Eels are fish

I had the same thought. I always knew they were fish but always assumed they were local fresh water fish. I mean everyone talks about how Salmon does this incredible journey. If there was another species which did something equally incredible I should have heard about it.

Thanks for the link! A rabbit hole indeed.

Recommend "The Truth About Animals" by Lucy Code [0]. It has good chapter on eels. They take a left and go to the USA or take a right and go to Europe.

[0] https://www.goodreads.com/book/show/34211802-the-unexpected-...

Of all the information in the Wikipedia article the fact that eels are fish was about the least interesting and only thing I previously knew.

I learnt this for my German fishing license. I was really baffled.

Eels are weird as fk, and much of what they're up to is still a mystery from what I understand.

Oh, but you should not classify living beings according to their habitat and behaviour; classification based on the degree of the phylogenetical relationship is obviously superior and the only truly reasonble one.

They also taste like fish lol.

If not fish, why fish-shaped?

It's a brilliant title. I thought: huh, surely that's not a surprise? If that's a surprise, there must be more to eels than I know - which of course is what the article is actually about. If the title was just "eels have an interesting life cycle, actually", I probably wouldn't have realised how interesting it actually was.

QI said (roll podcast title) There is no such thing as a fish, since that group is unbelievably diverse.

Strange that birds are dinosaurs, while Pterosaurs are not. Where is the bipedal fish that looks like a reptile or mamal, but is secretely a fish, too?

I know that the lampreys are often lumped in with the fish, but the jawed fish are more closely related to us than to lampreys.

(Fish aren't a clade at all so call em whatever you want.)

Wait what...Earthworms??

morray seems to be muscian, you mean moray

I mean, in this case who else should do it? If a fish in your local waters goes from relative abundance to critically endangered, who else but the government is supposed to step in?

Thanks. I was wondering about how they got into lakes and bodies of water not connected to the sea.

Was hoping there was some secret underground tunnels connecting all bodies of water.

Same with lampreys. It was quite a surprise when I found one slithering around in my yard.

I'm curious - are you allergic to both bony and cartiligenous fish?

I don’t understand why you thought they weren’t fish. How is that possible?

"The Book of Eels" touched a lot of topics you mentioned, not sure about the witch bit though. It was published in 2020 so probably not the one you are looking for. https://www.goodreads.com/book/show/51938590-the-book-of-eel...

Was it Waterland by Graham Swift (fiction, but has some eel diversions IIRC)?

my favorite online newspaper recently did a long form piece on eels and their decline in Italy ([1] - Italian only, sorry).

The comments mention a couple of books:

- Brian M. Fagan, Fish on Friday

- Patrik Svensson, The Gospel of the Eels (also wrote another book on eels)

maybe it's one of these two!

[1]: https://www.ilpost.it/2025/05/29/anguille-comacchio/

> because the young ones were never seen - only fully grown eels.

Only, as it turns out, per the article the ones you normally see are _not_ fully grown eels; the sexually mature stage is also rarely seen.

They all breed in the Sargasso Sea, so... critical habitat risks.

It also reminds me of a bit in Unsong, a book where there's quite a bit of discussion about whether the whale is a fish or not.

Or humans are fish. You can pick one.

That's crosswordese for you - https://en.wikipedia.org/wiki/Crosswordese - there's also ERNEs, AUKs, TERNs and ORCAs out at sea

Some HN threads on this topic (meaning the "Eel-Rents Project" organized by John Wyatt Greenlee),

https://news.ycombinator.com/item?id=35997727 ("To Pay Rent in Medieval England, Catch Some Eels (atlasobscura.com)", 42 comments)

https://news.ycombinator.com/item?id=25543802 ("Paying Medieval Taxes Using Eels (historiacartarum.org)", 14 comments)

https://news.ycombinator.com/item?id=34284363 ("English Eel-Rents: 10th-17th Centuries (historiacartarum.org)", 12 comments)

> "One enormous transaction shows that Ely Abbey, now known as Ely Cathedral, paid Thorney Abbey 26,275 eels to rent a fen (similar to a wetland),"

Your article left out a neat twist: the name "Ely" is actually derived from the word "eel"!

That's 389

I have extremely strong personal feelings about how confusing Google Maps can be about something eerily similar to this. For several years up until earlier this year, I lived in apartment in Brooklyn that (along with several other apartments) was in a building that happened to be above a deli. The address of the deli was the same as our apartments, but with no apartment number. However, the entrance to get into the apartments was past the end of the deli itself due to having a small lobby area on the ground floor containing the staircase leading up to the apartments, whereas the entrance to the deli was situated very slightly around the corner that it was on, enough that the door essentially looked to be facing outward diagonally in person, but showing up as slightly on the cross street side when looking at google maps. Because the addresses were so similar, we'd sometimes get mail intended for the deli, and I have to imagine some of our stuff sometimes went there.

Frustratingly, Google Maps only considered the deli entrance to actually be the location of our building, and the visualization it gave depicted entering through the door of the deli despite there being absolutely no way to go upstairs from there (even in the areas not accessible to customers; it was fully separated from the apartments themselves). Due to an unfortunate coincidence, an apartment building slightly further around the corner from us had an address with the same number on the cross street (making up numbers here, but essentially our apartment was 123 4th Ave, and the apartment around the corner was 123 56th St). Street View did not have any address shown when viewing the actual entrance of my apartment building; as far as Google Maps was concerned, that door did not belong to any building. Quite frequently, people seemed to trust Google Maps and assume that the entrance must be on the cross street. When we ordered food for delivery, it was not at all uncommon for the delivery people to ignore the instructions I put (which got increasingly attention-grabbing over the years, ending up with several repeated lines in all caps saying "ENTRANCE IS ON <the name of the avenue>" and "DO NOT GO TO <the name of the street>") and ring the doorbell of the apartment around the corner. Once, an entire desk was even delivered outside of that apartment building around the corner (which was quite annoying due to it being quite heavy and that building being downhill from the avenue). This culminated in our neighbor literally storming into our building with the delivery person to yell at me for being an "asshole" for not being able to do anything about this (although they of course had absolutely no interest in listening to anything I had to say, let alone any ideas I had about how we might be able to work together to get this handled better once and for all).

In the aftermath of that incident, I spent a lot of time trying to find ways to get Google Maps to properly show where the entrance of our apartment was. When I tried to contact their support to get this handled, I was informed that they only supported marking a single location as the entrance for a given address, regardless of apartment number (or the lack thereof), and that my only recourse would be to get the city to give my apartment building an entirely separate address. I asked for them to just slightly move the entrance marker over to be on the same street as the entrance to my building, with the rationale that people would still have absolutely no trouble finding the entrance to the deli since they'd be looking at the corner itself and it would be plainly visible, but it would no longer mislead people into thinking that they needed to enter on the cross street, but my request was ignored. I tried giving feedback within the Maps app itself saying that the location of the entrance was incorrect and suggesting a different pin, but unsurprisingly nothing ever seemed to change.

tl;dr Please do not blindly trust Google Maps as a source of truth for the location of an apartment building's entrance in Brooklyn; I have the emotional scars to prove it. (Probably a decent rule of thumb for other cities too, but I don't have firsthand experience anywhere else).

At least you could exclude jawless, cartilaginous, and lobe-finned fish. That would leave you with 99% of what people call fish. But as said it would exclude sharks, they would need to be their own group.

More bothering me is that there are no trees. There are just many plants which have independently evolved a trunk and branches as a way to tower above other plants to compete for sunlight.

For reference, this idea is becoming more popular recently due to the Green brothers: https://youtu.be/-C3lR3pczjo

> Apparently we are all fish. Or fish don't exist

Apparently if you go even further back and apply the same logic, we are all fungi. In fact, we both can synthesize vitamin D from sunlight, although I'm not sure if we do it the same way or use it for the same purpose.

I could be way off base here, and I don't honestly know much about biology... but just because two species don't have recent common ancestors, doesn't mean they couldn't have co-evolved and ended up very similarly, right? Wouldn't this be grounds for relating their classification?

Yes, fish, like trees or reptiles, don't exist as a monophyletic group (or clade).

> things that look like fish

Well, apart from the circularity, we don't look like fish, do we? What we look like, we define, just like we define what 'fish' is. There's no need to go all Linnaeus about it.

This is just a consequence of life beginning in the ocean. Land-based life is related to ocean-based life at the point of the fork, and there were prior forks which, by definition, remained in the ocean.

Does this hold even if we don't include whales and dolphins in "things that look like fish"?

Looking at the Wikipedia article for fish, it looks like a reasonable definition would be:

* Everything in the subphylum vertebrata (i.e. vertibrates)

* Except tetrapoda (tetrapods: amphibians, reptiles, mammals and the like).

It's not perfect because tetrapoda does fit within vertebrata in a biological / genetic sense (as a sibling comment put it: fish is not a monophyletic group). But it's a precise enough definition that I don't think we need to claim that we're all fish or that there's no such thing as a fish (as the QI elves would say).

Fish exist, and we're not fish. Fish just isn't a monophyletic taxonomic category. If you allow "fish" to be a list of all those animals that look like "fish" and swim like "fish", you'll end up with a bunch of animals who's most recent common ancestor is also the most recent common ancestor of all tertrapods (including humans), so "we are all fish". But if you don't demand a single common ancestor & instead just have a list of several different taxonomic classes you can define "fish" as anything in the list, thereby excluding humans.

It's like the difference between culinary berries (sweet parts of plants) and biological berries (parts of plants containing the seeds internally). Tomatoes are not a culinary berry, but are a biological berry. Strawberries are a culinary berry, but not a biological berry (the seeds are on the outside). It's confusion caused by mixing a jargon use of a word with the common use of that same word.

Not a surprising result given that complex sea life significantly predates complex land life. It's had much longer to genetically diversify.

Similarly either we are all black, or black as a genetic race doesn't exist. The genetic diversity within humans in Africa exceeds the diversity outside of it. You can find two "black" Africans that are more genetically different than an Australian aborigine compared to a red headed Irishman.

There's a certain species of ape that takes offense at this, and doesn't like to think of itself as a "fish".

> Apparently we are all fish. Or fish don't exist.

I get very annoyed at this argument. It pretends that the only classification systems are strictly following a single ancestor or ignoring ancestry entirely.

The common definition of fish is neither of these. It's paraphyletic. Everything descended from A, except things descended from B and C.

You should have used "phylogenetic taxonomy". A "taxonomy" is literally any way of grouping organisms, like "all red things" (mature salmon, some roses, red algae).

We are also fairly closely related to fungi, which is why it’s tricky to make good systemic fungicides. They always go after the liver.

Melanin apparently predates the split between fungus and animal kingdoms.

The correct conclusion to take from this is that cladistics supremacists are wrong and there are other valid ways of organising knowledge.

"Lampreys /ˈlæmpreɪz/ (sometimes inaccurately called lamprey eels) are a group of jawless fish"

I'm not sure what you mean? Jawless fish are pretty far from most fish but that's not much of a reason to say they're not fish.

Huh, someone (OP?) will potentially miss the next edition of this newsletter.

I just noticed the URL has a lot of parameters, probably for their analytics to identify the subscriber.

So that cucumber and tomato salad with vinegar dressing... is a fruit salad, as 100% of its ingredients are fruit or processed fruit. (As long as you leave off the onions).