The Whippet #160: Make a fish expert angry today

Listen, I have bad news about Interpol and in particular about being an Interpol agent and hunting down international jewel thieves in an exhilarating game of cat-and-mouse.*

There's no such thing as Interpol agents! There's barely such a thing as Interpol! It's all fake! (I know to some people this will be like "you can't just hit the 'Enhance' button to zoom in on CCTV footage and make it high res" but it was news to me, and this whole newsletter is founded on my hope that if I didn't already know something, a bunch of other people didn't either.)

Anyway, Interpol is more just a facilitation/coordination service that makes it easier for different countries' law enforcement agencies to talk to each other. If you joined Interpol you would be doing admin.

* re: cat-and-mouse, I just looked up Castle of Cagliostro to remind myself of the name of the Interpol officer in it [Inspector Zenigata] and according to the creator, Zenigata was conceived as Lupin's arch-rival to create "a human Tom and Jerry". Ridiculous car chase scene here if you like that sort of thing.

There used to be a shark with a circular-saw jaw

Helicoprion lived a couple hundred million years ago, but we didn't really understand what they looked like until 2013. (At which point we also found out that it's not really a shark, but is in fact in the ratfish family –

Of course, as Leif Tapanila [curator at the Idaho Museum of Natural History] points out, the word “shark” doesn’t have the simple definition we might expect. “‘Shark’ doesn’t have biological meaning anymore,” Tapanila told me, confiding “If I talk to a fish expert, and I say ‘shark,’ they get very angry.” [Geology IN]

– okay so, Interpol not real, sharks not real, I don't know. Moving on:

Sharks and a bunch of other fish have cartilage skeletons, which don't fossilise well. So all they've really found of Helicoprion is fossils of the lower jaw, which look like this:

The discoverers were quickly able to figure out that it wasn't an ammonite or anything, that those were shark teeth. At which point begins a 100+ year history of scientists guessing where on a shark you might put a tooth spiral. Coming off its dorsal fin? At the end of its tail? Maybe its nose ends in a spiral?

This Helicoprion toy for sale on ebay has it on the lower jaw, but it's still not right:

And then in 2013, a student named Jesse Pruitt starts making a nuisance of himself at the Idaho natural history museum:

“He started poking around and asking questions about Helicoprion jaws,” Tapanila says, about “why the jaws were this way and not that.”

Using a CT scan they were able to see inside the fossil, including where scraps of cartilage attached to the bone, proving definitively that the buzzsaw basically was the jaw, rather than being at the end of the jaw.

There's still a lot of mysteries – why it evolved so different from other fish, for one. As of 2020, Tapanila and Pruitt were trying to get their hands on a bigger CT scanner so they could scan an even bigger Helicoprion specimen. [Most of this info and the quotes comes from Geology IN]

PS If you're in Sydney, the museum currently has an exhibition accurately called "Sharks" with a dozen or so to-scale models of various shark species that you can get right up close to, and go, oh my god that is very big (including a Helicoprion, a whale shark, and a great white).

From a study showing that bathing in hotsprings is good for capybaras' skin

This study was done in Japan and I honestly assumed it was going to be funded by a hotsprings operator, but apparently not.

Available to read in full:

Inaka, K. & Kimura, T. (2021). Comfortable and dermatological effects of hot spring bathing provide demonstrative insight into improvement in the rough skin of Capybaras, Scientific Reports 11.

The Names of All Manner of Hounds: 1000+ names for dogs, from a fifteenth-century manuscript

Edward, second duke of York, compiled a list of 1065 dog names. I came across this via weird medieval guys on twitter, who described it as 'names he [Edward] considered to be suitable for dogs' – which I suppose must be right, because he can't have known that many dogs in real life. A few highlights:

• Nosewise
• Garlik
• Pretyman
• Argument
• Best-of-all
• Salmon
• Hosewife
• Trinket
• Havegoodday

You can read the full list here.

A medievalists.net article on pet names tells us that:

Anne Boleyn, one of the wives of King Henry VIII, had a dog named Purkoy, who got its name from the French ‘pourquoi’ because it was very inquisitive.

From an 1504 list of Swiss dogs:

Some dogs got their names from the work being done by their owners: Hemmerli (Little Hammer) belonged to a locksmith, while Speichli (Little Spoke) belonged to a wagoner.

and re: cats

In medieval England domestic cats were known as Gyb – the short form of of Gilbert – and that name was also popular for individual pet cats. Meanwhile in France they were called Tibers or Tibert was generic name fo domestic cat in France – Tibert the Cat was one of the characters in the Reynard the Fox animal fables.

[full article on Medievalists]

Edible Rocks

Just a small selection from Spooky Geology's collection. No source given = source unknown. More at Yummy Rocks Part 1, Yummy Rocks Part 2 and Yummy Rocks Part 3.

Please note I am not a registered dietition; talk to your doctor before adding geology to your diet.

Goal-setting / giving yourself a target to aim for

Ali Abouelatta, a product manager at Duolingo (language-learning app), experimented with adding the following screen after you sign up or end a streak:

There's a whole thread about it, but one main point is that this screen doesn't interact with the rest of the app in any way at all – you pick a streak goal (number of days you think you'll be able to in a row) and, other than remembering the number, the app doesn't do anything with that information whatsoever.

So it's the "setting yourself a target" that seems to do the job. Worth experimenting with for habits that involve a lot of delayed gratification.