## What-If 0078: "T-Rex Calories"

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The_Alchemist
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### What-If 0078: "T-Rex Calories"

T-Rex Calories

If a T-rex were released in New York City, how many humans/day would it need to consume to get its needed calorie intake?

Tony Schmitz

This is great. It's the first I've laughed at in quite a while. It actually takes quite a bit less to feed a pet T-rex than I figured.

Vertices
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### Re: What-If # 0078 T-Rex Calories

Damn, I really want to see that t-shirt now, but the link is down. xkcd army?

mathmannix
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### Re: What-If 0078: "T-rex Calories"

What about the reverse? How many calories are in a T-rex, and how many burgers could we get out of it? How many Tyrannosaurs would we need to feed all the people in New York City? And what would the ratio be if the two populations, human and dinosaur, reached a delicious equilibrium?

The shirt in question:
Spoiler:
I hear velociraptor tastes like chicken.

Djehutynakht
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### Re: What-If 0078: "T-rex Calories"

mathmannix wrote:What about the reverse? How many calories are in a T-rex, and how many burgers could we get out of it? How many Tyrannosaurs would we need to feed all the people in New York City? And what would the ratio be if the two populations, human and dinosaur, reached a delicious equilibrium?

And also, if we were to replace our meat sources with dinosaurs (*old dinosaurs, not modern day aviary) which would be the most effective in terms of meat production

In short, which dinosaurs would make the best modern day cattle/pigs/chickens/etc?

nowhereman
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### Re: What-If # 0078 T-Rex Calories

Even ignoring the costs of genetic reconstruction in a Jurassic park sort of way, at 80 hamburgers a day (approx \$80 per day) only the rich could afford them. One Tyrannosaur would cost 29,000 per year to feed. Not to mention costs of waste removal, thirty foot high electric fences, and a computing staff that could keep that one disgruntled ex-employee from turning off the electric grid. Perhaps I can afford a velociraptor?
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mathmannix
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### Re: What-If 0078: "T-rex Calories"

Djehutynakht wrote:And also, if we were to replace our meat sources with dinosaurs (*old dinosaurs, not modern day aviary) which would be the most effective in terms of meat production

In short, which dinosaurs would make the best modern day cattle/pigs/chickens/etc?

True... presumably, large dinosaurs such as tyrannosaurs and sauropods would take a great amount of time and/or resources to reach full size. We're probably better off farming velociraptors for their meat, presuming that is ethical.

No one is totally sure what dinosaur metabolism looked like

Spoiler:
Last edited by mathmannix on Tue Jan 07, 2014 6:35 pm UTC, edited 1 time in total.
I hear velociraptor tastes like chicken.

rhomboidal
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### Re: What-If # 0078 T-Rex Calories

So if a massive asteroid impact hadn't killed off the non-avian dinosaurs, junk food-related cardiovascular disease would've caught up with them eventually. Inevitably tragic, really.

The_Alchemist
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### Re: What-If # 0078 T-Rex Calories

Vertices wrote:Damn, I really want to see that t-shirt now, but the link is down. xkcd army?

Any chance you have a script blocker on? I did and it appeared 'down'.

I have the image....but can't figure out how to post it. Help? Does it have to be a link or can I upload it somehow?

We're probably better off farming velociraptors for their meat, presuming that is ethical.

Ever have emu? - it's good, but damn, it can be some tough meat and I bet velocimolpie would be the same. But as velociburger...that might work.

Soup
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### Re: What-If # 0078 T-Rex Calories

The_Alchemist wrote:I have the image....but can't figure out how to post it. Help? Does it have to be a link or can I upload it somehow?

There's an "Upload attachment" tab below the text box on the Reply screen.
Waiting for it...

mathmannix
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### Re: What-If 0078: "T-rex Calories"

Also, I posted it up above, but whatevs.
I hear velociraptor tastes like chicken.

The_Alchemist
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### Re: What-If # 0078 T-Rex Calories

mathmannix wrote:Also, I posted it up above, but whatevs.

Opps. Missed that. Thanks.

And wow to myself. That damn upload attachment hiding in plain sight like that

cellocgw
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### Re: What-If # 0078 T-Rex Calories

nowhereman wrote:Even ignoring the costs of genetic reconstruction in a Jurassic park sort of way, at 80 hamburgers a day (approx \$80 per day) only the rich could afford them. One Tyrannosaur would cost 29,000 per year to feed. Not to mention costs of waste removal, thirty foot high electric fences, and a computing staff that could keep that one disgruntled ex-employee from turning off the electric grid. Perhaps I can afford a velociraptor?

If you fed a T-Rex MickeyD burgers, it'd be dead in a month. What was that movie? Super-size Nation or something like that?
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rmsgrey
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### Re: What-If 0078: "T-rex Calories"

mathmannix wrote:What about the reverse? How many calories are in a T-rex, and how many burgers could we get out of it? How many Tyrannosaurs would we need to feed all the people in New York City? And what would the ratio be if the two populations, human and dinosaur, reached a delicious equilibrium?

The only stable equilibrium where T. rexes eat nothing but humans and humans eat nothing but T. rexes is the one where both populations are 0. The total energy content of a creature is always less than the total energy content of all the food it's eaten to date, so even direct cannibalism, Matrix-style (or otherwise) doesn't allow a non-zero population. Making the cannibalism indirect only makes matters worse.

Jackpot777
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### Re: What-If # 0078 T-Rex Calories

cellocgw wrote:
nowhereman wrote:Even ignoring the costs of genetic reconstruction in a Jurassic park sort of way, at 80 hamburgers a day (approx \$80 per day) only the rich could afford them. One Tyrannosaur would cost 29,000 per year to feed. Not to mention costs of waste removal, thirty foot high electric fences, and a computing staff that could keep that one disgruntled ex-employee from turning off the electric grid. Perhaps I can afford a velociraptor?

If you fed a T-Rex MickeyD burgers, it'd be dead in a month. What was that movie? Super-size Nation or something like that?

Super Size Me? Probably not.

Here's the thing: No one has been able to replicate Spurlock's results, and even basic math disputes the claim that his McDiet consisted of 5,000 calories a day.

As Tom Naughton points out in his documentary, Fat Head, there's simply no way Spurlock could have been eating that much food if he was sticking to his own rules. A large Big Mac meal clocks in at "just" 1,450 calories, and it's by far one of the fattiest items on the menu. This means that even Supersizing lunch and dinner every day and adding dessert falls well short of the 5,000 calories a day Spurlock's nutritionist claims he was consuming. In an effort to find out just exactly what the hell, Naughton attempted to contact Spurlock to obtain his food log, but Spurlock (who makes a huge deal in his documentary about McDonald's never calling him back) never called him back.

Meanwhile, researchers from the Making Sure Movies Aren't Stupid department of Sweden's University of Linkoping tried to replicate Spurlock's experiment by tasking healthy college students with the challenge of eating 6,000 calories of fast food per day, inadvertently also answering the question "What's the easiest way to get guinea pigs ever?" At the end of the 30 days, the students had none of the liver or cholesterol troubles Spurlock reported. According to the guy in charge of the experiment (aka an actual scientist, not the guy who created MTV's I Bet You Will), the students' metabolism was able to adapt to the extra amount of food they were eating. They did feel more tired, but none of them experienced the mood swings and depression Spurlock claimed to have endured.

T.rex will be fine. He may make a mess of the drive thru if he doesn't get served now, though...

rhialto
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### Re: What-If # 0078 T-Rex Calories

Calories? I don't know why people are still using those. They were abolished at least 30 years ago. All food packaging must show Joules.

And then *food* calories? WTF?

I'd like to have the numbers in proper units please. Joules. (Not "food joules", just in case somebody feels the urge to invent such a horror).

Klear
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### Re: What-If # 0078 T-Rex Calories

I like the Dinosaur Comics reference in the mouseover text of the second picture.

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### Re: What-If 0078: "T-rex Calories"

mathmannix wrote:
Djehutynakht wrote:And also, if we were to replace our meat sources with dinosaurs (*old dinosaurs, not modern day aviary) which would be the most effective in terms of meat production

In short, which dinosaurs would make the best modern day cattle/pigs/chickens/etc?

True... presumably, large dinosaurs such as tyrannosaurs and sauropods would take a great amount of time and/or resources to reach full size. We're probably better off farming velociraptors for their meat, presuming that is ethical.

The best dinosaurs for farming would almost certainly be the herbivores, not the carnivores. As others have mentioned, you get a dramatic increase in required energy input if you start trying to farm carnivores - at some point you need to raise the herbivores to feed to the carnivores, and it's much more efficient just to eat the herbivores yourself. I'm going to assume mid-size herbivores would be best, but I don't know enough about dinosaurs to give any specific examples.

I guess this might not be true if dinosaur herbivores are all incredibly inefficient for some reason, and it works out better to farm current domestic animals such as cattle (or goats) and feed them to T-Rexs.

vltava
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### Re: What-If # 0078 T-Rex Calories

Is anyone else bugged by the fact that there are 106 burgers in the last illustration, not 80?

kevsgrove
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### Re: What-If # 0078 T-Rex Calories

vltava wrote:Is anyone else bugged by the fact that there are 106 burgers in the last illustration, not 80?

How do you figure 106? I count 8 piles of 9 (72), a pile of 5 (77), and 3 singles (80).

Edit: Ah but he's also eating one, making us both incorrect.

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### Re: What-If # 0078 T-Rex Calories

kevsgrove wrote:
vltava wrote:Is anyone else bugged by the fact that there are 106 burgers in the last illustration, not 80?

How do you figure 106? I count 8 piles of 9 (72), a pile of 5 (77), and 3 singles (80).

Edit: Ah but he's also eating one, making us both incorrect.

I see 8 piles of 12, a pile of 6, and 4 loose burgers (including the one he's eating), for 106 total. I spent a long time trying to work out how to see the large piles as only having 9 burgers in, but I can't do it.

speising
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### Re: What-If # 0078 T-Rex Calories

obviously, randall never saw an elephant IRL before. those things are huge, especially when a bull is charging in your direction!

Klear
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### Re: What-If # 0078 T-Rex Calories

speising wrote:obviously, randall never saw an elephant IRL before. those things are huge, especially when a bull is charging in your direction!

Unlike Randall, I knew that Elephants are much bigger than cars, but following that google search link, holy shit, I still underestimated the size.

I'm not sure that's normal, but in Prague zoo you can see elephants from an elevated position, thus robbing them of some presence.

NiteClerk
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### Re: What-If # 0078 T-Rex Calories

The shirt link worked for me at http://www.topatoco.com/merchant.mvc?Screen=PROD&Store_Code=TO&Product_Code=QW-PERSON&Category_Code=QW

I did notice that the shirt says ..."contains about 39 million sperm cells and/or 500 thousand egg cells..." I wonder about the "and".

Flumble
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### Re: What-If # 0078 T-Rex Calories

NiteClerk wrote:I did notice that the shirt says ..."contains about 39 million sperm cells and/or 500 thousand egg cells..." I wonder about the "and".

You know when a male and a female love eachother very much and they cuddle very intimately?
Well, an ejaculation contains anywhere from ten million to a few hundred million spermatozoa (source; note that figures from intercourse are higher than those in the link), so at least women can have both after sex.

Btw, that figure of 39 million sperm cells is way off.

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### Re: What-If # 0078 T-Rex Calories

Sperm facts wrote: So the whole process is somewhat like a marathon run in a maze filled with mucus followed by breaking into a fortress.
The thing about recursion problems is that they tend to contain other recursion problems.

gmalivuk
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### Re: What-If 0078: "T-rex Calories"

mathmannix wrote:We're probably better off farming velociraptors for their meat
It is never energy efficient to farm carnivores for their meat instead of herbivores, and in addition small warm-blooded animals have relatively higher metabolism than large ones in order to maintain body temperature.

speising wrote:obviously, randall never saw an elephant IRL before. those things are huge, especially when a bull is charging in your direction!
It's also possible he was thinking of the ones in Thailand, which are much smaller than the African variety and also likely more commonly photographed near cars, since they're still used as work animals in some places.
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Klear
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### Re: What-If 0078: "T-rex Calories"

gmalivuk wrote:
mathmannix wrote:We're probably better off farming velociraptors for their meat
It is never energy efficient to farm carnivores for their meat instead of herbivores, and in addition small warm-blooded animals have relatively higher metabolism than large ones in order to maintain body temperature.

True, but it might be more efficient from an economic pov. Who wouldn't want a raptor burger? Besides vegetarians?

kevsgrove
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### Re: What-If # 0078 T-Rex Calories

kevsgrove wrote:
vltava wrote:Is anyone else bugged by the fact that there are 106 burgers in the last illustration, not 80?

How do you figure 106? I count 8 piles of 9 (72), a pile of 5 (77), and 3 singles (80).

Edit: Ah but he's also eating one, making us both incorrect.

I see 8 piles of 12, a pile of 6, and 4 loose burgers (including the one he's eating), for 106 total. I spent a long time trying to work out how to see the large piles as only having 9 burgers in, but I can't do it.

I zoomed in and you are indeed correct, I was trying to count using the little image initially. Now I can't manage to see piles of 9 anymore either. Maybe he still has 26 burgers leftover from a previous friend?

Icalasari
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### Re: What-If # 0078 T-Rex Calories

That shirt has me wondering how long you can make a single human last while getting as close to 100% of your daily requirements as possible (obviously the answer would fuck you over carbs wise)

Sunrider
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### Re: What-If # 0078 T-Rex Calories

Sorry to say, but Randalls calculations are wrong. One burger contains around 600kcal, not 600cal.
See: wikipedia -> Whopper

Using Calories is not a good idea, cause everybody in the world confuses kcal with cal. Even the guy who made the infamous t-shirt made this mistake. The correct value for a 80kg human is for sure more than 110kcal, cause this is only 1/6 of a Whopper (see above).

mathmannix
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### Re: What-If 0078: "T-rex Calories"

Icalasari wrote:That shirt has me wondering how long you can make a single human last while getting as close to 100% of your daily requirements as possible (obviously the answer would fuck you over carbs wise)

It partially depends on what the human "gobbled 10 hours ago." If you are planning on eating a person, you might as well force-feed her a bunch of brussel sprouts and maybe some riboflavin supplements first.
I hear velociraptor tastes like chicken.

gmalivuk
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### Re: What-If # 0078 T-Rex Calories

Sunrider wrote:Sorry to say, but Randalls calculations are wrong. One burger contains around 600kcal, not 600cal.
See: wikipedia -> Whopper

Using Calories is not a good idea, cause everybody in the world confuses kcal with cal. Even the guy who made the infamous t-shirt made this mistake. The correct value for a 80kg human is for sure more than 110kcal, cause this is only 1/6 of a Whopper (see above).
Nope, the t-shirt is fine: food calories (kcal) are exactly what nutrition labels always report in the Calories section.

The only person who seems to be confusing the two units here is you.
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PowerPlate
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### Re: What-If # 0078 T-Rex Calories

So
we have two units: "calories" and "food calories", which are off by a factor 1000
an then you lable a coloumn with the label "calories" and put numbers in the unit "food calories" in there

I believe I can see, why there is some confusion about this and it's not the people using only calories or kilo calories causing it.
Or are you of a different opinion?

gmalivuk
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### Re: What-If # 0078 T-Rex Calories

Yes, because basically every person ever can make the logical leap from the Calories entry on a food label to the food calories unit. (Additionally note that the distinction is case-sensitive, with the capitalized "Calories" typically being used for the larger unit.)
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PowerPlate
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### Re: What-If # 0078 T-Rex Calories

Only if one has ever heard of food calories. In the other case it's the most reasonable assumption, that the label "Calories" mean well calories.
And could it be, or is this another American vs Europe case? Because here in Europe we simply write cal and kcal.

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### Re: What-If # 0078 T-Rex Calories

Food calories are the better known unit of the two here, by far. We usually learn it from people or television, but learn of calories in school.
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brenok
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### Re: What-If # 0078 T-Rex Calories

Hm, here in Brazil, despite everybody referring to them as simply "calories" in common speech, all food packages contain the energetic value in kilocalories and kilojoules:

Also, I've never heard the term "food calories" before.

gmalivuk
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### Re: What-If # 0078 T-Rex Calories

I don't think "food calorie" is really an official name, it's just an immediately clear way to describe the larger unit also commonly called a "calorie" that is used for food.

Incidentally, the kilogram calorie was first. It was later displaced by the gram calorie and the joule as standard, but the original sense is the one still used in the US on food labels.

Due to the confusion this apparently causes for our European readers, I move that US food labels be changed to the unambiguous BTU.
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### Re: What-If # 0078 T-Rex Calories

Looks up "unambiguous BTU". Wikipedia doesn't seem to have that one, but it does have seven others Though they do all have the decency to be within one percent of each other.
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### Re: What-If # 0078 T-Rex Calories

Well yeah, there's still the messy fact that water's specific heat capacity changes with temperature and pressure, but that's just as true for the calorie. So the BTU still has the advantage, because as far as I know there's no identically-named unit a full three orders of magnitude bigger or smaller.
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