Dinosaurs were warm - cuddlie not yet confirmed

[AstralTraveller (David)]

The first significant finding of the new 'clumped isotope' palaeothermometer has been published.

Dinosaur Body Temperatures Determined from Isotopic (13C-18O) Ordering in Fossil Biominerals Robert A. Eagle, et al. Science 333, 443 (2011); DOI: 10.1126/science.1206196

Abstract: The nature of the physiology and thermal regulation of the nonavian dinosaurs is the subject of debate. Previously, arguments have been made for both endothermic and ectothermic metabolisms on the basis of differing methodologies. We used clumped isotope thermometry to determine body temperatures from the fossilized teeth of large Jurassic sauropods. Our data indicate body temperatures of 36° to 38°C, which are similar to those of most modern mammals. This temperature range is 4° to 7°C lower than predicted by a model that showed scaling of dinosaur body temperature with mass, which could indicate that sauropods had mechanisms to prevent excessively high body temperatures being reached because of their gigantic size.

In my ignorance I assumed that if they were warm they were 'warm blooded' like us. Now it turns out that their body temperature was too low for them to be 'cold blooded', because big animals have a smaller surface area to mass ratio. In an interview one of the authors discussed possible future research methodologies which could help resolve the uncertainty (eg look at smaller related species, look at juveniles of the same species) and made a very convincing case for more research funding. Obviously the data set is quite small but that what you get from a new, technically difficult technique. Papers using the type of analysis I do have dozens to perhaps 100s and even 1000s of determinations but back in the 1950s 3 determinations was a paper. The technique will improve, commercial manufacturers will start to develop 'off the shelf' instruments and output will increase. Although in this work addressed a biological question the technique can also be applied to geological samples (eg corals, soil carbonates, possibly speleothems). It will be interesting to follow how our understanding of Earth history is enhanced and altered over the coming decade as more labs come on line around the world.

[GeoffW1 (Geoff)]

Hi,

Don't know about cuddly but I've often wondered, since we know birds are their modern descendants and are warm-blooded, just when that major change happened if all dinos were relatively cold-blooded.

I recall once watching a doco on flying dinosaurs and thought that the energy requirement there really implied a warmer faster metabolism.

A case of generalising too much?

Cheers

[supernova1965 (Warren)]

Yeah remind me to cuddle up to a T-REX next time I see one

[icytailmark (Mark)]

give a T Rex a big kiss!!!!

[Jen]

Aww i have an image in my head now of a big huge fluffy PURPLE dinosaur with long cute eyelashes how cute
I love dinosaurs

[Jen]

Originally Posted by supernova1965

Yeah remind me to cuddle up to a T-REX next time I see one

jen gets camera ready for that LOL

[astroron (Ron)]

Originally Posted by supernova1965

Yeah remind me to cuddle up to a T-REX next time I see one

Warren you are showing your age again
How did you survive the KT exstinction

[renormalised (Carl)]

Originally Posted by AstralTraveller

The first significant finding of the new 'clumped isotope' palaeothermometer has been published.

Dinosaur Body Temperatures Determined from Isotopic (13C-18O) Ordering in Fossil Biominerals Robert A. Eagle, et al. Science 333, 443 (2011); DOI: 10.1126/science.1206196

Abstract: The nature of the physiology and thermal regulation of the nonavian dinosaurs is the subject of debate. Previously, arguments have been made for both endothermic and ectothermic metabolisms on the basis of differing methodologies. We used clumped isotope thermometry to determine body temperatures from the fossilized teeth of large Jurassic sauropods. Our data indicate body temperatures of 36° to 38°C, which are similar to those of most modern mammals. This temperature range is 4° to 7°C lower than predicted by a model that showed scaling of dinosaur body temperature with mass, which could indicate that sauropods had mechanisms to prevent excessively high body temperatures being reached because of their gigantic size.

In my ignorance I assumed that if they were warm they were 'warm blooded' like us. Now it turns out that their body temperature was too low for them to be 'cold blooded', because big animals have a smaller surface area to mass ratio. In an interview one of the authors discussed possible future research methodologies which could help resolve the uncertainty (eg look at smaller related species, look at juveniles of the same species) and made a very convincing case for more research funding. Obviously the data set is quite small but that what you get from a new, technically difficult technique. Papers using the type of analysis I do have dozens to perhaps 100s and even 1000s of determinations but back in the 1950s 3 determinations was a paper. The technique will improve, commercial manufacturers will start to develop 'off the shelf' instruments and output will increase. Although in this work addressed a biological question the technique can also be applied to geological samples (eg corals, soil carbonates, possibly speleothems). It will be interesting to follow how our understanding of Earth history is enhanced and altered over the coming decade as more labs come on line around the world.

The were warm blooded, Dave. What that abstract is saying is that their body temps were 4-7 degrees C lower than they should be if you scaled temp by body mass. In other words, they were homeothermic...they could regulate their body temps no matter what environment they were in and keep them at an optimum. It's probably likely that like us, they could sweat to keep themselves cool when they got hot and shiver when they got cold. Mind you, the thought of a 100 ton Argentinosaurus shivering would be a strange sight to see. Might make for a good way to demolish buildings!!!!

[Ric]

I can just see a Brontosaurus keeping warm in it's IIS beanie and a really really long scarf.

[supernova1965 (Warren)]

Originally Posted by astroron

Warren you are showing your age again
How did you survive the KT exstinction

The T-REX I last cuddled swollowed me whole and when he died I managed to escape with my trusty knife. It is not my age I am showing but my secret time travel device is under threat from revelation OOPS I let the secret out I better stop using it till the heat settles down

[Jen]

now thats an imagination

[AstralTraveller (David)]

I've found a podcast of an interview with the lead author that runs for about 10 minutes. http://www.sciencemag.org/content/332/6037/1585.2.full
It covers the background of the warm/cold blooded debate and the significance of the new data.

Warren, sauropods were herbivores and so would only crush you by accident. If you could get up close you'd probably find the feathers quite soft, though not necessarily purple. They may have even been quite docile and stood there while you wrapped the 50m scarf around them and placed the size 372 IIS beanie on their bony noggin.

[renormalised (Carl)]

Originally Posted by AstralTraveller

I've found a podcast of an interview with the lead author that runs for about 10 minutes. http://www.sciencemag.org/content/332/6037/1585.2.full
It covers the background of the warm/cold blooded debate and the significance of the new data.

Warren, sauropods were herbivores and so would only crush you by accident. If you could get up close you'd probably find the feathers quite soft, though not necessarily purple. They may have even been quite docile and stood there while you wrapped the 50m scarf around them and placed the size 372 IIS beanie on their bony noggin.

Whilst dangling several storeys off the ground

[Ric]

Hey Jen, you could always knit them a purple cardigan.

[Waxing_Gibbous (Peter)]

Hmmmnnn...?
I can just see them at 'Crufts'.
"And this year's "Supreme Champion, despite failing the obediance round, - Grand Chanmpion Attila bis Barbarossa or 'Snoogles', the Alosaurus from Henley, who easily 'dispatched' his competition."

[Jen]

Originally Posted by Ric

Hey Jen, you could always knit them a purple cardigan.

lol and a beannie

[AstralTraveller (David)]

Originally Posted by Ric

Hey Jen, you could always knit them a purple cardigan.

Tsk tsk. Purple isn't a colour for cardigans. Purple is for hot pants. "Does my tail look gigantic in this."

[Jen]

Originally Posted by AstralTraveller

Tsk tsk. Purple isn't a colour for cardigans. Purple is for hot pants. "Does my tail look gigantic in this."