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Re: New Paper

Rahul Daryanani writes:
 > Well, thanks to those who gave me the link. I just had a question
 > about it.  Is it really possible (stesses on possible), that
 > A. fragillmus is a genera or specie of A. altus.

Sure, it's possible.  But not necessarily probable.  That's not
something anyone could pronounce definitively on without comparing the
fossils of both -- and since one of them is gone, that ain't gonna
happen.  So the best we can do is compare the long figure of
_A. fragillmus_ with the _A. altus_ remains, and that's exactly what
Ken did in his paper.  So what you've just read is the state of the
art concerning _Amphicoelias_ species synonymy.

 > Personally, I really doubt it, by looking at the most obvious
 > factor.
 > SIZE. Most of my sources cite A. altus at a maximum of about 80 ft
 > and a minimum of 65 feet, while the minimum I've seen anywhere for
 > A. fragillmus is 130 ft (Paul's estimate), and a maximum of 205
 > ft. That's a difference of more than 200% [...]

Nope -- it's a difference of 100%; it's a _factor_ of 200%.  (Sorry to
be picky, but this mistake is an easy habit to get into.)

 > [...] so I highly dobut that even the most abnormal species could
 > grow so much larger than normal.

Why?  Variation even _within_ species can be far greater than that --
compare a great dane with a toy poodle.  Size is very subject to
evolutionary pressure, and tends to change quickly in all sorts of
circumstances.  For this reason, it's not much used in systematics.

 > Although size is one of the less scientific ways of distinguishing
 > the two species, I'd say it's one of the most obvious. Your
 > thoughts are welcome.

I agree on both counts.  Unfortunately, much of what is "obvious"
turns out to be wrong :-)

 _/|_    ___________________________________________________________________
/o ) \/  Mike Taylor    <mike@indexdata.com>    http://www.miketaylor.org.uk
)_v__/\  "In Italy you are always on shaky ground.  You can be top of
         the league, have a bad team photo and be sacked" -- Ron Atkinson.