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.
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.
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.
> 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.
I didn't know this so I looked up the number for farm chickens, according to University of Kentucky (seems appropriate) they have a body temperature of "between 105°F and 107°F (40.6° and 41.7°C) ... Smaller chicken breeds have a higher body temperature than larger breeds"
> 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.
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.
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.
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.
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.
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.
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.
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).
Right, but "room temperature" is pretty universal everywhere because we are going with the "average human" rather than "outliers exist and maybe feel differently"
No it's not. Room temperature in tropical countries is often 26-30C.
I work in the food industry and this whole "room temperature" thing is a major bugbear for me actually because when so much food dates markings are designed around a room temperature of ~22C, it's a big health and safety issue for people (and shops, warehouses, restaurants) who don't know that and happily store the goods up to the date marking at 30C. Deciding that room temperature ~=22C and basing worldwide food safety on that is absolutely Western centric.
Obviously people here are not stupid and don't store meat etc. past when it's gone bad. But I've often bought e.g. oils from suppliers and it's clear that it's on the edge of rancidity even though it's got a year+ to go on the date because it's been stored at "room temperature".
The US has the widest range of temperatures of any country. Locations can vary by >50°C in a 24 hour period. Extreme temperatures are familiar to Americans and their society is well-adapted to it.
Calling Fahrenheit "western centric" is nonsensical. Every other country has a narrower temperature range that fits within the US temperature range.
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
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.
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.
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.
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.
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”.
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."
The same newspaper uses Celsius in its climate reporting, including the article below. Apparently the units depend on which extinction we’re discussing. One extra letter would save the guesswork.
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.
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.
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)
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".
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.
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
The word for what you're thinking of is "faith". Theory and belief are the constituents of all consciousness.
Young engineers sometimes fall into this trap - that there is absolute truth, and everything else. It would be nice if true, but it's wildly out of line with reality.
"Believing" something is not the same as having a dogmatic faith in something. We (ideally) change our beliefs with every new piece of input. That's good.
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?
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.
How do we know its body temperature was 97 degrees, and simply not the environment was 97 degrees?
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.
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.
What environment would stay at a constant 97 degrees?
Europe this summer? /jk
we don’t, all of this dinosaur stuff is bullshit
'Hotter than a crocodile, cooler than a chickennnnn....'
is the opening line to a great song i'll never get to hear.
Not yet a woman
The slop generator's gotchu: https://suno.com/s/gT2YhaQyNdlkzgeU
scans roughly to "macarena" if that helps (:
With the power of AI slop, you can hear anything: https://pmarks.net/posted_links/trex_ai.mp3
waiting for the video by neural derp like this one: https://youtu.be/lS6dtRWXF1o
Can you share the prompt?
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.
Wouldn't be surprised if the smaller raptors had even higher body temps.
Seems sensible, given that birds have higher body temperatures.
I didn't know this so I looked up the number for farm chickens, according to University of Kentucky (seems appropriate) they have a body temperature of "between 105°F and 107°F (40.6° and 41.7°C) ... Smaller chicken breeds have a higher body temperature than larger breeds"
https://afs.mgcafe.uky.edu/poultry/chapter-7-air-temperature
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
I’m missing Marc Bolan.
is it you, metal guru?
This is really interesting, worth a read. Wouldn’t be surprised if the even larger dinosaurs had even higher body temps!
> 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
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.
id assumed as much since seeing jurassic park in 1996
It's actually older, from 1993.
It's in the book. So 1990.
Internet says the inspiration for Alan Grant is Robert Bakker, and his first writings on it were in 1968:
https://en.wikipedia.org/wiki/Robert_T._Bakker
From the paper, that is: 36.3 ± 2.5°C.
Phew! Thank you! I feel for the ungodly fahrenheit again
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.
Same. I prefer Celsius for most other things but I find Fahrenheit very well suited to climate usage.
Fahrenheit is the superior measure
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.
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.
Better for day to day life, worse for science and engineering.
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.
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.
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.
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).
Right, but "room temperature" is pretty universal everywhere because we are going with the "average human" rather than "outliers exist and maybe feel differently"
No it's not. Room temperature in tropical countries is often 26-30C.
I work in the food industry and this whole "room temperature" thing is a major bugbear for me actually because when so much food dates markings are designed around a room temperature of ~22C, it's a big health and safety issue for people (and shops, warehouses, restaurants) who don't know that and happily store the goods up to the date marking at 30C. Deciding that room temperature ~=22C and basing worldwide food safety on that is absolutely Western centric.
Obviously people here are not stupid and don't store meat etc. past when it's gone bad. But I've often bought e.g. oils from suppliers and it's clear that it's on the edge of rancidity even though it's got a year+ to go on the date because it's been stored at "room temperature".
The US has the widest range of temperatures of any country. Locations can vary by >50°C in a 24 hour period. Extreme temperatures are familiar to Americans and their society is well-adapted to it.
Calling Fahrenheit "western centric" is nonsensical. Every other country has a narrower temperature range that fits within the US temperature range.
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
Sure, but we usually don't judge things on a scale from -30 to +30.
Judging anything on a scale from 0-10 (or 0-100) is very common.
Yes, but that the whole problem: this scale kind of suggests that you don't go below 0.
But this is not the case here, right?
Some people are used to higher temperatures and never seen snow while some people can't even imagine what it's like to have 40C (104F) outside.
0C is a great "common denominator" (irony). We all understand that generally this is when water changes its state and most people know how it feels.
And then your imagination can easily go lower or higher.
>Judging anything on a scale from 0-10 (or 0-100) is very common.
Now consider that many people live in places where 0F is warmer than what you actually have for a good part of a year.
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.
100F is about peak summer heat; 0F is about peak winter chills. Works great for describing weather .. in various places.
Arizona says "hold my boiling beer".
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.
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.
32°F and 212°F roll off the tongue?
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.
Doesn’t almost everybody cook? With boiling water?
>Better for day to day life
It is not.
really is, and I grew up in celsius.
Thanks, I thought it was almost boiling.
So 97.3 ± 4.5 °F for anyone else curious how the precision translates.
Please add the measurement system to the title. The times should know better...
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.
You're right but: https://news.ycombinator.com/item?id=49746671
Though it should be pretty obvious from this context that it's not 97 Celsius or Kelvin.
Sure, but 'F' is a lot shorter than "whichever unit doesn't kill the dinosaur."
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”.
"T. rex was warm" is even shorter again. I think we’ve established that omitting information saves space.
Unless the Earth was a __VERY__ different place
I have asked ChatGPT to draw me an image of a 97 degree celsius t-rex and the result was absolutely amazing
Don't hold out on us now...
https://cdn.shopify.com/s/files/1/0533/7369/8218/articles/16...
haha! OK good one.
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."
Wow is that actually their guideline?
A random, spare letter wastes space and might have been A/B tested to have a higher click away rate.
The Times is a US magazine. The odds of them picking a US unit of measurement are very high.
The same newspaper uses Celsius in its climate reporting, including the article below. Apparently the units depend on which extinction we’re discussing. One extra letter would save the guesswork.
https://www.nytimes.com/2026/09/02/climate/united-nations-cl...
Edit: Removed the headline quotation because the search listing and article heading differ.
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.
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.
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 :)
I read the headline in Celsius and thought that they were a bit too hot.
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!"
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!"
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)
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".
Common sense suggests that living creatures are likely not boiling when they have a mild fever.
I know nothing about dinosaurs, so if you had told me that their blood was 97°C then I would've believed you
Common sense also suggests using the SI units that ~95% of the planet uses, but here we are.
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.
I’m metric all the way, but if it would use metric, it still should unambiguously state: C
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.
This is what I told my chemistry teacher in high school when he marked me down for not including units, too.
Common sense would be using metric units in science-related article.
Americans don't use Celsius when talking about their body temperatures, and that's who the audience is.
Americans don't use Celsius for anything except scientists talking with other scientists.
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.
that hasn't been my experience. Its widely used in engineering and has been for decades.
Ya, I think engineering falls under the umbrella of “scientists talking to other scientists”
It's a US-based newspaper written for the general public. Common sense would say it's using US units.
It doesn't need to. Any other unit would be either insanely cold or insanely hot.
Given that it’s a shouty headline in a major publication, that’s what I would have expected.
https://archive.is/20260916181240/https://www.nytimes.com/20...
(Even the NY Times gift link requires a login.)
I wonder if that's triggered if NYT determines that a gift link is being widely used?
Farenheit. So a little bit cooler than us.
Wow! Close to boiling! /s
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
Great! That's how knowledge is supposed to work.
that's not knowledge - that's just theory and belief.
you know, like religion.
The word for what you're thinking of is "faith". Theory and belief are the constituents of all consciousness.
Young engineers sometimes fall into this trap - that there is absolute truth, and everything else. It would be nice if true, but it's wildly out of line with reality.
"Believing" something is not the same as having a dogmatic faith in something. We (ideally) change our beliefs with every new piece of input. That's good.
No, religion requires faith. Faith is belief without or in direct contradiction of evidence.
It's good to know you've learnt something!
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?