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Dinosaurs versus mammals
I am new to this list and an engineer in engineering physics very much
interested in dinosaurs.
I buy all books that I can find here in Sweden and the US on the subject. There
has also been an extensive series called Jurassica on the Discovery channel
here which has caught my interest dealing with many aspects of dinosaur species,
research and expeditions with many of the most known scientists in the field.
Does anybody know if this series is available on video?
Now for my QUESTION: In all books and TV-programs there has not been a clear
analysis and answer to why mammals (and the protomammals before them)
were so profoundly outcompeted by the
dinosaurs for such a long time (or have I missed that?).
I think there must be very fundamental reason for this, maybe some of the
1. Biomechanical; that dinosaurs had an advantage in anatomy or power
that made them more durable, faster or just bigger. I recall an analysis
in a Jurassica program that the forefathers of the mammals (the protomammals)
in the Triassic era had only one opening on each side of the
skull compared to the dinosaurs' two that enabled the latters to have
stronger bite muscles or whatever.
I think I read in Bakker's "Heresies"about one theory that the dinosaurs
outcompeted the protomammals because of the upright leg anatomy, hence
2. Biochemical; that dinosaurs had a more efficient energy conversion system.
If the dinosaurs were cold blooded, which is still debated, combined with a
much warmer stable ideal climate, were they simply much more efficient
machines than mammals? Less food and maybe more power at the same time.
Does a cold blooded animal of the same body weight as a mammal have
better muscle performance in warm ambient temperature? From a systems
standpoint, I have understood that the temperature control mechanism in
mammals burns a lot of energy itself through the high metabolism.
With the falling temperatures at the end of the Cretaceous,
the regulated temperature of the mammals simply enabled them to live on
and not the dinosaurs?
Could the dinosaurs have been partially warm bloodied but with still most
of the cold bloodeds' energy efficiency? An intermediate metabolism form
that does not exist today?
All signs on warmbloodedness in dinosaurs seem to be difficult to explain
Pure warmbloodedness would have an unplausibly high food consumption.
3. Reproduction performance. I have no ideas about differences here! Different
reproduction principles can have a great effect on survivability in different
e.g. for marsupials in Australia which have the ability to wait to give birth
until food is
4. Disease immunity. I suppose it is very hard to know if the dinosaurs were
robust in this aspect. See Bakker's "Heresies" about warm bloodedness's
An interesting parallell may be that sharks apparently do not have cancer.
5. Genetics: could there be a difference in number of chromosomes or amount
of genetic information that made them more robust or adapt faster/better to
changes in environment?
The inherent superiority of the dinosaurs seems to have been so big that no big
intelligent brain was needed to outcompete the mammals! This raises
another thought: do most other life bearing planets in our galaxy simply have
stopped at this stage of stupidity in evolution because of more stable
temperature and geology than in the history of the earth preventing mass
extinctions, hence no signs of intelligent signals in the SETI program?
Intelligence is not required to successfully transfer your genes from
generation to generation for hundreds of millions of years....
Being just an amateur on this list, please tell me if this question is already
answered and if my thoughts are simply too unprofessional! This is my first
try to contribute something.
Soren Eriksson email@example.com
from Sweden, that has mostly only pre Triassic sediments, hence very
few dinosaur fossils!
P.S. Has Sue been sold yet? She would be one of the most impressive T-Rex
exhibited in the world!
"In theory there is no difference between theory and practice, but in practice
(stolen from some book)