[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

Re: Just So stories and science



<The issue at hand here was whether or not
hypotheses about behavior and evolution of extinct animals can be tested.
It was stated that such hypotheses could not be tested and hence were merely
"just so stories".>

The question could be interpretted more broadly.  From the Pinker discussion
in Natural Language and Natural Selection (url in prior post):
 <Unconvincing adaptationist explanations, which Gould and Lewontin compare
to Kipling's "Just-so stories," are easy to find...Gould and Lewontin
describe a number of nonadaptationist mechanisms that they feel are
frequently not tested within evolutionary accounts: genetic drift, laws of
growth and form (such as general allometric relations between brain and body
size), direct induction of form by environmental forces such as water
currents or gravity, the effects of accidents of history (which may trap
organisms in local maxima in the adaptive landscape), and "exaptation"
(Gould and Vrba, 1982), whereby new uses are made of parts that were
originally adapted to some other function or of spandrels that had no
function at all but were present for reasons of architecture, development,
or history.>

I thought that Dinogeorge's question included the idea that in the absence
of direct observation (sorry!) of the animals, the choice of hypotheses to
examine might be limited by the knowledge and expectations of the person
making the choice.
The examination of testability seemed appropriate in the context of the
response that whatever leads to the choice of a hypothesis, that hypothesis
must live through tests.  The question then becomes whether proving a
hypothesis plausible advances the discussion, given the number of other
possible hypotheses which might also pass plausibility tests using logic,
and also given the need to make choices and assumptions when applying logic.
And the question of the plausible (inference) against the 'demonstrated'
(observation [sorry again]) is interesting, as you know...

Of course, other people can approach the question of reliability of
conclusions a different way.

You might like another quote from the same essay:
<The key point that blunts the Gould and Lewontin critique of adaptationism
is that natural selection is the only scientific explanation of adaptive
complexity. "Adaptive complexity" describes any system composed of many
interacting parts where the details of the parts' structure and arrangement
suggest design to fulfill some function. The vertebrate eye is the classic
example.>

Aren't you glad to be working in a field in which plausibility of adaptive
explanations is assured?