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T. Rex Had a Body Temperature of 97°F

71 pointsby 5d agonytimes.com
122 comments
5d agoHN ↗

I read the headline in Celsius and thought that they were a bit too hot.

5d agoHN ↗

Would add a new fun dimension to Jurassic Park.

"Quick! Climb to 300 meters above sea level and the trex will boil and we will be safe!"

5d agoHN ↗

to make it even more egregious:

"Quick! Climb to about 1000 feet above sea level and the trex will boil and we will be safe!"

5d agoHN ↗

I know you were talking about a mountain or something, but "climb to <altitude>" does make one think about this exchange which would be in feet, not meters:

"climb to FL20 and the flying dinosaur thing will break" could work though

Since, annoyingly, international altitudes are done in increments of 1000 feet (ish, handwaving)

5d agoHN ↗

Up until the early 2000s, dinosaurs were thought to be rather reptilian and therefore probably coldblooded, Dr. Wiemann said. That began to change as multiple lines of evidence from geochemistry studies and CT scans of fossils showed they were warm-blooded. Dr. Wiemann had previously found that T. rex had a fast metabolism, but she said the new study did an “exquisite” job of zeroing in on a precise body temperature.

To take the body temperature of a long extinct, school-bus-size predator, scientists at the University of California, Los Angeles, used a clever geochemistry technique on fossilized teeth, including two from “Thomas,” a famous T. rex in the collection of the National History Museum of Los Angeles County.

fascinating

we've also learned more about the air at the time via teeth, https://nautil.us/the-data-in-a-dinos-smile-1229729

5d agoHN ↗

It intuitively makes sense. A cold-blooded creature of that mass would take a long time to properly warm up or cool down. Most modern cold-blooded animals are small, e.g. frogs, snakes, lizards. They can move into the sunlight or shade as needed and pretty quickly change temperature.

5d agoHN ↗

From the paper, that is: 36.3 ± 2.5°C.

5d agoHN ↗

Thanks, I thought it was almost boiling.

5d agoHN ↗

So 97.3 ± 4.5 °F for anyone else curious how the precision translates.

5d agoHN ↗

Phew! Thank you! I feel for the ungodly fahrenheit again

5d agoHN ↗

Better for day to day life, worse for science and engineering.

5d agoHN ↗

Is it really better for day to day life? I am certain that it only appears so because you're used to it. I think for day to day life they're both roughly equivalent.

Of course, for me Celsius is more natural and intuitive, but again - that's because I'm used to it.

5d agoHN ↗

100F is about peak summer heat; 0F is about peak winter chills. Works great for describing weather .. in various places.

4d agoHN ↗

I have slept in a tent in -31 F, what is this "peak winter chills" you claim to speak of?

5d agoHN ↗

You can basically put a "%" after a fahrenheit temperature and read it as "percentage of a really hot day" and you'll get a pretty good idea what it feels like outside.

It's pretty well calibrated as a 0-100 scale for human temperature perception.

5d agoHN ↗

I moved from a cold climate to a tropical climate and let me assure you there's no human universal understanding of what's comfortably hot or cold, definitely not to the point of putting a percentage on it. I can walk around in a T-shirt and shorts at 17C (62f) while locals will be wrapping up in scarves and talking about how freezing it is. Meanwhile they'll be fairly comfortable at 35C (95f), at least if the humidity isn't high, and I'll be stuck in with the AC blasting.

So in other words Fahrenheit is a western centric measurement (or at least, temperature climate centric), while Celsius is universal.

5d agoHN ↗

The subjective experience doesn’t really matter because many places in the US will experience a 100 degree F range over an entire year. So it’s not the “comfortable range” but the actual range you’ll get in many parts of the US (whether you like it or not).

5d agoHN ↗

You can do the same thing with celsius if you live in a country with a different temperature "calendar".

I'm used to the idea that 0C is what splits the year between cold season and warm season. Obviously people from California will see it differently, for example.

So where I live it is like this:

30 or more - hot

15..30 warm

0..15 chilly

-15..0 calendar winter

-30..-15 real winter

..-30 - freezing, kinds younger than 12 don't go to school

4d agoHN ↗

It doesn't map nearly as well for those of us who regularly have temperatures under -17C/0F in the winter. For me Celsius maps a LOT better to the temperatures I actually deal with year round. -17C is, accounting for wind chill, an average-ish winter day, that I'd consider pretty comfortable at this time of the year, assuminv appropriate clothing.

5d agoHN ↗

It's just how some Americans justify this particular measurement system.

As you said: it's what you're used to. I know 100F is a very warm day, but if someone said it was 50F I wouldn't intrinsically know how warm or cold that is. My brain works in Celsius, so someone saying its 20C I understand instantly.

Similarly length in US football fields - I don't know what that is, but it's second nature to someone who did grow up using them as a measurement.

5d agoHN ↗

Kelvin is superior for science and engineering but doesn't arbitrarily anchor the scale to the freezing and boiling point of water in the way Celsius and Fahrenheit both do.

273.15 Kelvin doesn't roll off the tongue like 0°C or 32°F.

5d agoHN ↗

Relatively speaking? Yes. Also, the layman rarely needs to know the boiling point of water. The freezing point is useful though.

For serious scientific and engineering applications the freezing and boiling point of water isn't actually 0°C and 100°C in most real scenarios.

5d agoHN ↗

It doesn't anchor the scale to water, but it still scales the scale to water since it's still exactly 100 degrees between its boiling point and freezing point.

3d agoHN ↗

At sea level (or more precisely, at an atmospheric pressure of 101325Pa).

5d agoHN ↗

counterpoint: it doesn't matter, since you need to learn relevant boiling/freezing temperatures on both scales anyway.

As a european: F is the only american system that is easy to use and reason with (considering its 0-100 range is spanning the "doable" temp range of too-cold to too-hot), unlike other imperial systems for lengths and whatnot.

5d agoHN ↗

I would argue feet and inches are pretty good too, since there’s a foot on your body, and a thumb, too, for inches.

Weight, mass and considerable distances, I’ll grant you, though.

4d agoHN ↗

let me show you the size difference between my wife's thumb and mine, and let's debate again.

4d agoHN ↗

I feel like you’re intentionally misrepresenting me. I’m obviously talking about number sense, mental visualization, etc.

5d agoHN ↗

I quite like Fahrenheit. The 0 to 100F (-17 to 37C) range perfectly encapsulates the range of outdoor temperatures I expect to encounter during the year. If the forecast is outside that range, it’s going to be miserable.

5d agoHN ↗

Same. I prefer Celsius for most other things but I find Fahrenheit very well suited to climate usage.

5d agoHN ↗

Wouldn't be surprised if the smaller raptors had even higher body temps.

5d agoHN ↗

Seems sensible, given that birds have higher body temperatures.

4d agoHN ↗

I wish raptors could be reanimated and made in miniature so you could have little Raptor domestici (house raptors) running around causing all kinds of hijinks

4d agoHN ↗

I think many of them were about the size of turkeys.

Velociraptor was quite small. Jurassic Park used Utahraptor, or Deinonychus as a model.

3d agoHN ↗

The cassowary is here and alive today, but you wouldn't want of them in your backyard!

5d agoHN ↗

i know its the nytimes, so we can assume american units, but i find it sort of crazy that even throughout the body of the article it doesnt ever say "fahrenheit".

5d agoHN ↗

It doesn't need to. Any other unit would be either insanely cold or insanely hot.

5d agoHN ↗

Given that it’s a shouty headline in a major publication, that’s what I would have expected.

5d agoHN ↗

Common sense suggests that living creatures are likely not boiling when they have a mild fever.

5d agoHN ↗

i am not a paleontologist and there have been many extremely weird living creatures over the time earth has been around.

and as the sibling comment mentions, i am primed for science articles to be metric.

5d agoHN ↗

I’m metric all the way, but if it would use metric, it still should unambiguously state: C

5d agoHN ↗

indeed! my "common sense" is to always state the units you're working with, no matter how obvious you think it is.

at least, that was the concept was drilled into me throughout all my schooling. perhaps that has changed in the last few decades.

5d agoHN ↗

Common sense would be using metric units in science-related article.

5d agoHN ↗

Americans don't use Celsius when talking about their body temperatures, and that's who the audience is.

5d agoHN ↗

Americans don't use Celsius for anything except scientists talking with other scientists.

5d agoHN ↗

that hasn't been my experience. Its widely used in engineering and has been for decades.

5d agoHN ↗

Ya, I think engineering falls under the umbrella of “scientists talking to other scientists”

5d agoHN ↗

A lot of monitoring software defaults to displaying hardware temperatures in Celsius regardless of the locale, and I've gotten so accustomed to knowing what a reasonable temperature is for different components that I personally never change the display units.

5d agoHN ↗

It's a US-based newspaper written for the general public. Common sense would say it's using US units.

5d agoHN ↗

This is what I told my chemistry teacher in high school when he marked me down for not including units, too.

5d agoHN ↗

Common sense also suggests using the SI units that ~95% of the planet uses, but here we are.

5d agoHN ↗

I know nothing about dinosaurs, so if you had told me that their blood was 97°C then I would've believed you

5d agoHN ↗

This is really interesting, worth a read. Wouldn’t be surprised if the even larger dinosaurs had even higher body temps!

5d agoHN ↗

How do we know its body temperature was 97 degrees, and simply not the environment was 97 degrees?

5d agoHN ↗

What environment would stay at a constant 97 degrees?

5d agoHN ↗

If it was environmental then you'd expect it to fluctuate over time, but they also checked it against an animal they knew to be cold blooded, if it was environmental you'd expect them to be the same, but that animal was calculated by the same method to be colder.

5d agoHN ↗

They compared against crocodilian teeth and those teeth were at a different temperature. Crocodilian teeth are known to be at a similar temperature to their environment because they are known to be cold blooded.

It is correct to say that we don't know they were warm blooded, just that their body temps were likely the given observed temperature.

3d agoHN ↗

i assume this means crocodiles from the same time period?

2d agoHN ↗

They measured it. Thanks to AI, we can measure things today which would not have been possible 2 millions years ago. /s

5d agoHN ↗

Farenheit. So a little bit cooler than us.

5d agoHN ↗

i will now believe this information until it becomes outdated in the future, at which point i will believe that information until it becomes outdated later

5d agoHN ↗

Great! That's how knowledge is supposed to work.

5d agoHN ↗

It's good to know you've learnt something!

5d agoHN ↗

'Hotter than a crocodile, cooler than a chickennnnn....'

is the opening line to a great song i'll never get to hear.

5d agoHN ↗

Claude Sonnet 5 on openrouter.ai/chat

Write a song about the T-rex. First line "Hotter than a crocodile, cooler than a chicken". Format for aisonggenerator.io.

Then I copied the output to aisonggenerator.io (1 free song per day), and used Audacity/Tenacity to record the MP3 because they make you pay to download.

5d agoHN ↗

id assumed as much since seeing jurassic park in 1996

5d agoHN ↗

I wonder if that's triggered if NYT determines that a gift link is being widely used?

5d agoHN ↗

Repost from a different thread: Related only topically, a 1hr YouTube talk I enjoyed a lot: "Hatchling T. rex and the Evolution of Vertebrate Parental Care" by Nick Longrich: https://www.youtube.com/watch?v=zd0dR2n9hLA

He's a paleontologist and the talk starts with some pretty interesting statistical analysis aiming to estimate T rex clutch sizes (66 eggs) and hatchling weights (1.5kg) as well as T rex parental care. It ends with looking at evolutionary history trends in increasing parental investment in radically different animals.

He talks a little slow, so a little playback speed bump won't go amiss.

5d agoHN ↗

Please add the measurement system to the title. The times should know better...

5d agoHN ↗

Though it should be pretty obvious from this context that it's not 97 Celsius or Kelvin.

5d agoHN ↗

Sure, but 'F' is a lot shorter than "whichever unit doesn't kill the dinosaur."

5d agoHN ↗

Weird, my browser somehow doesn’t render the title as “T. Rex Had a Body Temperature of 97 Degrees whichever unit doesn’t kill the dinosaur”. It just leaves that last part out, making it even shorter than “F”.

5d agoHN ↗

"T. rex was warm" is even shorter again. I think we’ve established that omitting information saves space.

5d agoHN ↗

My boyfriend and I were confused because I thought humans have a body temp higher than 97dF and somehow the title made me think this was exceedingly high.

5d agoHN ↗

Unless the Earth was a __VERY__ different place

5d agoHN ↗

The Times is a US magazine. The odds of them picking a US unit of measurement are very high.

5d agoHN ↗

This makes sense from a context and writer perspective.

Most conversation about climate change has been around global average temps raising in C. Further, switching that back and forth and doubling it for F would be seen as manipulative by people that don’t want to hear it.

On the contrary, the Times’s US audience (probably their main audience) thinks of body temp, which this is, in F.

To add further, the audience and writers that want to share cool, new dinosaur fact and the group that does an update on global warming are different people and operate and think differently around these specific things in these specific contexts.

Of course it would be easier to add the letter, but I can definitely see why it wasn’t included.

5d agoHN ↗

That’s a reasonable explanation for choosing Fahrenheit. It’s also a pretty good explanation for choosing to label it, since the same paper uses both scales.

5d agoHN ↗

Indeed.

It also turns out, as someone else in this thread has noted, NYT's style guides say to not include the unit in headlines, so here we are :)

5d agoHN ↗

I have asked ChatGPT to draw me an image of a 97 degree celsius t-rex and the result was absolutely amazing

5d agoHN ↗

It seems that this headline is following the guidelines of the times style guide: "In general, ordinary references to temperature do not specify the scale."

5d agoHN ↗

A random, spare letter wastes space and might have been A/B tested to have a higher click away rate.

5d agoHN ↗

Well it’s definitely not 97 K, it’s definitely not 97 C, so it’s probably 97 F which would put it in the same general ballpark as nearly all terrestrial vertebrates.

5d agoHN ↗

I can testify that my baseline body temperature (measured sublingually) is 97.6℉

By the way, Google Fit's body-temperature entry is cool, but when it comes to "Location", why is "mouth" in the middle of the list and next to some other, unrelated parts? How is the list being sorted?

5d agoHN ↗

the best part of this kind of science is that there’s no way to reproduce it or prove if it’s actually true, but it makes a great pop science article