Today, Nelson Alonso turned up on AtBC and turned in an amazing performance that has to be seen to be believed. Alonso is a long-time second-tier “intelligent design” creationism cheerleader; I’ve had experience in online discussions with him since the late 1990s. Some of his braggadocio touched upon having a long history of online discussion. I had a look back at the archives of the Calvin “evolution” email list, where I had some exchanges with Nelson. And I found one such discussion that had an end-point. It even has to do with “irreducible complexity”. I pointed out that the mammalian middle ear ossicular chain is an IC system providing an impedance-matching function, and that the impedance-matching goes away if you remove any of the parts. Nelson tried to deny that this qualified as IC
, at least in part because the fossil record is clear that the system evolved. I’ll quote this last part of the exchange.
Nelson Alonso wrote:
I’m going to put it in one block here before moving on to
responding to Nelson’s post.
MI>People have given examples: The Krebs cycle and the human
MI>inner ear are IC systems (as defined by Behe and asserted by
MI>me) for which means of gradual evolution have been given.
It’s the impedance-matching function of the mammalian *middle*
ear that is proffered as an example. I saw someone today
saying that it is unnecessary to mammalian hearing. This
ignores the fact that every piece is absolutely necessary to
the impedance-matching function. That function goes away
(with about a 30 dB re 1 microbar decrease in sensitivity, or
about 1 / (2^10) the original sensitivity) if any of the parts
are removed. The human blood clotting system, one of Behe’s
examples of IC systems, is not *necessary* to circulation in
much the same way.
WRE>”It’s the impedance-matching function of the mammalian
WRE>*middle* ear that is proffered as an example. I saw
WRE>someone today saying that it is unnecessary to mammalian
WRE>hearing. This ignores the fact that every piece is
WRE>absolutely necessary to the impedance-matching function.
NA>This isn’t true, as I have stated above, one can remove the
NA>entire 3-bone system and I would still hear when pressure
NA>waves hit the oval window.
It is true. The impedance-matching function is lost if any of
the components is removed. As I develop below, there is a
characteristic and significant loss of sensitivity due to the
loss of the impedance-matching function.
My point was not that impedance-matching in the middle ear is
*necessary* to any amount of hearing, but rather that trying
to dismiss the impedance-matching function on the basis that
hearing itself is not completely eliminated is a digression.
One can simulate the loss of sensitivity involved in a gross
manner by donning a good pair of hearing protectors. Trying
to argue that the difference in sensitivity is not a
functional difference seems ludicrous to me.
I suggest that Nelson pick up any good basic text on
audiometry, which will explain about impedance mismatches
going from pressure changes in air to movement of the oval
WRE>That [impedance-matching] function goes away (with about a
WRE>30 dB re 1 microbar decrease in sensitivity, or about
WRE>1 / (2^10) the original sensitivity) if any of the parts
NA>Mere observation can tell us this is false, the one-bone
NA>system of reptiles make them hear quite well.
No, actual experimentation has shown this characteristic loss
of sensitivity in terrestrial mammals to be the case. The
topic of discussion is the function of impedance-matching in
the mammalian middle ear. Normal hearing in another taxon is
not responsive to the point. But Nelson’s digression to
reptilian systems does him no favors. When the middle ear of
lizards is removed, their hearing likewise decreases by 35 to
57 dB in sensitivity, showing the importance of
impedance-matching to acute hearing even outside mammalian
Also, Nelson’s digression shoots him in the foot on another
point, which is that such systems help establish the utility
of simpler systems in accomplishing the same function, which
is a point in favor of evolutionary development of the IC
impedance-matching function of the terrestrial mammalian
I’m a co-author on research that looked at hearing sensitivity
in white whales. Part of that paper discusses the loss of
impedance-matching reported by others in terrestrial mammals
placed in hyperbaric chambers. (You don’t have to use surgery
to reduce the efficacy of the middle ear’s
Sam Ridgway, Donald Carder, Rob Smith, Tricia Kamolnick, and
Wesley Elsberry. 1997. First audiogram for marine mammals in
the open ocean and at depth: Hearing and whistling by two
white whales down to 30 atmospheres. The Journal of the
Acoustical Society of America Volume 101, Issue 5, p. 3136.
WRE>The human blood clotting system, one of Behe’s examples of
WRE>IC systems, is not *necessary* to circulation in much the
NA>Why can’t any one anti-IDist be specific?
What, specifically, does Nelson think is vague about the
statement above? Human circulation occurs even if there is a
problem with the human blood clotting system. Terrestrial
mammalian hearing occurs, at reduced sensitivity, if the
impedance-matching function of the middle ear is compromised.
Trying to dismiss the impedance-matching function of the
mammalian middle ear on the grounds that hearing is not
entirely lost if it is interrupted should likewise cause ID
proponents to reject the example of the human blood clotting
system, which if interrupted does not mean that all
Here’s some of what I’ve written on the topic before.
By irreducibly complex I mean a single system composed
of several well-matched, interacting parts that contribute to
the basic function, wherein the removal of any one of the
parts causes the system to effectively cease functioning.
[End Quote – MJ Behe, Darwin’s Black Box, p.39]
The mammalian middle ear has on one side the tympanum, which
demarcates between middle and outer ear, and on the other the
oval window of the cochlea. In between the two are three
small bones, the malleus, incus, and stapes. These small
bones are articulated in series. What the system of tympanum,
malleus, incus, stapes, and oval window accomplish as a
function is the conversion of high-volume, low pressure
movements of sound in air at the tympanum into low-volume,
high-pressure movements of the oval window and thus the fluid
contents of the cochlea. In tech terms, the system is an
If any component of the system is removed, the
impedance-matching properties of the system go away, and
hearing thresholds are reduced by about 30 dB. With this
system in place, though, hearing can be quite sensitive.
This system appears to make a good match for Behe’s definition
of irreducible complexity. One might wonder why Behe doesn’t
use this instead of mousetraps. Well, one reason is that
there is a fossil record showing forms intermediate between
the reptilian ancestral condition and the mammalian anatomy,
and irreducible complexity doesn’t look so spiffy a concept if
one has to say that IC excludes evolutionary explanation,
except for this case that has been documented as having an