Page 201 - MODES of EXPLANATION

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experiments fail; the target appears to be unaffected. So perhaps the issue is that the poison is
delivered by the plant so as to be more focused than a simple washing of the poisonous plant.
The response might be to concentrate the fluid, and that works. The difficulty is that the
target suffers, but at that concentration, the poison also debilitates the allelopath itself. This is
a quandary.
The critical experiment that will show allelopathy employs two populations of the
same target species, one with a history of exposure to the poison and another that is naïve
(Geoff Sagar, personal communication). Use whatever concentration of solution it takes,
because the difference between the targets makes for a strong “all else equal.” If the naïve
population suffers more, you have shown allelopathy, but in the more meaningful context of
evolution. The selective advantage of dealing with the poison has changed the exposed
population. In the face of evolution of the target, there is apparently nothing more the
allelopath can do, without poisoning itself. You cannot show allelopathy until it stops
working (Figure 14.4). The essence of the evolved target expects to be assaulted by the
poison. Competition has the same problem with history. What appears to be effects of
competition is in fact “the ghost of competition past” (term coined by Connell, 1980).
[insert Figure 4]
Figure 14.4
The cycles of Zellmer et al. (2006) are applied here to plant chemical
warfare, allelopathy. The wrinkle in time that evolution embodies means that you
cannot show allelopathy until it stops working.
Shifts between Model and Narratives
Narratives are tested by models in a way that encourages improvement. The consistency of
models allows for more confident statements and inference, at least for the local space. The
price of the focus of models is that they are required to be consistent, and that is a limitation.
As models are stretched so as to be questionable, narrative is robust enough to take over.
Inconsistency and contradictions are part of storytelling. In fact, the ability to deal with
narrative gives humans their unique capacity to problem-solve creatively. We readily slip-
slide between different accounts of things until we can find a way through. By changing what
is significant, we can wait until the problem has passed or at least becomes manageable.
There is a relationship equivalent to the dance between model and narrative, that
between experiment and theory. David Bohm, in his
Wholeness and the Implicate Order
,
made some telling remarks:
Thus, in scientific research, a great deal of our thinking is in terms of
theories
. The
word “theory” derives from the Greek “theoria”, which has the same root as “theatre”,
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