[Scarlet King Snake (OP)]

Is there any evidence of dinosaurs possibly being warm blooded or even being mammals?

[gsmollin]

Dinosaur morphology was wrong to have been mammals. To my knowledge, no one thinks dinosaurs were mammals. The warm-blooded question remains a topic of debate, however. All the evidence is circumstantial. Birds are warm-blooded, and reptiles are cold-blooded. Dinosaurs resembled both, and seemed to act like both. Maybe the answer is somewhere in the middle, with some being cold, and some having some temperature control. Also, dinosaurs ruled the animal kingdom for ~100 million years, and evolved considerably during that time, so cold or warm may have changed both by species, and timewise.

[Scarlet King Snake (OP)]

Actually I brought this up because there is still a large debate as to whether they'e warm or cold blooded.

Science is everywhere.

[qpan]

Its hard to imagine warm blooded reptiles - but maybe some/all dinosaurs were and thats why they became extinct (would probably be highly specialised and successful in their respective environments, but useless when environment changes).

"I have great faith in fools; self-confidence my friends call it."
-Edgar Allan Poe

[Scarlet King Snake (OP)]

Its quite possible due to information received from the preserved heart of a Thescelosaurus since it resembles more of a mammals heart or a birds not a reptile.

Science is everywhere.

[qpan]

In what way was it preserved? Would have had to survive at least 65 million years! Thats one hellava preservative!

"I have great faith in fools; self-confidence my friends call it."
-Edgar Allan Poe

[Scarlet King Snake (OP)]

It was actually fossilized heres the site.
newbielink:http://www.enchantedlearning.com/subjects/dinosaurs/news/Heart.shtml [nonactive]

Science is everywhere.

[qpan]

Cool-but how exactly does tissue become fossilised (as usually its the bones)? I suppose in rare cases (such as if the dinosaur falls into a bog) and the tissue is preserved, then the tissue might last long enough to be fossilised, but it must be some strange method of fossilisation to be able to preserve the structure of the tissue (especially the internal detail too).

"I have great faith in fools; self-confidence my friends call it."
-Edgar Allan Poe

[tweener]

This is very interesting.  There's more information and images here:
http://www.dinoheart.org/insideout/index.html

I don't know what I'm looking for, but some of those images seem a real stretch to me.  Very interesting though.

----
John - The Eternal Pessimist.

[chris]

Dinosaurs are close relatives of birds and reptiles. The closest living reptile ancestor is the crocodile. But significantly, whilst birds have a 4 chambered heart like our own, reptiles have a 3 chambered heart (2 atria with a single ventricle), and crocodiles have a 4 chambered heart (like ours) but with an extra-pulmonary branch (the so-called right systemic artery) which allows blood to bypass the lungs under low-oxygen conditions.

Where dinosaurs fit into this jigsaw is a matter of considerable debate. I spoke with a palaeontologist about this today who told me that the fossilised heart discovered recently is now not believed to demonstrate a 4 chambered architecture as claimed previously. Instead the identified morphology is thought to be artefactual. The jury is therefore still out.

Similarly, we still do not know whether dinosaurs were hot of cold blooded. It is likely that many of the large meat-eaters were warm-blooded; indeed when they emerged from the egg many dinosaurs like Tyrannosaurus were probably feathered to preserve heat. However, as they grew, the need for heat conservation became less of a problem and in fact heat-loss became more of a priority. So-called 'gigantothermy' takes over whereby an animal is so big that it literally cannot lose heat fast enough. This is thought to have driven the development of heat-loss mechanisms like long necks and skin plates doubling as heat-sinks. The evidence that this is the case comes from modern-day big crocodiles. Large specimens maintain an even body temperature continuously, despite (in theory) being cold blooded.

Chris

"I never forget a face, but in your case I'll make an exception"
 - Groucho Marx

[Scarlet King Snake (OP)]

Very helpful thank you Chris.

Science is everywhere.

[Broca]

A fossil of a T-Rex was found in S. Dakota.(named Samson) It is touted as the most complete T-Rex skeleton ever found. The article I read also talks about the fact that the orbits are found further back on the side of the head lending us to believe that it was NOT the horrid meat eating preditor that we have long thought. I don't think this article convinced me that the T-Rex was a warm fuzzy kind of guy, but it was interesting.

http://www.carnegiemuseums.org/cmnh/exhibits/carnegiesdinosaurs/paleolab.htm

[Exodus]

quote:Originally posted by Broca

A fossil of a T-Rex was found in S. Dakota.(named Samson) It is touted as the most complete T-Rex skeleton ever found. The article I read also talks about the fact that the orbits are found further back on the side of the head lending us to believe that it was NOT the horrid meat eating preditor that we have long thought. I don't think this article convinced me that the T-Rex was a warm fuzzy kind of guy, but it was interesting.

http://www.carnegiemuseums.org/cmnh/exhibits/carnegiesdinosaurs/paleolab.htm

hmmm, nah. You don't evolve an animal with such powerful jaws and teeth for it to ***** foot around and scavenge. Most scavengers are fairly small, just think how much T Rex would have to scavenge to stay alive? intersting all the same.

[sonofjackass]

ok, you know, i used to believe that T.rex was a powerful predator, but you know, actually jack horner's evidence is pretty good, if you dont know about it, i'm gonna try to explain it
1. the t.rex femur is shorter than the tibia and perone, so, this makes it slow. this is why ostriches are faster than humans, even when human legs are almost as long as the ones in ostriches. this made t.rex a slow runner, in fact, its possible than t.rex couldnt even run, instead, the fastest locomotion for a t.rex would be something like a fast walk.
2. not all the scarvangers are small... and in fact, they have to be big and more powerfull than predators. here in mexico, when a hawk kills its prey, it has to eat fast, because the bigger and stronger vulture is always there. the vulture is stronger, and bigger cause it has to scare the hawk, not because it has to kill the pray. this also happens with the hyena, which is bigger than the cheetah only because it has to scare the cheetah to succesfully scarvange.
3. guess who has the most powerfull jaws in africa today? a scavanger, the hyena. the scarvangers have to have a powerfull bite, to be able to esat the left overs, such as bones.
i hope this was useful, and excuse my english... by the way, dinosaurs were warm blooded

to cry is to know that you're alive

[Raedon]

I wonder if they tasted like Chicken or Turkey [8D]


It is good to be alive! It's impossible I'm here but here I am.. and I rock!

[johanna]

Are t rexes warm blooded? Did they amniotic eggs? Did they sing to their young? Please help me answer theses questions, it's for school!

johanna

[ADD HAHAHA]

scientists think mammals came from a dog sive dino looking thing. it produced milk, layed eggs, partnared 4 life, protective parents, and had hair!!!

http://www.abc.net.au/dinosaurs/tv_series/default.htm this should help

scientist think t rex had amniotic eggs, communitated(sang) to their young and were a mix between cold n warm blooded.

i think trex ran down its pray, suprised its pray, and hurased its pray. i also think dinos r MORE related to birds then reptiles(atleast the carnivourse) the way their hips n backs r structsured they r similer to an ostrige also the way they balance is like a bird.

[daveshorts]

If this is the same walking with dinosaurs that came out on the BBC a few years ago, you may well want to take it with a pinch of salt. It was dreadful for mixing good science with stuff that is just wild speculation, it is possible there is evidence for amniotic eggs, the cold vs warm blooded thing is still a bit contraversial, but noone has any way of finding out whether they sang to their young or not!

Saying scientists think something is rather weak as all you need is one scientist to speculate slightly wildly, and an unscrupulous TV producer to run with it, and you suddenly find that scientists thing that black is white and up is down.

[ADD HAHAHA]

wat ever!

i think dinos had niether warm or cold but possible a mix it needs to warm up but it can also control the temputer and pressure.

Drew Rody

[Andrew K Fletcher]

Actually I posted it first

For many years dinosaurs were thought to be cold blooded. The general concensus now is that they were in fact warm blooded. There was after all a 50% chance of getting it either right or wrong :)Still even the brightest light will cast a shadow and a stopped clock can be correct twice a day.

But this adds some serious considerations with relatively un-elevated reptiles today. Is there a connection between the heat generated in warm blooded creatures and their more upright posture than the relatively un-elevated reptiles today? For example, does a giant monitor lizard generate more heat than say a gator or a crock?

Andrew


Actually I brought this up because there is still a large debate as to whether they'e warm or cold blooded.

Science is everywhere.