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Re: Sauropod Survival



Entire message included because I bet the archive and lots of people only got the "truncated" error:

----- Original Message -----
From: "Joe Cantrell" <joecntrll@yahoo.com>
To: <dinosaur@usc.edu>
Sent: Tuesday, February 15, 2005 7:12 PM
Subject: Re: Sauropod Survival

David Marjanovic <david.marjanovic@gmx.at> wrote:
----- Original Message -----
From: "Thomas R. Holtz, Jr."
Sent: Monday, February 14, 2005 4:39 PM

In any case, the terrestrial Tr/J extinction event is a weird one. It
seems as if many (if not all) the big non-dinosaurian
archosaurs and non-mammaliaform therapsids were actually extinct by the
Norian-Rhaetian boundary, and didn't make it to the Tr/J
itself. (NOTE: this remains a subject of some debate). So the Tr/J on land
may not be as catastrophic as the P/Tr or the K/T.

How easy, actually, is it to _find_ the Norian-Rhaetian boundary outside of
western/central European marine strata...?


Regardless, the existence of Triassic sauropods does suggest (as you note)
that large metabolically active creatures did survive the event.

_If_ we assume that the hatchlings were not cared for, which means they
didn't need their parents to survive, there could be an easy way around
this. However, this is hard to imagine -- an animal the length of a computer
keyboard plus mouse pad that cannot run caring for itself!


   Joe Cantrell adds these to David Marjanovic's response:

Imagine an energy depleted environment where herbivore populations are beginning to wane and predators are very hungry. The survival of baby sauropods would be problematic in the absence of parental protection even if they didn't rely on their parents for food, not that they could effectively compete with natural low browsers for what was left.

_If_ the Tr-J boundary mass extinction was a global, sudden catastrophe like the K-Pg one, _then_ very few "natural low browsers" and very few predators were left, so all these effects could have canceled each other out. It goes without saying that the Tr-J boundary is less well researched than the K-Pg boundary...


------------------

Your e-mail arrived here as plain text, but _without line breaks_ ( = the lines break wherever the window ends). This means it's not _really_ plain text. This in turn means listproc has found an "attachment" and replaced it by the error message, and this means that some programs (other than Outlook Express which I use) won't display the text.* In all cases I've checked when I get "plain-text" mails without line breaks the archives just contain the error message.

* Outlook Express doesn't display the error message instead. -- Weirder combinations exist. The webmail program on the GMX website displays such e-mails correctly -- _and_ claims the error message is an _attachment_, even though it _doesn't_ do this with HTML mail that I get offlist!