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T. Rex Had a Body Temperature of 97 Degrees

35 pointsby 3h agonytimes.com
48 comments
2h agoHN ↗

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

1h 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!"

2h 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

1h 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.

2h agoHN ↗

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

2h agoHN ↗

Thanks, I thought it was almost boiling.

2h agoHN ↗

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

2h agoHN ↗

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

1h agoHN ↗

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

1h 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.

1h agoHN ↗

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

27m 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.

1h 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.

2h agoHN ↗

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

2h agoHN ↗

Seems sensible, given that birds have higher body temperatures.

2h 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".

2h agoHN ↗

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

2h agoHN ↗

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

2h agoHN ↗

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

2h 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.

1h agoHN ↗

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

1h 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.

2h agoHN ↗

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

1h agoHN ↗

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

1h agoHN ↗

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

1h agoHN ↗

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

2h agoHN ↗

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

2h agoHN ↗

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

2h agoHN ↗

What environment would stay at a constant 97 degrees?

2h 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.

2h 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.

2h agoHN ↗

Farenheit. So a little bit cooler than us.

2h 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

2h agoHN ↗

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

1h agoHN ↗

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

you know, like religion.

2h agoHN ↗

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

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

2h agoHN ↗

id assumed as much since seeing jurassic park in 1996

1h 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.