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Feedback 2009
Dino proteins and blood vessels: are they a big deal?
Published: 9 May 2009(GMT+10)
Image: Dr Mary Schweitzer
Cells and connective tissue can be clearly seen.
Scott W from the US writes in connection with our recent article
Dinosaur soft tissue and protein—even more confirmation!
I wonder if you could comment on the following blog perspective on this recent find:
I know lots of creationists that get charged up by this sort of thing, since this
is supposed to be evidence that the fossils must be younger than conventional claims
by millions of years. I’ve never been very excited about this, mainly because
the Flood throws a real monkey wrench into these arguments. A major source of degradation
of biomolecules is water. So anything that died in the Flood and floated in water
for a year shouldn’t really have many biomolecules left, right? Seems like
if you believe fossils are millions of years old or are the remains of carcasses
from the Flood, the outcome is the same: very little preservation of biomolecules.
In this case, Schweitzer is finding collagen, which is pretty tough, so I guess
it makes sense that it might be preserved in some extraordinary cases. In any case,
finding the rare, hardy biomolecule from dinosaurs is nothing to get excited about,
since the conventional model and the Flood model both predict the same thing: this
should be very, very unusual.
I think it’s still FAR more plausible for this organic material to survive
water than billions of years, but would love to hear your comments. Perhaps you
could add an ‘update’ to the article.
Drs Carl Wieland and
Jonathan Sarfati reply:
Sure thing.
This blogger must be about the only one, creationist or evolutionist, who
does NOT see this as a problem for the millions of years. Why else would Dr Schweitzer
say she redid one experiment 17 times before she would believe the evidence of her
eyes?1 Why would so many
others express disbelief that these structures could have survived so long, and
why would theories of desperation like biofilms
be invented?
Even the most optimistic predictions had collagen not surviving even 3 million years
at freezing point, and <200,000 years at only 10ºC and < 15,000 years at 20ºC
We have never heard any creationist geologist suggesting that all fossils floated
for a year before being buried. Far from it. Many of the fossils, such as fossil
fish, show remarkable preservation consistent with rapid burial.2 In a complex set of interconnected catastrophes
such as the Flood, one would expect rapid burial by all sorts of sedimentary activity
which may be at any stage of the flood—turbidity currents (submarine landslides),
for example, would have been capable of burying creatures, including even in the
very early stages of the Flood.
Even if the dinosaur carcass were exposed for some weeks or months before being
buried, a creature of such significant size would by no means be exposing all its
organic constituents to degradation, whether by oxygen, bacterial action, or water.
Collagen fibres are often notable on marine carcasses of large creatures, where
the creature as a whole has obviously been decomposing on a beach, exposed to water
at every high tide, for months. This is not a surprising, or even controversial,
observation.
The most likely situation in this sedimentary sandstone which the reports state
encased this particular dinosaur carcass is that the sandstone was deposited over
a relatively brief period of time and that the creature died not long before, or
even as, it was encased in sediment, which subsequently hardened.
Extra water at the time of
the flood would barely affect equilibria; ANY aqueous solution would have
so much excess water that the reaction would be driven to completion
To say that both models predict the same thing really surprises us. The author does
not seem to engage with (or is unaware of) the statements in the articles on our
site (and
those we cite from secular journals) about such fragile molecules falling
apart, even if hermetically sealed, from thermodynamic considerations alone. The
difference in the predictions is stark—even the most optimistic predictions
had collagen not surviving even 3 million years at freezing point, and less than
200,000 years at only 10ºC and less than 15,000 years at 20ºC (in general,
reaction rate increases exponentially with temperature3).
But to explain further why this blogger is in error requires some fairly basic physical
chemistry (the speciality of the second author JS) and organic chemistry (which
he also studied extensively).
In aqueous solutions, water is so much more concentrated than anything else, and
doesn’t change very much (~55.5 mol/kg) so that its activity is treated as
constant when it comes to equilibria. So the extra water at the time of
the flood would barely affect equilibria; ANY aqueous solution would have
so much excess water that the reaction would be driven to completion. The only time
water activity is counted is when the mixture is almost dry so that water
concentration differences then matter.
Generic potential energy diagram showing the effect of a catalyst in a hypothetical
exothermic chemical reaction X + Y to give Z. The presence of the catalyst opens
a different reaction pathway (shown in red) with a lower activation energy. The
final result and the overall (net) thermodynamics are the same. (Diagram from Wikipedia.org)
But most important is the reaction kinetics, i.e. the rate that
the system heads towards equilibrium. The thermodynamic equilibrium depends only
on the free energy differences between starting and end materials
(reactants and products), while kinetics (reaction speed) depends on the free energy
differences between starting material and the transitional state or reaction
intermediate (i.e. activation energy). In simple terms, for the
reaction to occur, some bonds of the reactants must be broken, and this takes energy.
To apply this: a diamond exposed to the air at room temperature is very far from
equilibrium (which would be to form CO2), but the reaction is too slow
to measure because it requires a very high activation energy to break the very strong
bonds [diamond in isolation is not at equilibrium either, but again conversion to
graphite is too slow to notice].
Protein hydrolysis occurs very slowly, even though the equilibrium is far towards
the monomers, because the activation energy is too high. But as research showed,
the reaction would be completed in well under 70 million years. And again, in an
already aqueous solution, extra flood water would make no difference.
What does make a difference is pH: hydrolysis occurs much
faster if catalyzed by acid or alkali (that’s why these are so corrosive
on the skin, which is made of the protein keratin). Note that a catalyst doesn’t
change the equilibrium but provides a different intermediate pathway with a lower
activation energy, speeding up the reaction exponentially (see diagram).
For example, an experiment showed “reaction rate increased proportionally
with hydroxide ion concentration”,4
that is, with increasing pH or alkalinity.
Neutral-buffered waters would serve to retard acid or alkaline hydrolysis.
So the worst thing for hydrolysis is a neutral pH (~7), neither acid (pH
< 7) nor alkaline (pH > 7).5
And ground water and geothermal waters are usually neutral. Not only that, they
are often neutral buffer solutions. A buffer contains weak acidic and alkaline
components that react with added strong acid or alkali, so tends to resist pH changes.
Groundwater tends to dissolve both carbonates (weak alkalis) and CO2
(weak acid), which is why they are buffers6
—blood likewise has this buffer solution to keep it within a narrow pH range,
in this case very weakly alkaline.7
So these neutral-buffered waters would serve to retard acid or alkaline
hydrolysis, contrary to this blogger’s claims.
So the proven rules of chemistry show that both mainstream creationist and mainstream
evolutionists are right to see these dino remnants as a big deal. But for evolutionists,
it’s a problem to be explained away, while it’s a welcome development
under a biblical framework.
Related articles
Further reading
Related resources
References
- Mary Schweitzer, Science 307:1852,
25 March 2005. Return to text.
- Daniel Woolley,
Fish preservation, fish coprolites and the Green River Formation, J. Creation
15(1): 105–111, 2001. Return to text.
- This is the simple Arrhenius rate equation k=Aexp(−Ea
∕RT), where k is the rate constant, A is a temperature-independent constant
(often called the frequency factor), exp is the function ex, Ea is the activation
energy, R is the universal gas constant, and T is the absolute temperature.
Return to text.
- Bruce Robinson and Jefferson Tester,
Kinetics of alkaline hydrolysis of organic esters and amides in neutrally-buffered
solution, International Journal of Chemical Kinetics 22(5):431–448,
30 Sep 2004. Return to text.
- For the chemically minded, pH ≈-log10[H+] (square brackets
mean concentration), and in water [H+][OH–] = 10–14. So neutral water
has a minute concentration of both H+ and OH–, both 10–7 M (at 25°C).
Return to text.
- Kirk Nordstrom,
Pre-mining ground-water quality in debris fans developed from pyrite-mineralized
erosional scars in the Red River Valley, New Mexico: comparison between mined and
unmined areas, Geological Society of America Abstracts with Programs
37(7):395, 18 October 2005: “Ground
waters in bedrock are of neutral pH, buffered by dissolution of carbonate minerals
… .” And Ref. 4 refers to “… neutrally-buffered solutions such as many groundwater and geothermal fluids.” Return to text.
- The pH of a buffer depends on the acidity components and proportions.
For the chemically minded, use the Henderson–Hasselbalch equation pH = pKa +
log10([conjugate base]∕[acid]), where pKa is − log(Ka) where Ka is
the
acid dissociation constant. Return to text.
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