The idea that energy sources can
somehow solve the origins problem is so prevalent that a few detailed examples are
required. A flow of energy can maintain a living or a non-living system in a state of
non-equilibrium. Consider a chemical reaction that proceeds as follows: if the temperature
is less than 25 degrees Celsius, then C –> A + B. If the temperature is above 100
degrees Celsius, then the reaction proceeds in the opposite direction, A+B–> C.
Now consider a body of water that is warmed by volcanic activity (figure 7.5).
Figure 7.5: A Non-Equilibrium System
In figure 7.5, there is a flow of heat from the volcano into the ocean
around it. This sets up a temperature gradient. The water is very hot near the volcano and
very cool away from it. Heat flows in the water as indicated by the arrow. The chemical
reaction under consideration proceeds in the direction to create chemical C near the
volcano. Away from the volcano, it proceeds to create the chemicals, A and B.
Since this creates much more of chemical C near the volcano, C tends to
move away toward the colder water (see arrows). Much more of the chemicals A and B exist
in cold water. So these tend to travel toward the warmer water near the volcano (see
arrows). This creates a cycle in which some chemicals are continually transported from
warm water to cold water, and others from cold to warm.
If the desired chemical is C, then it would be beneficial to heat the
entire body of water to a temperature greater than 100 degrees. If the desired chemical is
A or B, then it would be beneficial to have the entire ocean at a temperature less than 25
degrees Celcius. The flow of energy allows the chemicals to exist away from equilibrium,
but they exist in an intermediate state between the two extremes. There is less of the
chemical C than if the entire body of water is heated to 100 degrees Celsius, but there is
more C than if the entire ocean is at 25 degrees Celsius. The same argument applies to A
and B.
The relevance of such a system to the origin of life is questionable at
best. How this flow of energy and matter can create a complex biological molecule is not
clear. Figure 7.4 is certainly a form of order. C flows to the left, and A and B flow to
the right. The cycle is maintained by the flow of heat, but there is nothing if figure 7.4
that performs the function of an enzyme. There is no mechanism to couple an unfavorable
reaction to a favorable one. Furthermore, there is no mechanism to preferentially create
only the desired chemicals.
Experimental evidence supports this theoretical conclusion. Because
most if not all experiments designed to investigate the origin of complex chemicals make
extensive use of non-equilibrium conditions. The most famous, Miller’s electric
discharge experiment, will be discussed in the next chapter.
So in this case, both theory and experiment converge to the same
answer. Under plausible prebiotic conditions, without molecular knowledge, it is very
difficult (if not impossible) to create the complex chemicals used by life today.
next: Chemical
Oscillators
home: Intelligent Design and the origin of life
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