Time magazine article & metazoans (posted for A. Martin)

From
Date
Reply-To
Date: Fri, 12 Jan 96 09:46:23 -0500
From: PaleoMan@learnlink.emory.edu (Anthony Martin)
Organization: Project LearnLink - Emory University
Subject: Time magazine article & metazoans
To: N.MacLeod@nhm.ac.uk
Priority: normal
MIME-Version: 1.0
Status: O

It was interesting to hear that some people were writing to _Time_ about the
Burgess Shale fauna (article in Dec. 4, 1995 issue) vindicating creationism
because I had a brief discussion with someone about this subject during the
holidays.  One of my family members (by marriage) commented that the
"Biological Big Bang" of the Cambrian makes one think that maybe the Book of
Genesis wasn't that far off the truth.  I replied that there's trace fossil
evidence suggesting metazoan activity 1.2 billion years ago (see Breyer et
al., 1995, in _Geology_, v. 23, n. 3, p. 269-272), long before the Vendozoans
and Cambrian critters started getting body parts preserved.  Additionally, I
pointed out that Vendozoan body and trace fossils preceded the Burgess fauna
by as much as 100 million years.  The response from my family member?
"Opinions, opinions."  <BIG SIGH>  Oh well - it was a pretty good article and
nice to see some aspect of paleontology (besides those big scaley birds from
the Mesozoic that inspire contentious movies) mentioned in a mainstream
article.

Just out of curiousity, what is the conventional wisdom amongst
paleontologists concerning the time of origin for metazoans?  Breyer and
others in their _Geology_  article argue convincingly that they have metazoan
trace fossils in a 1.2 Ga formation, but they note the considerable resistance
some people have to the idea of any metazoans prior to 650 Ma.  I'd like to
hear views from all of you (in the southern part of the U.S., I would say
"y'all" or the plural form, "all y'all") on when critters first started.
Anyone?

Anthony J. Martin
Geosciences Program, Emory University
Atlanta, Georgia, USA