Dear Colleagues,
As the author of the original query, allow me to clarify.
Linguists who study the intonation patterns of English have widely
reported use of the descending minor third in chants and calls (e.g.,
Lieberman; Bolinger) or more generally, in "stereotypical" or
"predictable" speech (Ladd). Similar phenomena have been reported
across many languages (e.g., in Hirst and DiChristo, eds., 1998).
It is frustrating, however, that such claims appear to be mostly
anecdotal rather than empirical. ("Air Ball" is one exception: see
musicologist Cheryl Heaton's article in _PMS_ 1992.) It's more
frustrating still that many linguists tend not to measure pitch with
any precision (and among those who do, some use pitch _difference_
instead of pitch _ratio_!).
Nevertheless, the phenomenon is extremely recognizable to this
English-speaker, and I find the universality claim entirely plausible.
Hence my plea: If anyone knows of any responsible research that bears
on this purported universality, I'd be grateful for the reference.
Now as for my hypothesis. Perhaps "scene analysis" conjured up the
wrong ideas. As Al Bregman writes (here and in his excellent and
well known publications), grouping by pitch proximity is a common
strategy in forming auditory Gestalts. What I'm imagining isn't
grouping but something more like salience or conversely, habituation.
Let's assume a natural environment in which most sounds are noise,
and the few relatively "tonal" sounds (the whistle of the wind, the
creaking of trees) change in pitch only slightly and only slowly.
Then a good way to be heard, or rather, "noticed," would be to
project two clear tones at some significant interval; listeners would
be liable to infer that something non-random (i.e.,
information-laden) had happened.
But of course, as Bregman would also point out, grouping by _timbre_
stands to preserve the unitary identity of the sound source. Since
both the timbre and the loudness of the (amateur) human voice vary
with pitch, the caller faces an opposite constraint as that described
in the previous paragraph. Hence, make the interval big, but not too
big.
(I had been tempted by the critical band but couldn't imagine its
relevance to what is, after all, a _melodic_ phenomenon; I think
Christian Kaernbach's idea is a good one.)
Hope that's clearer. Thank you all for your thoughts, and I welcome more.
Jeremy
--
Jeremy Day-O'Connell
Postdoctoral Fellow in Music Theory
Music Department
University of Chicago
1010 E. 59th St.
Chicago, IL 60637
W (773) 702-8668