According to a recent news item entitled: "A new study raises doubts
about fractal patterns in animal behavior", in the ScienceNews e-
letter (week of Dec. 15, 2007) a study by Edwards et al. (2007),
published in Nature of Oct. 25, 2007, casts serious doubts on the
validity of the various claims that have begun to proliferate in the
scientific literature, (starting with albatross birds, in 1996),
search for food by performing Levy flights, or rather Levy searches,
(since the claims by now encompass various walking mammals, in
addition to flying birds and insects, as well as swimming plankton).
According to Edwards et al. the claims are based on the use of
improper methodology and erroneous statistics.
Levy patterns (named after the French mathematician Paul Levy) are
stochastic (chaotic) patterns, resembling Brownian motion, (e.g. the
random motion of a speck of dust in air), but contrary to the
completely random Brownian motion, they are not completely random, but
must satisfy certain rules. A dot traversing a Levy pattern is
expected to show a continuous pattern of clumps, made up of smaller
clumps, made up of even smaller clumps, with occasional long jumps of
random length and direction, followed again by a pattern of ever
smaller clumps", and so on. (The sudden long jumps cannot occur in
Brownian motion.) Levy patterns are based on the very complex math of
fractals, which developed from the math of chaos theory, of which I,
unfortunately, know nothing. Since the formation of Levy patterns
involves a chaotic process, it is, nonetheless, obvious that a humans
could practically produce any number of different Levy patterns that
all start at the same point, but I am unable to determine whether, in
order to produce any Levy pattern, humans must use the underlying
complex math. An analysis by Taylor et al., published in Physics World
of Oct. 1999, appears to show that this is not necessarily the case.
The authors analyzed Jackson Pollock's well known "drip paints", and
concluded that they comprise Levy patterns, even though Pollock knew
nothing of the underlying math, and made the paintings even before the
development of fractal math. The authors claim, however, that his
paintings comprise Levy patterns, only as a result of various specific
rules he had himself imposed on his painting activity, which are rules
that could only have been devised by human "brains". In other words,
even if humans can develop Levy patterns without using the underlying
math, the least they need to use is a high level of human
intelligence. And this, in turn, leads to the conclusion that if any
sub-humans perform Levy searches, their abilities to do so must be
"instinctive", i.e. genetically predetermined; which is the most
im****tant point I needed to arrive at. (Incidentally, Taylor et al.
conclude their analysis with great admiration for Pollock's artistic
achievements, which I do not share at all. But this is besides the
point here.)
Viswanathan, and his colleagues, who were involved in the original
"discovery" osearches provide the best strategy in searching for
objects at random locations. This suggested that the bird's behavior
has adaptive value. Viswanathan is now one of the authors of the newly
published analysis by Edwards et al. (2007), which places the claims
that various sub-humans perform Levy searches in serious doubt.
Now, the well known honeybee "dance language" controversy, (previously
discussed here at length), had long become the most im****tant
reflection of a far more im****tant, general, basic controversy over
the very foundations of the whole field of behavioral science, between
European Ethology, co-sounded by K. Lorenz and N. Tinbergen, (who not
by accident shared the 1973 Nobel Prize awarded to K. v. Frisch for
the "discovery" of the honeybee "dance language", and Schneirla's
School in Behavior, (where the opposition to the honeybee "dance
language" hypothesis sup****ts Schneirla's School vs. European
Ethology).. Very briefly, European Ethology is based on the belief in
the existence of genetically predetermined behaviors, i.e.
"instincts". Schneirla's School, in contrast, is based on a synthesis
of all the ideas that led Lloyd C. Morgan to formulate his well known
Canon, together with the conclusion that all individual traits,
(including behavioral traits), of all living organisms, develop
ontogrnetically, (in the individual organism), under inseparable
effects of both genes and environment, (which, inevitably discredits
the existence of "instincts").
If the honeybee "dance language" exists at all, the ability of
honeybees to use it, must be "instinctive", (and I shall skip the
details here). In spite of an almost endless series of claims to the
contrary, the existence of such a "dance language" has never been, and
never could have been, experimentally confirmed, because the "dance
language" hypothesis was stillborn, (and I again skip the details
here). The 1973 Nobel Committee, however, became erroneously convinced
that the existence of the honeybee "dance language" had already been
fully properly experimentally confirmed; which provided European
Ethology with its most impressive "validation". Hence the joint Nobel
Prize to Lorenz, Tinbergen, and v. Frisch. A publication by Riley at
al. in Nature (of May 12, 2005), suffices to show that more than 30
years after the decision of that Nobel Committee, the claim that
honeybees have a "dance language" still requires a proper experimental
vindication. Have Riley et al. achieved such a vindication? Not at
all! (And I again skip the details here).
The decision of that 1973 Nobel Committee has, however, been the worst
disaster to hit Schneirla's School. It misled very many to, totally
unjustifiably, consider Schneirla's School obsolete, to the point
where they do not even bother to understand what the school really
stands for, let alone use it in their own work.
The newly emerged serious possibility that the whole collection of
very complex "instincts", required to enable various sub-humans, (from
marmot monkeys to invertebrate zooplankton), to perform Levy searches,
may be heading to the waste-basket, is naturally very good news to
the severely, but unjustifiably beleaguered Schneirla's School in
Behavior.
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