea Urchins Like To Use Shells As Hats, So People 3D-Print Them Some Cool Ones

Image credits: thegallowboob

One commenter pointed out their cool hats make a rather poor camouflage

Turns Out, Sea Urchins Like To Use Shells As Hats, So People 3D-Print Them Some Cool Ones

Image credits: TeacherMorrison

Turns Out, Sea Urchins Like To Use Shells As Hats, So People 3D-Print Them Some Cool Ones

Image credits: TheJayTucker

Turns Out, Sea Urchins Like To Use Shells As Hats, So People 3D-Print Them Some Cool Ones

Image credits: thereisnorule6

Turns Out, Sea Urchins Like To Use Shells As Hats, So People 3D-Print Them Some Cool Ones

Image credits: tjlavoie

Turns Out, Sea Urchins Like To Use Shells As Hats, So People 3D-Print Them Some Cool Ones

Image credits: shrimpliker

Turns Out, Sea Urchins Like To Use Shells As Hats, So People 3D-Print Them Some Cool Ones

Image credits: Elvaphant

Turns Out, Sea Urchins Like To Use Shells As Hats, So People 3D-Print Them Some Cool Ones

Image credits: AmyWasp

Liucija Adomaite is a creative mind with years of experience in copywriting. She has a dynamic set of experiences from advertising, academia, and journalism. This time, she has set out on a journey to investigate the ways in which we communicate ideas on a large scale. Her current mission is to find a magic formula for how to make ideas, news, and other such things spread like a virus.

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I'm the Visual Editor at Bored Panda, responsible for ensuring that everything our audience sees is top-notch and well-researched. What I love most about my job? Discovering new things about the world and immersing myself in exceptional photography and art.

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