Am reading more Mary Roach. Extremely entertaining and informative in a slightly gross way.

I want to check a few of her facts with you. Start with three cow facts.
1) Cows can’t vomit. They do get motion sick but lack the ability to vomit, ditto rabbits.
2) You’ll never see a web video of any enterprising cowhand lighting cow farts or burps, that’s because the methane and hydrogen produced in the cow’s rumen is passed from the rumen to the lungs, is mixed with air in non-flammable amounts and exhaled.
3) The cow’s first stomach, the rumen, contains no gastric juices, but does have extremely powerful muscles. Any animal swallowed by a cow (or by a whale) would die by being crushed to death.

On the topic of dragons, I’ve based my origin of the myth on ancient drawings showing a flying snake not with fire, but instead carrying the Sun in its mouth. Explaining for instance why dragons were supposed to live underground at night and cause earthquakes. Mary Roach has a different take on the origin of the dragon myth, one that ties in with hydrogen produced in the stomach. Summarising her story:

“Snakes don’t produce hydrogen in their stomachs, but rotting prey items build up hydrogen inside after being swallowed whole. When the prey bursts inside the snake, the hydrogen is released in a pulse, and this has been confirmed by scientific measurement. Imagine your friendly caveman has caught a python for dinner and leaves it facing the camp fire. A kick of said python bursts its prey, turning the python into a flame thrower. Hence the origin of the dragon myth.”

Pet food manufacturers face a number of challenges. One produces what is loosely called “crack for cats”, it is used as a coating for the otherwise totally repulsive (to cats) dry cat food. The greatest compliment a dog can pay to dog food is to vomit, if they like it so much that they wolf it down too fast then that’s the result. Dogs like their food flavoured with a little putrescene and cadaverine, but owners don’t because it makes the feces stink; making a dog food that both dogs and owners like both going in and coming out is quite a challenge. Just because a dog initially heads for dog food A over dog food B doesn’t mean they prefer it, it could mean that they like the smell a bit, often dogs are initially attracted to dog food A but will finish off the dog food B first. Gone are the coloured pet-food pieces of the early 1990s, because when it comes back up then you have green and red dye all over your carpet, duh.

Some good quotes from Mary Roach:
“The human digestive tract is like the railway line from Seattle to los Angeles: transit time is about thirty hours, and the scenery on the last leg is pretty monotonous”.
“… that queer little oral stalactite. Its full medical name, and my pen name should I ever branch out to write romance novels, is palatine uvula”.

mollwollfumble said:

I want to check a few of her facts with you. Start with three cow facts.
1) Cows can’t vomit. They do get motion sick but lack the ability to vomit, ditto rabbits.

Possible, but cows regurgitate food for mastication (“chewing their cud”). I’d be surprised if this one is true.

mollwollfumble said:

2) You’ll never see a web video of any enterprising cowhand lighting cow farts or burps, that’s because the methane and hydrogen produced in the cow’s rumen is passed from the rumen to the lungs, is mixed with air in non-flammable amounts and exhaled.

Unlikely. I read a journal article a while ago suggesting that cow flatulence was a major source of methane in the atmosphere, and thus of “greenhouse gases”.

Here are some articles:
Biological Emissions and North-South Politics
Do Cows Pollute As Much As Cars?
From that article:
“Cows emit a massive amount of methane through belching, with a lesser amount through flatulence. Statistics vary regarding how much methane the average dairy cow expels. Some experts say 100 200 liters a day (or about 26 53 gallons per day), while others say it is up to 500 liters (about 132 gallons) a day.”

mollwollfumble said:

3) The cow’s first stomach, the rumen, contains no gastric juices, but does have extremely powerful muscles. Any animal swallowed by a cow (or by a whale) would die by being crushed to death.

The first part, that there are no gastric juices or enzymes in bovine stomachs, is true; they rely on bacterial action. I have no information about the second part, about strong stomach muscles, though.

Wocky said:

mollwollfumble said:

I want to check a few of her facts with you. Start with three cow facts.
1) Cows can’t vomit. They do get motion sick but lack the ability to vomit, ditto rabbits.

Possible, but cows regurgitate food for mastication (“chewing their cud”). I’d be surprised if this one is true.

mollwollfumble said:

2) You’ll never see a web video of any enterprising cowhand lighting cow farts or burps, that’s because the methane and hydrogen produced in the cow’s rumen is passed from the rumen to the lungs, is mixed with air in non-flammable amounts and exhaled.

Unlikely. I read a journal article a while ago suggesting that cow flatulence was a major source of methane in the atmosphere, and thus of “greenhouse gases”.

Here are some articles:
Biological Emissions and North-South Politics
Do Cows Pollute As Much As Cars?
From that article:
“Cows emit a massive amount of methane through belching, with a lesser amount through flatulence. Statistics vary regarding how much methane the average dairy cow expels. Some experts say 100 200 liters a day (or about 26 53 gallons per day), while others say it is up to 500 liters (about 132 gallons) a day.”

mollwollfumble said:

3) The cow’s first stomach, the rumen, contains no gastric juices, but does have extremely powerful muscles. Any animal swallowed by a cow (or by a whale) would die by being crushed to death.

The first part, that there are no gastric juices or enzymes in bovine stomachs, is true; they rely on bacterial action. I have no information about the second part, about strong stomach muscles, though.

Read somewhere on the web that an average of 61%, maximum 94%, of cow methane produced comes out of the lungs. As a result of methane produced in the rumen being absorbed by the blood and then released into the lungs.

On the origin or more correctly an explanation of Dragons ..

https://www.youtube.com/watch?v=sK6tkcxAHIw

skip to about 2.45

mollwollfumble said:

Pet food manufacturers face a number of challenges. Dogs like their food flavoured with a little putrescene and cadaverine, but owners don’t because it makes the feces stink; making a dog food that both dogs and owners like both going in and coming out is quite a challenge.

Dad used to work for Friskies dog food. His department was making dog food for the Japanese market, which is tricky because the Japanese keep their dogs inside 100% of the time; they don’t have backyards. Therefore the challenge was to make a tasty food that would come out somewhat dry and in small lumps so it doesn’t stink or stick to carpets. It’s also available here; the brand is Alpo (IIRC).