[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]
Re: Nycto fingers
> Sorry to be a day late. If I'm not copied I only get the DML mail when I
> read the archives.
> > So you suggest the following scenario: first the skin, muscles and
> > connective tissue rots away, then the cartilage is impressed, and then
> > the cartilage rots away? Because... this isn't going to happen. The
> > cartilage will have finished rotting before the skin.
> Occam's razor aside, not sure we're talking about ordinary cartilage >
> bone here.
What else? Phalanges are ordinary endochondral bones. They start as
cartilage and then turn gradually into bone.
> And not sure we're talking about rotting away here. Something
> is maintaining a shape long enough for an impression to be made.
We're not talking about, say, dissolution of bone in acidic groundwater.
This would not have so neatly affected some bones and spared their
neighbours -- all bones of a vertebrate skeleton are made of the very same
material in the same crystal structure; and it would have dissolved the
limestone around the bones _first_ (calcium carbonate is less resistant to
acids than calcium phosphate).
We're not talking about cartilage, see above.
Then what else would you suggest?
> all I know. In this case it might be better to start with the
> observation and come up with an explanation later.
It might, of course -- but that "later" is _now_. :-)
> Otherwise, you'll see it all in Denver.
Pretty certainly not. It wouldn't be easy to leave in the middle of the
semester; I might have to stand in some lab in that week in November, for
example. Why can't they put it into September?
> And in the meantime, follow the technique and check it
> out for yourself.
I have only IrfanView (I'm not going to spend 1000 $ on Photoshop or Corel),
and I don't have a high-resolution photo of... pretty much any fossil. And
most importantly, I couldn't check my findings against a specimen. What if
that promising dark spot is just hardening glue in excessive thickness? What
if it's merely the only place on the slab where iron(III)-breathing bacteria
didn't reach before the groundwater table fell below it?
Worse yet, in order to find 3D structures, I'd obviously need multiple
photos of the same specimen from different angles.