Were dinosaurs warm or cold-blooded ?

[UM-Bot]

A new study has suggested that the prehistoric reptiles were more likely to be warm-blooded like mammals.

The question over whether the dinosaurs were cold-blooded like today's reptiles and fish or warm-blooded like mammals and birds has remained a topic of controversy and debate for years.

Read More: http://www.unexplain...or-cold-blooded

[+DieChecker]

I vote Warm Blooded....

Wasn't there a study done that showed that dinosaur bones had channels in them for the blood vessels that were much more like mammals then reptiles? I've believed this for a long time.

Edited June 2, 2015 by DieChecker

[BeastieRunner]

I'm more found of the warm blooded aspects but can't it be both? A lizard-like line and a bird-like line?

[pokingjoker]

I'd think based on their size they would be warm blooded. Being cold blooded they'd require less energy, but due to size of animals their diets must have been huge, thus needing to be eating alot would require way more energy. Not to mention mating, frolicking, etc...

[Leonardo]

I'd think based on their size they would be warm blooded.

Their size might actually be an indication against them being warm-blooded. Homeotherms have to regulate their internal body temperature within a narrow range, and increasing size makes this increasingly difficult to achieve. Climate plays a part in this, as does the habitat of the organism - for example, whales are able to grow so large not only because of the bouyancy afforded by living in water, but also because water has a greater thermal capacity than air (i.e. it draws more heat from 'hot bodies' within it.)

There is some doubt that the larger, warm-blooded, terrestrial dinosaurs, huge sauropods for example, would have been able to maintain a constant body temperature because they could not dissipate heat fast enough to prevent overheating due to a much lower surface area/body mass ratio. Factor in the climate was generally warmer than present day Earth and very large warm-blooded animals would have an even tougher time surviving.

Edited June 2, 2015 by Leonardo

[Mr.United_Nations]

Ummm

http://www.bbc.co.uk/news/science-environment-27794723

in that it says dinosaurs were neither cold or warm blooded

[+Hammerclaw]

Since the largest land mammal weighed upward to twenty tons, dinosaurs at maturity in that size range and below could have been warm blooded. Theropods, the relatives of warm blooded birds most certainly were, The largest land mammal ever was Paraceratherium or Indricotherium.The largest known species (Paraceratherium orgosensis) is believed to have stood up to 5.5 m (18 ft) tall, measured over 9 m (30 ft) long and may have weighed up to 20 tonnes.

Edited June 2, 2015 by Hammerclaw

[XenoFish]

I'd say warm blooded. When I was a kid, I thought a triceratops looked a lot like a rhino. Still do.

Edited June 2, 2015 by XenoFish

[Leonardo]

Since the largest land mammal weighed upward to twenty tons, dinosaurs at maturity in that size range and below could have been warm blooded.

Yes, indeed. There is some doubt, however, that the largest dinosaurs were - could be - warm-blooded. So, the generalised claim that "dinosaurs were warm-blooded" quite well may be false.

I don't know of any other clade of organisms in which such a basic trait has diverged among different species, however. So this might suggest we need to rethink our categorisation of all those extinct species into just one clade of Dinosauria.

[+Hammerclaw]

Yes, indeed. There is some doubt, however, that the largest dinosaurs were - could be - warm-blooded. So, the generalised claim that "dinosaurs were warm-blooded" quite well may be false.

I don't know of any other clade of organisms in which such a basic trait has diverged among different species, however. So this might suggest we need to rethink our categorisation of all those extinct species into just one clade of Dinosauria.

This is an interesting link. Dinosaurs tend to bring out the child in me as they still are so uber cool! http://www.dinosaurhome.com/sauropods-ectothermic-or-endothermic-259.html Edited June 2, 2015 by Hammerclaw

[Infernal Gnu]

Me, too. I would LOVE to have a pet baby triceratops just as long as it didn't spear me in the thigh with its horn.

Thing I DON'T LIKE is the strong possibility that many dinosaurs might have had feathers.

[Myles]

I think warm blooded is the safe bet. Although I agree that some could have been cold blooded.

[Frank Merton]

I thought this was long-ago settled, at least for the later ones. I'm in my seventies and this is what I was taught in high school.

A more interesting question is whether or not dinosaurs were sentient. By "sentient" I mean experiencing the world through sensory qualia and emotional responses rather than reflexively the way a fish or an insect responds. It would seem that the brain pathways we associate with sentience first appeared in a group called the "mammal-like reptiles" that preceded both mammals and dinosaurs but not other reptiles.

[Zalmoxis]

Warm blooded, as they were not cold blooded like crocodiles or other reptiles.

[MissJatti]

Depends.. was the dinosaurs, reptiles, birds, or mammals???

also depends on flying dinosaur, swimmers, or land animals??

Edited June 4, 2015 by MissJatti

[newbloodmoon]

I had always been interested in this debate since Robert Bakker wrote the book Dinosaur Herasies. I think that it is a strong possibility for Theropods to be warm blooded as they needed to be more active with hunting. That's just a personal belief as I am not a paleontologist, if they ever find definitive proof one way or the other it will be exciting.

[OgreLord]

If they are warm blooded wouldn't we need to drop the ''saur'' from thier names? Warm blooded means they are not lizzards. I know it's a crazy question but it is bugging me and I would love for an expert to fix this madness, and solve this name problem. Dinobird? Dinobovine? UUUGH!

[TheGreatBeliever]

Obviously warm. If im not wrong there was no ice during the dinos time..

[adke]

This videos pretty good.

[ShadowSot]

There was a paper recently that argued that marine reptiles were warm blooded due to the isotopes in their teeth. Don't remember it at the moment.

The huge sauropods were supposedly to be warm blooded, the theory is that they were instead gigantothermic.

Being warm blooded is one of the size limiters for mammals. The bigger you are, the more surface area you need to bleed off heat.

Smaller dinosaurs were probably warmblooded, certainly theropods like velocirapter or Tyrannosaurus.

[+DieChecker]

I'd imagine that a sauropod would be one shape that would increase the surface area at the same time increasing size. Many of the largest ones were almost snake shaped in their neck and tail length.

[Taun]

"Were dinosaurs warm or cold-blooded?"...

Yes...

[SHaYap]

Maybe they;re more alike the Great White or Mako ~ endotherms

~

Most sharks are cold-blooded. Some, like the Mako and the Great white shark, are partially warm-blooded (they are endotherms). These sharks can raise their temperature about the temperature of the water; they need to have occasional short bursts of speed in hunting.

• link
  

~

Or meet Opah :

Meet the Comical Opah, the Only Truly Warm-Blooded Fish

Posted Thu, 05/14/2015

• nat geo link
  

~

[SlippySlug]

The original article is a year old, but I thought it was pretty much accepted long ago that dinosaurs were warm-blooded, at least the therapods. I might be remembering things completely wrong because it was about ten years ago, but didn't paleontologist Mary Schweitzer basically prove that T-Rex was warm-blooded by studying blood vessels in from its fossilized thigh bone? If that name sounds familiar, she was all over the news for discovering "soft tissue" in about a 65 million year old fossil.

You'd still have to wonder about the sauropods and whatnot. This...

I don't know of any other clade of organisms in which such a basic trait has diverged among different species, however. So this might suggest we need to rethink our categorisation of all those extinct species into just one clade of Dinosauria.

I can't wait for the day that starts to happen. It needs to be done.

[ShadowSot]

I'd imagine that a sauropod would be one shape that would increase the surface area at the same time increasing size. Many of the largest ones were almost snake shaped in their neck and tail length.

It's surface area to internal volume. If you're warm blooded you need a certain ratio of skin to internal meats to disperse excess body heat.

Sauropods were probably to large to do that successfully.