Subject:
|
Re: Evidence of Warm Blooded Dinosaurs
|
Newsgroups:
|
lugnet.off-topic.fun
|
Date:
|
Tue, 25 Apr 2000 03:41:59 GMT
|
Viewed:
|
302 times
|
| |
|
|
In lugnet.off-topic.fun, Bruce Schlickbernd writes:
> In lugnet.off-topic.fun, Lindsay Frederick Braun writes:
> > Jeff Stembel wrote:
> >
> > > Anyone interested in Dinosaurs should check this out:
> > > <http://www.washingtonpost.com/wp-dyn/articles/A53547-2000Apr20.html>
> > > Pretty cool, huh? :)
> >
> > I saw that! It sort of confirms what palaeontologists have thought since
> > about 1980. The fact that it's a plant-eater is more interesting,
> > though--the suggestion existed that "only predators needed that level of
> > energy." Hm.
>
>
> A similiar article appeared in the L.A. Times. One would suspect that
> warm-bloodedness goes back at least till the dinosaur-mammal split given the
> plant-eater angle.
This prompted me to pull out one of my dinosaur books, and examine the dinosaur
family tree. :) Anyway, if this chart is correct (it's ten years old, but I
doubt its changed much), then I'd guess Dinosaurs and mammals both evolved
warm-bloodedness separetly. My reasoning is this: Both Dinosaurs and
Crocodilians evolved from Archosaurs (Diapsids), whereas mammals evolved from a
separate branch (Synapsids). According to this chart, it appears the earliest
point at which dinosaur ancestors could've evolved warm bloodedness is the
branch of thecodonts that Dinosaurs evolved from (obvious, huh?), as opposed
to the branch Crocodilians evolved from. However, since present day crocodiles
and alligators have four chambered hearts, this probably evolved before the
reptile-mammal split. One also has to remember that the herbivorus dinosaurs
evolved *from* the carnivorus dinosaurs...
I'd like to hear other's opinions on this, especially if you have evidence to
contradict or confirm my idea (since I just made it up :) ). I'll also try to
find some of my more recent books on the subject. :)
Jeff
|
|
Message has 1 Reply:
 | | Re: Evidence of Warm Blooded Dinosaurs
|
| (...) Darn sacci-frasso-rassin' kids, stealin' my thunder...;) But yeah, that's the story. Why do crocodiles not have a high, warm-blooded metabolism? They don't need it, and have never needed it. They're archosaurs like monotremes are (...) (24 years ago, 25-Apr-00, to lugnet.off-topic.fun)
|
Message is in Reply To:
22 Messages in This Thread:
  
 
- Entire Thread on One Page:
- Nested:
All | Brief | Compact | Dots
Linear:
All | Brief | Compact
This Message and its Replies on One Page:
- Nested:
All | Brief | Compact | Dots
Linear:
All | Brief | Compact
|
|
|
|
