Re: New falsifiable proposal/prediction of design


Wall of Sleep wrote:
> floyd wrote:
>
> > Wall of Sleep wrote:
> >
> > [snip]
> >
> > Interesting proposal, but not falsifiable.
> >
> >
> >>I have no idea where the barrier lies for each individual genus (don't
> >>know if that's the correct term?),
> >
> >
> >
> > The above is the bit that needs work. It's not a falsifiable
> > prediction unless and until you can state explicitly where that barrier
> > is supposed to be.
> >
> > You don't need to state a general rule for _every single_ genus (or
> > species, or whatever taxonomic level interests you). You could simply
> > state that the location of the barrier is an empirical issue that must
> > be determined on a case-by-case basis.
> >
> > _But_ if you want this proposal to be falsifiable, you need to suggest
> > (1) where the barrier exists for at least _one_ pair of organisms, and
> > (2) what it should look like. You seem to be proposing that viability
> > of the organism is an indicator of the barrier. That's fine, although
> > there are many other known causes of failure of viability, so you need
> > to be able to exclude those as well. (For example, my great
> > grandfather died, but *not* because he suddenly developed a mutation
> > that caused him to exceed the boundaries of "human", wherever those
> > boundaries might be.)
> >
> > I look forward to seeing the modified version of your proposal. A more
> > modest version, detailing the location and nature of the barrier in one
> > and only one specific case, may potentially be falsifiable. The more
> > general speculation ("that a barrier exists somewhere but we don't know
> > where or what it looks like") is, let's say, "not yet ready for
> > publication".
> >
>
> I don't know that I have the expertise to show exactly where a barrier
> exists to your satisfaction.


But you see, that's exactly the problem. If I were to say to you "I
bet you ten dollars that you can't walk all the way to point X", the
first thing you would say is "where is point X?" If I replied "I
can't tell you that." You'd probably think it was a rather silly bet.


We're faced with the same problem here. You tell me that evolution
can't go beyond a specific point, so I have to ask where that point can
be found. If you can't tell me, I have no way to determine if you are
right or not.


> Like I said, I'm no biologist. My guess is
> that most of the "gaps" in the fossil record represent barriers of this
> type.
>


Are there specific "gaps" you're thinking about here? I often hear
people say that there are gaps in the fossil record, but it's very rare
that anyone ever points to a specific gap.

It's quite clear that the fossil record is not a complete set of the
preserved remains of all organisms that ever lived. (Good thing too,
or we would have no food!) The reasons that the fossil record is not a
complete biotic record are also pretty well understood. But I don't
understand why the _absence_ of preserved remains can be extrapolated
to imply that the organisms never existed. As an analogy, if I found a
book with a few missing pages, I would assume someone tore them out or
that the book was in some way incomplete, but I would not assume that
the pages were never written.



> My proposal would mean that these barriers represent a need for original
> "types" or "kinds", and that through experimentation, the genetic
> borders for these original kinds can be found.


Ok, so this is an empirical project exclusively. That's fine.



> The simplest experiment
> would probably be the evolution of multi-celled organisms from
> single-celled.


Ok, but that's already been done. See Velicer, Gregory J. and Yuen-tsu
N. Yu. 2003. _Evolution of novel cooperative swarming in the bacterium
Myxococcus xanthus_. Nature 425: 75-78

and

Rainey, Paul B. and Katrina Rainey. 2003. _Evolution of cooperation
and conflict in experimental bacterial populations_. Nature 425: 72-74.



> Essentially, if it can be done, then both evolved from an
> original kind. If not, then seperate kinds were necessary.


So single celled life (like yeast and bacteria) and multicellular life
(such as giant sequoias and humans) both evolved from the same original
kind. Gotcha. So where, exactly, do you see a problem with evolution?



>
> If a moth can be genetically altered into a butterfly, then it can be
> presumed both are of the same kind. I would suspect that this might be
> possible. I would guess however that a moth could not be altered into a
> bee. If it could, a common ancestor is "proven", or at least shown to be
> probable.


Wait a second, a single ancestor of both bacteria and sequoias is ok,
but a shared ancestor between moths and bees isn't? I'm not following
you here. Could you clarify this please. It seems like a
contradiction to me, but perhaps I'm just misunderstanding.


>
> I should add that such barriers are already being found. For instance,
> in Hall's E-coli experiments, where a lactase enzyme evolved quickly,
> when the evolved gene was deleted, no new gene evolved. He said himself
> that these bacteria had "limited evolutionary potential."


in B.G. Hall, _Evolution on a Petri Dish. The Evolved B-Galactosidase
System as a Model for Studying Acquisitive Evolution in the
Laboratory_, Evolutionary Biology, 15(1982): 85-150.

In this case, "limited potential" may not mean what you think it means.
Hall removed one enzyme that broke down lactose and the species very
quickly evolved a replacement by modification of a different existing
enzyme. He then removed both of those enzymes and found that doing so
prevented the organism from utilising lactose. No third set of genes
was available to be modified to code for lactase. (Of course that's
like saying that humans have "limited potential for running" because if
you cut off both of someone's legs, they aren't going to win any
marathons!) The removal of the two lactase sequences did _not_ prevent
the organisms from using glucose, so even that rather extreme form of
artificial manipulation didn't result in the death of the organisms,
which was the criteria you had proposed previously.


>
> Also, it should be noted, that this proposal can also be falsified in
> reverse. If a bat can be "reverse evolved" into a rat, or a bird to a
> lizard, etc., the proposal would be falsified.
>


Is there something about the flying squirrel that causes you to reject
it as "half-way" between a rat and a bat? It looks like exactly the
sort of thing you're looking for. (Of course it is not an _actual_
ancestor or descendent of either, but it does show how that "gap" can
be bridged.)


> Theoretically, it should be possible to reverse evolve any lifeform back
> to a previous state and eventually all the way back to an original
> single cell.

It is, of course, quite easy to build a human starting with a single
cell. My mom did it four times!
;-)


> I know this would take too long to be reasonable, but any
> steps along the way should also be possible. I say they're not. But
> since I'm no scientist, and have no access to a lab (and wouldn't know
> what to do there if I did!), I'll leave the testing to the experts.
>
> Those of you that claim it's already been done, please cite the exact
> experiments and their results.

See above for the citations on single-celled to multi-celled. It seems
to me that if _that_ has been accomplished, any other observed
instances are pretty much redundant. If we have a "bridge" between
bacteria and beluga whale, the bridge between moths and bees is a
pretty simple one to accept. YMMV, of course, but I'd like to hear
your take on that. Thanks, again. I appreciate your ideas (even
though I disagree).

.