Re: tendaguru question???

["Jaime A. Headden" <qilongia@yahoo.com>]

David Carrizosa (befreeasabird@antimonio.com) wrote:

<It was supposed before that tendaguru was like the morrison formation,
and they used to share dinosaurs like brachiosaurus, barosaurus,
allosaurus, dryosaurus & ceratosaurus. but after that the barosaurus
remains are unofficial called tornieria, and the theropods are quite
indeterminate and brachiosaurus brancai probably will sunk into
giraffatitan, what would happen with dryosaurus lettowvorbecki it's still
considered as the same genus as dryosaurus, or someone think that needs
also reexamination and probably would sunk into dysalotosaurus how it was
previous known, or is too fragmentary the remains to make a good
comparision.>

  *"Barosaurus" africanus* was a renaming to convention for the American
taxon (*Barosaurus lentus*) becuase the two were considered so similar as
to replace any reference to the original genus (Fraas, 1908), *Tornieria
africana*. Currently, this taxon is _still_ considered to be close to
*Barosaurus* and *Diploidocus* from the Morrison, and is a diplodocine, as
opposed to a apatosaurine or other dipldodocid taxon. As a side note, as
*africana* is the original spelling, this name will be retained even if
the taxon is refered to any genus with a masculine gender, as
*Barosaurus*, though the convention at the time (ref., ICZN 2nd and 3rd
eds.) it was referred to *Barosaurus* in the earliy 1900's was to make
gender equal in generic and specific names.

  *"Brachiosaurus" brancai* was granted the name *Giraffatitan*, but this
name still does not mean it is any less related to *Brachiosaurus
altithorax*, from the Morrison; *Brachiosaurus brancai* cannot be sunk
into *Giraffatitan*, rather the first is simply separated in some
aesthetic manner and granted an "equal" rank to make the two species _less
similar_.

  The same issue as above also applies to the so-called distinctions made
between *Dryosaurus altus* and *Dysalotosaurus lettowvorbecki*, for
whatever they are distinguished by, it is an aesthetic drive that
distinguishes a genus from another when the two taxa continue to be
considered each other's closest sister taxon. However one should
distinguish this relationship, or the species, is up to them, but it seems
pointless to refer *D. lettowvorbecki* to *Dryosaurus* since the referral
does not actually contain any additional information and is rather
pointless. You get the same relationship wether there are two pan-Atlantic
species of *Dryosaurus* or two different genera which are as closely
related as the species are in the other structure.

  So, while the Tendaguru has some unique sauropods, as in the
dicraeosaurids *Dicraeosaurus hansemanni* and *D. sattleri*, this does not
reduce the comparative Kimmeridgian/Tithonian fauna between the Morrison
and Tendaguru. They both share dryosaurids, advanced stegosaurids,
brachiosaurids, diplodocids, ceratosaurids, elaphrosaurids, allosaurids,
etc. This faunal composition is known otherwise only in the Lourinha
levels (Portugal), which also appears to have such simialr taxa that they
have been named *Ceratoosaurus* sp., *Torvosaurus* sp., *Allosaurus
fragilis*, as well as camarasaurids, diplodocids, and an allosauroid.
However, all of the Tendaguru species are very well preserved and
supported, save perhaps *D. sattleri*, and this gives us a clear idea that
distinct is similar forms existed between the two formations.

  Cheers,

=====
Jaime A. Headden

  Little steps are often the hardest to take.  We are too used to making leaps 
in the face of adversity, that a simple skip is so hard to do.  We should all 
learn to walk soft, walk small, see the world around us rather than zoom by it.

"Innocent, unbiased observation is a myth." --- P.B. Medawar (1969)

__________________________________
Do you Yahoo!?
SBC Yahoo! DSL - Now only $29.95 per month!
http://sbc.yahoo.com