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Blinkist puts all the need to know information from thousands of nonfiction books and condenses them down into just 15 minutes, and you can go to to learn more. Hi, it’s me, Deboki, back on the Cnidarian beat.

Last time I was here, we explored the terrifying world of a hydra’s tentacles. Today, I’m here to talk about one of their relatives, the starlet sea anemone, also known as Nematostella vectensis. I didn’t know that I’ve spent my entire life mispronouncing “anemone” as “anenome” until I began learning about the starlet sea anemone.

And so, I will often be referring to them as Nematostella throughout this episode. I hope you understand. I can’t fault the starlet sea anemone for its name though.

After all, I have a name that often involves correcting other’s pronunciation. And there’s more to the Nematostella’s life that I feel kinship with, but to get there, I need to start with a question. When you look at the starlet sea anemone, where do you think it’s from?

The water, sure. But water is vast, vaster than land, and it has its own boundaries and geography. So, like, where do you think it’s really from?

We can tell you where this particular individual is from. A lab at the University of Vienna, where it lived until a scientist named Sanjay sent one of his samples to James—our master of microscopes—so that he, and we, could look at them. So thank you, Sanjay.

There are a lot of nematostellas in labs around the world. Their bodies and reproduction are simple, providing us with a means to explore the questions and secrets behind how patterns and layers form in bodies across nature. But before the nematostella ended up in labs, they—or one of their forebears—must have come from somewhere.

But where? The answer should be simple. In 1935, the biologist Thomas Alan Stephenson gathered twenty years worth of work into a two-volume monograph titled “The British Sea Anemones”.

In there lies the first recorded description of the starlet sea anemone, which had been found in a brackish pond on the Isle of Wight . Compared to the organisms we usually focus on, the nematostella is quite large, growing several millimeters in height. But for someone wading through a pond, it’d be easy to overlook.

It’s small, translucent, and a burrower, digging itself into mud and letting its tentacles spill out onto the visible surface. But difficult as the nematostella is to spot, researchers became concerned in the 1980s when their counts of the starlet sea anemone in England began to dwindle. In 1983, the nematostella was classified as a vulnerable species to protect it from extinction.

This is sadly not an uncommon tale when it comes to our interactions with wildlife, and so it’s tempting to leave it here, to allow the starlet sea anemone to become yet another cautionary tale of our environmental misdeeds. And yet. While the species was first described in Britain, it has been found in other parts of the world too, particularly on both the Atlantic and Pacific coasts of North America.

And when scientists counted, there seemed to be plenty of nematostella in these other regions. But there were some weird quirks to these different populations. The English Nematostella population seemed to be completely void of males, like an underwater Themiscyra.

Meanwhile, the population in Nova Scotia seemed to be entirely male. And there didn’t seem to be any environmental explanation for why some populations might be different from the others. So what caused these nematostella to take up at such different locations, and in such different ways?

Boats. For centuries , boats have been traveling the world, taking cargo and passengers alike. And with them have travelled even smaller passengers, including—most likely—the nematostella.

After all, it’s small and hardy, able to survive journeys through the different temperatures and salinities. And most importantly for the traveling nematostella, it can reproduce asexually, dividing to form more versions of itself. This would explain why we might find populations of the starlet sea anemone that are entirely female or entirely male.

That’s just the one that showed up first, the one that made its way to a new home and then filled it with its own clones. Our genes are a map of our ancestor’s lives, and in the case of the nematostella, they’ve helped scientists chart the path the organism likely took. The nematostella in Britain, for example, have very little genetic diversity compared to their New England counterparts, suggesting that the British ones are a more recent transplant.

And using inferences like that, scientists have piece together a story where nematostella made its way from the western Atlantic (or, maybe less confusingly, the east coast of North America), and then travelled the world from there. So the nematostella is not native to Britain. It’s a recent arrival, early in forming its identity.

But when it comes to asking where the starlet sea anemone is from, I’ll be straightforward: it’s hard not to project a little as someone who has been asked that question in its many forms before, and as someone whose home is an amalgamation of the immediate places I’ve lived in, and a city on the other side of the world where I didn’t. Even learning about how the genetic uniformity of certain populations provides us snapshots of the anemone’s journey feels familiar. Immigration and diasporas are complex and nuanced, so there’s no way to generalize from my own experience.

But an idea that I heard once and that has stuck with me when I understand my Indian American experience is this notion that first and second generations like me tend to carry our family’s country of origin with us from a certain point of time, so that the traditions and rituals we choose to maintain in this new home tie us together while also inevitably dating us. Often, when you’re a first or second generation immigrant in America, your journey is framed in terms of tension: of a tension between who claims you, and who you claim. I hate thinking in these terms, even when it feels true because I’ve come to realize that as much as these claims are impactful, they can also be arbitrary, shifting with the currents and climate and location.

If it’s a question of where I belong, the answer will always be conditional, and that’s frustrating. Defining the Nematostella’s origins is conditional as well, dependent upon the asker’s aims. But the Nematostella is not an immigrant, and I have no desire to compare the entirety of the immigrant experience and its human realities to an anemone.

As a question of conservation though, the nematostella’s origins become significant. In England, where our understanding of the species originated, the populations are dwindling. But the efforts to protect it are built more on earlier assumptions that the nematostella is a native species, which we know now it is not.

But we also know that whenever the nematostella arrived at its new home, it took to it, and without causing further harm to its local ecology. In the early 2000s, scientists argued that while we may not need to introduce populations of nematostella to its British locations, it is still worth protecting the ones that are already there. So where is the nematostella from?

Well, it depends. And this time, I find that kind of beautiful. Thank you for coming on this journey with us as we explore the unseen world that surrounds us.

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