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The Whippet #152: Omnivores vs Cucinivores

McKinley Valentine — 14 min read

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Good morning!

My life update is I have a gold tooth and I'm so chuffed about it. It's a molar so you can only see it when I'm at maximum grin, and then ✨glint✨

I don't necessarily recommend getting a botched root canal, but should that happen, it turns out a gold tooth isn't much more expensive than a tooth-coloured one. You can just ask for one!

Also the dentist was so pleased, I don't think he gets many opportunities to do them.

There is an Australian expression I've always loved, "flash as a rat with a gold tooth" (or "slick as a rat with a gold tooth") –

flash as a rat with a gold tooth
Ostentatious, showy and a bit too flashily dressed. This phrase is usually used of a man, and implies that although he may be well-dressed and well-groomed, there is also something a bit dodgy about him. In spite of a superficial smartness, he is not to be trusted. In spite of the gold tooth, he is still a rat. First recorded in the 1970s.

1978 Sun-Herald (Sydney), 27 August: Eddie is the ultimate lurk-man ... Eddie is as flash as a rat with a gold tooth.

2006 D. McNab, Dodger: What brought him unstuck were his brazen schemes and lavish lifestyle. He was as flash as a rat with a gold tooth.

from Australia National University's glossary of Aus. words

Now I am the rat 😊

(No photo; I have a lot of US readers and your perfect white teeth intimidate me. I gaze upon them with fear and respect.)

'Articles' icon

Huge omnivore news! News about a huge omnivore!

Specifically, scientists have discovered whale sharks are omnivores, making them the world's largest omnivore and knocking the Kodiak Bear off its illegitimate throne.

whale shark wearing a crown
who needs DALL-E

So whale sharks going around scooping up krill and everything else that's around the krill, you know this.

“These are very big animals and when you’re a huge animal you need lots of food,” he said.

“But it costs lots of energy to push their mouths – open like a huge net – through the water. When you get a gut full of food but there’s also a lot of algae what do you?

“Do you throw it up? Energetically that’s a very costly thing to do because you’ve just spent all this energy collecting it.

(Mark Meekan, interviewed in The Guardian)

So obviously, you learn to digest it. Or rather, whale sharks with a mutation that let them digest a bit of seaweed bred more than the ones that couldn't, and then the whales that inherited that trait bred more, blablabla evolution. (Also TIL seaweed is a type of algae – "macroalgae" aka big algae. Whale sharks specifically eat sargassum, the seaweed you find in the Sargasso Sea.)

[more detail in Cosmos]

A counter-scientist said that, just because seaweed gets caught up in their feeding doesn't make them omnivores – you wouldn't call a cow an omnivore because it catches up some ants when it's eating grass.

But the researchers analysed tissue samples and found that they're actually not even metabolising the krill that well. Seaweed might even be a more important part of their diet.

I need DALL-E but they won't give it to me!! This is courtesy of a friend: "kodiak bear falling off an ornate golden throne".

PS if you didn't like the bit about the researchers taking tissue samples from whale sharks:

Meekan says most whale sharks don’t react when they get jabbed by the spear, which is roughly the width of a pinky finger. Some even seem to enjoy attention from researchers, he says. It’s as though they think: “This isn’t threatening. In fact, I quite like that.”

[Science News]

More omnivore news: the Carnivore Diet people are right about some stuff

A sentence likely to annoy both fans and opponents, but anyway, bear with me. And if you don't care at all about the carnivore diet, you might still find this interesting because I'm using it as a reference point to talk about how the body works.

[The pure carnivore diet is eating nothing but meat, salt and water; some people add fish, eggs, some herbs and spices to cook the meat with, but basically it's just meat. It is mainly used by people in an attempt to treat a chronic illness, and also people who want to lose weight.]

You know Reefer Madness? Telling kids that weed will immediately send them insane and destroy their life is the worst way to keep kids off drugs, because they try it or know someone who has, realise you lied to them, and then don't believe you when you say "smoking weed while you're still a teenager can cause problems with your brain development, try not to go too heavy on it."

Being dishonest about the positive aspects of something that you're trying to warn people away from has never been a good strategy.

If you tell carnivore diet people that it's bad and ridiculous in every way and has no benefits, but they've been on it for a week and feel much better, they're not going to listen to another thing you say.

The carnivore diet probably is curing people's gum disease

Starch and sugar do damage to your teeth quicker than meat and fat (or rather, the bacteria that eat starch and sugar do damage more quickly). Also, a lot of people sip sugary and acidic drinks throughout the day, whereas very few people sip meat in between meals. If the person was drinking soda, then removing it from the diet is gonna help a lot, but even just removing all if they weren't, removing all starch and sugar from your diet will make it easier to maintain your dental health. So that's probably a real effect.

People probably are losing weight on the carnivore diet, mostly because it's unappetising

First: carbs are stored in your muscles and liver as glycogen, and to be stored that way, they have to cling to a water molecule. When you stop eating carbs, or cut down, you stop storing glycogen and the water molecules are released. So everyone is gonna drop a couple of kilos when they start the carnivore diet. (This is also true of keto, Atkins, and anything where you're reducing calories overall, since that probably includes eating less carbs). It's really tragic; I've seen diet forums of people miserable because they lost weight "so fast" in the first two weeks, and now it's not working any more and they hate themselves for it.

Second: it's just hard to eat as much food when you're eating meat-with-nothing for every meal, because it's bland and same-y, it's not tempting. (Protein is more satiating than carbs or fat, but that tops out at well before you've converted your entire diet to protein. So someone going from a high-protein diet to an all-protein diet won't see any changes there, and if it's an effect you want, you don't need to cut out all fruits and vegetables to get it.)

It's also a negative: if you're trying to build muscle, the carnivore diet would make it tougher, because it would be harder to eat enough calories and your muscles would be glycogen-depleted (yes yes ketones, I know. I'm not saying it's impossible, just tougher, which is relevant because meat evangelists tend to associate it with hypermasculinity).

I have to explain how the digestive system works but it's interesting and not gross

This is going to be a bit reductive, biologists don't @me.

You basically have two main digestive processes. One is an enzyme-based one, which starts with saliva, and continues in stages through your stomach and your small intestine. The second is your microbiome, a symbiotic bacteria colony that lives only in your large intestine (there's a valve to stop the bacteria growing up into your small intestine). (I said this was reductive – I've already missed the part where your teeth grind stuff up.)

So your enzyme system digests fat and protein, and breaks starches up into simpler sugars that can be absorbed into your blood stream.

(Bile isn't an enzyme, it's like soap – an emulsifier. It allows fat/oil and water to mix, so the water-based enzymes can get into everything.)

Your large intestine and its symbiotic bacteria colony partially breaks down fibre, and creates gas during the process – it's literally fermentation. The process creates short-chain fatty acids which are good for your digestive system, and makes the environment acidic so toxic bacteria can't live there.

This is the important part: in a healthy person, you are meant to get a bit bloated after eating. That is your microbiome doing its job properly.

In someone with IBS – that is, around 15% of the population – your intestine is super sensitive, and it freaks out when it notices the bloating, get inflamed, spasms, cramps, shuts things down, speeds things up, brings on nausea, etc. (This is true of some other, less common digestive illnesses as well.)

Carnivores vs herbivores
True carnivores, like cats, have a very simple, very fast digestive system with a pitiful microbiome. (This is why they can eat rotting meat when we can't – the food passes through too quickly for the bacteria to take a hold in their system.)

Cows with their four stomachs have multiple microbiomes that they cycle food through; even a single-stomach herbivore like a rabbit has a little extra digestive pouch called a coecum [pr. seek 'em, as in "Coecum? I 'ardly knew 'em."]. The coecum contains a very well-developed bacteria colony that the rabbit can leave grass with to digest.

Humans are in-between: we have a complex, slow digestive system but our coecum is vestigial. We can eat neither rotting meat nor grass.
"Comparisons of digestive tract anatomy". The wider post-stomach sections are the bacteria colony sections.

The above is from a paper arguing that, since our digestive tract is much shorter than a pig's (an omnivore often considered the closest model for humans), we should actually more properly called "cucinivores" – eaters of cooked food. Eg we have weak jaws that would be ineffective for eating exclusively raw and unprocessed foods. I don't know if that's valid, but I thought it was interesting.

Comment from biology-degree-having Tom Lang, who I ran this section* by:
"It [herbivores using bacteria colonies to digest cellulose] is classic ecological niche stuff. The more difficult and annoying it is to survive in a certain way – eating grass, eating gumleaves, eating volcanic sulfur compounds, surviving in the desert – the more of an advantage it is if you can do it. ANYONE can eat berries and grubs! So it's not worth putting on your evolutionary resume."

* He only looked over it for the animal biology stuff, he does not wish to be held accountable for the human diet stuff.

not that he precisely said "McKinley, please tell them to hold me accountable for the animal biology stuff" either

So yeah, anything incorrect in this issue is my fault, not his. You can leave me a comment about it by clicking the button below:


The carnivore diet really does help digestive illness (in the short term)

Since you're cutting out 100% of fibre, there is nothing for your microbiome to eat and no gas is produced. If you've got the idea in your head that you're never supposed to be bloated, that will (incorrectly) feel healthier to you. If you have IBS, your intestine won't be freaking out, and you will feel a LOT better. People who switch to the carnivore diet are likely to be in less pain within a week or two.

However, you are also killing off your microbiome by starving it, and not producing short-chain fatty acids. This is very bad for your digestive system in the long term.

Jordan Peterson among others have anecdotes about going on the carnivore diet for a year, then having a bite of an apple, and being completely messed up by it. They use this as evidence of how bad apples are for you. Again, this is probably not psychosomatic. After that long period eating nothing but meat, they no longer have the bacteria to properly digest fruit.

(Note that most 'real world' carnivores do actually need a little bit of vegetable matter, but they get it from eating herbivores whole, including their stomach contents. Humans on the carnivore diet don't do this. They're also less likely to eat organ meat, which has a tonne of minerals and vitamins that you really need if you're not eating plants and aren't a scurvy enthusiast.)

An alternative to the carnivore diet if that still sounds tempting because you're really suffering

The low-FODMAP diet, developed by Monash University, restricts the most gas-causing fruits and vegetables – it's a sort of compromise, it does some damage to your pet bacteria colony, in exchange for huge improvements to quality of life. If you think you might have IBS, you should try it; if you don't, you should not try it, it is a less healthy diet overall.

(There's a pretty steep learning curve, but even just cutting out garlic, onion and wheat would make a big difference, so don't feel like there's no point if you can't do it perfectly. It won't cure your gingivitis though.)

Oh yeah, non-coeliac "gluten-sensitive" people aren't making it up

Wheat contains a lot of fructans, which are one of the highly fermentable sugars that make IBS worse. So someone tries a gluten-free diet, their symptoms get much better because they've cut out wheat fructans, and they assume it's the gluten, because after all, they were on a gluten-free diet. This is not ridiculous. It's a pretty decently scientific attitude to approaching your diet/health interactions, even if it's incorrect in the specifics.

There might be other elements of the wheat that people are reacting to as well – plants are complex and made up of a lot of different chemicals.

Be nice: chronic illness is dismissed by the medical system, and people are desperate

If you were miserable and in pain, and you went to the doctor, and they were like ¯\_(ツ)_/¯  or "have you tried mindfulness" or implied that you're exaggerating your pain or imagining it

and you'd tried all the usual exercise and diet stuff (remember that a good diet for a healthy person — fresh vegetables! – can aggravate symptoms for an unhealthy person)

you would be willing to give anything a go. Even if you were 99% sure it was snake oil – if it wasn't toxic, and you could afford it, you'd take that 1% gamble.

And since symptoms fluctuate, yours might get a little better when you happened to be trying the latest snake oil. Can you really blame someone for taking more when it correlated with an improvement in their symptoms – for recommending it to their fellow sufferers?

You want people to stop falling for wellness grifters, start with the institutions that have failed them, not with the desperate sick people.

(Fun fact, snake oil – that is, oil from Chinese water snakes – is genuinely anti-inflammatory, because it's high in Omega-3. But US medicine show folks switched to locally obtainable rattlesnake oil, which isn't, and then to mineral oil with a picture of a snake on the label, which isn't anything.)


More whale shark news!! They are delightful and secretive guys!

No one has ever seen a whale shark give birth:
“How can you have an informed conservation plan for an animal if you don’t know how, when or where it breeds?” asked Alistair Dove, the vice-president of research and conservation at the Georgia Aquarium in Atlanta, US.
Their childhoods are shrouded in mystery:
“There’s a sort of lost years period, between when they’re born at about 45–60cm long, until they’re up to about 3–4 metres long. That period in between there, we don’t know where they are.”
DALL-E: "A whale shark character as a delinquent teen smoking a cigarette"

(alternatively, the whale shark lifecycle includes several years on land working as a carpenter)

They dive incredibly deep, for no apparent advantage:
Green and his team also tagged several of the animals, only to find out that they often dive beyond the 2,000-metre range of the tags. He and his team have been at pains to explain this “spiralling behaviour”, as the deep water dives seemingly confer little advantage in escaping predators, birthing pups or finding the plankton that whale sharks mostly feed on.

You can sense the researchers' exasperation,

One whale shark they tagged, Anne, travelled over 20,000 km (12,000 mi) from Panama to the Mariana Trench.

That's not really mysterious, but it does make them tricky to study. So big, but still so hard to find!

Lastly, and I'm very sorry about this:

Whale sharks have tiny teeth on their eyeballs

[Do your own google image search, I'm not putting myself through that]

Their eyes are covered in "dermal denticles", armour made of tiny tiny teeth the shape of an oakleaf. They can also retract their eyeballs. Scientists assumed whale sharks – like other sharks – navigate by smell, but putting so much effort into defending their eyeballs suggests their eyeballs must be very precious to them, and might be their main navigation sense. [Smithsonian]


Optical illusion: What if some people were taller than others?

Forgive my unfair title, this is actually amazing. Even if you've seen an Ames Room before, the execution is excellent:

full 3-minute video is on youtube

Unsolicited Advice

Get the first try out of the way

I really like this framing from Jonathan Vieker. The first time you try something, you're going to be garbage at it anyway. So instead of spending a tonne of time learning and preparing in the hopes of making a decent go on it, just accept it'll be trash and do it.

It's specifically that phrasing of "get it out of the way", which is the opposite of the typically recommended 'mindfully engaging with every experience in the present moment' that I appreciate. It's so dismissive! That's the attitude you need to overcome perfectionism.

Although saying that, I know there are people who prefer to learn boardgames by just diving straight in without reading the rules, and figuring it out as they go along. This is baffling to me – how can you get started if you don't know the rules? Just put your pieces wherever you like based on vibes?? I like to read all the rules first – I won't remember all, or even most of them, but it gives me a mental framework to hang things on.

So let's call it an approach to experiment with, rather than "this is how you, personally, should approach things." But that's all advice anyway.


Thanks for reading!

Oh here's a proper comments button. The other one just goes to the regular comments section as well, but maybe it makes you feel bad to click it.

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