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T. Rex Had a Body Temperature of 97 Degrees

33 pointsby 2h agonytimes.com
45 comments
44m agoHN ↗

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

43m 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

19m 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.

40m agoHN ↗

Thanks, I thought it was almost boiling.

36m agoHN ↗

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

28m agoHN ↗

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

21m agoHN ↗

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

18m 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.

15m agoHN ↗

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

19m 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.

39m agoHN ↗

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

33m agoHN ↗

Seems sensible, given that birds have higher body temperatures.

38m 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".

36m agoHN ↗

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

28m agoHN ↗

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

35m agoHN ↗

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

32m 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.

22m agoHN ↗

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

20m 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.

28m agoHN ↗

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

23m agoHN ↗

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

22m agoHN ↗

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

37m agoHN ↗

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

36m agoHN ↗

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

33m agoHN ↗

What environment would stay at a constant 97 degrees?

32m 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.

24m 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.

36m agoHN ↗

Farenheit. So a little bit cooler than us.

34m 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

25m agoHN ↗

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

16m agoHN ↗

that's not knowledge - that's just theory and belief.

you know, like religion.

28m agoHN ↗

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

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

4m agoHN ↗

You included the line, but not as the opening line.

28m agoHN ↗

id assumed as much since seeing jurassic park in 1996

22m 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.