[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

Re: Airbagged(was Dive!Dive!Dive!)



        As Holtz has noted, the "short metatarsals" and other lower limb
elements of T. rex are the longest of any animal of it's size.
Allometrically, T. rex is extremely graceful, much more so than the big
allosaurs. It certainly bears no immediate resemblence in structure to a
similarly sized sauropod or elephant.

        There are two, not necessarily completely exclusive, ways to
account for this:
        T. rex has graceful proportions because it moved very quickly for
an animal it's size;
        T. rex has graceful proportions because it had ancestors that
moved very quickly and the proportions are in effect vestiges of cursorial
adaptation. 
        How quickly is "quickly", I don't know. An article Alexander wrote
on the subject noted that speeds for living animals are difficult to
estimate- cheetahs, for example, being quoted as moving anywhere from 50
-70 mph. A lot of these estimates, he noted, are done with less than
professional methods- chasing animals in Jeeps, etc. The same problem
exists with estimating the weights and lengths of living animals- "yeah, I
saw this shark, it was three times the length of my boat, at least!" or
"Ar, we caught a whale, she darned near towed the longboat under- must'n
been near a hundred twenty feet!". 
        I've heard the maximum size of blue whales as anywhere from
100 to 150 tonnes or more- 50% being a pretty big margin of
error. These are living animals we're looking at. So extrapolating the
lengths, weights and speeds of extinct animals is not easy. As for
prey speed- Triceratops has very short metacarpals, but the duckbill
metacarpals are of moderate length. Does anyone remember the top speed
for elephants?

        I would agree that the assumption that T. rex just fell like a
sack of bricks to the ground could be wrong. If you pushed someone to the
ground, they probably wouldn't be hurt, they just respond to catch
themselves. My former room-mate once noted a fainting spell he had; he
ended up knocking out a few of his front teeth he fell so hard. He was
standing still. My former room-mate, of course, is not a T. rex, he is
much smaller, and has much bigger arms, and may have been standing on
concrete or something when he passed out. Still, I tend to think the
damage would have been less if he'd been conscious. Wrestlers and football
players learn how to take falls, and perhaps a T. rex did as well. This
would not eliminate the problem, of course, but it might alleviate it. 

        Response to editorial:
Yes, I'll agree. Jumping all over the conclusions of an eleven year old
kid, for example ;). Granted, said poster did not notice that it had been
an eleven year old kid. I get pretty heated up sometimes too, and I'm
sorry for being overly critical or harsh to anyone. I get kind of riled
up sometimes and sometimes I have a very bad week. We can get kind of
caustic, and sometimes people try to incite others.
        The thing is, there's nothing wrong with ignorance, that's why
this list is here, because of what we don't know about dinosaurs. The only
kind of ignorance that's bad is the kind that refuses to learn. That's
important to realize. You educate the ignorant, instead of insulting them. 
        We probably all need to chill out a little, realize that these
animals are really, really dead, and they probably couldn't care less
about what we think they did. Triceratops may or may not have had some
thermoregulatory ability from its frill, but it sure doesn't have much
anymore. 

        Some hints I've picked up over time, mainly the hard way, and
which I aspire towards, if I don't yet follow them:

---Quote a/the source if you know it. Looking it up is a pain in the ass
sometimes but can be worth it. It gives you ground to stand on and
something to take cover behind. At worst you simply misread something.

---If you've got an argument, evidence is the best ammunition, not things
said about a poster's mother. 

---Use questions, not answers. Saying, "is there any evidence of X" covers
you and is less argumentative than saying "there is no evidence of X". 

---You might want to maybe but not necessarily always just once in a
while use qualifiers possibly sometimes. Again, this might sometimes in
certain circumstances cover what may or may not be your @ss when you make
a statement you just might perhaps possibly have pulled out of your @ss.

---Don't be too certain. People have been proven wrong, even really smart
people who are very respected, like Einstein. Probably nobody here is as
smart as Einstein. We may think we've got the answer, but remember, Ted
Holden, Ed Conrad and Archimedes Plutonium think they've got the answer,
too.