>Well, I'll rethink -- but I still think that mere variation such that
>"adopted birds sing songs more like their adopted, not biological, parents"
>is stretching the definition of meme pretty far. If it could be shown
>that, say, a robin can be raised to sing like a chick-a-dee, you'd have me
>convinced.
Here are some of the results of a websearch on Alta Vista for "(birdsongs or
songbirds) and (imitation or learning)":
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TEMPORAL STRUCTURE OF BIRDSONG: THE ROLE OF INNATE KNOWLEDGE Peter Marler
Animal Communication Lab. University Of California Davis, CA 95616-8761,
USA...
URL: www.hip.atr.co.jp/~bateson/hawaii/abstracts/marler_abs.html
"A distinctive pattern of vocal development characterizes birds with learned
songs, including an early phase resembling babbling. Many songbirds
overproduce songs as juveniles, with socially-influenced selective attrition
winnowing the repertoire as maturity approaches. Social factors have a
strong selective influence on which songs are discarded from the repertoire,
by a process called "action-based learning." This is of interest because it
may be phylogenetically more widespread than the typical form, which has
been dubbed "memory-based learning." In the latter, sensitive periods for
song acquisition are typical. Choice of song models for imitations is
non-random, and each species brings distinct patterns of innate knowledge to
bear on the acquisition process, and on song production. Although song
development is based on imitation, many birds also display a high degree of
vocal inventiveness, breaking learned songs down into syllable-like
components and rearranging them into new patterns. This is how large song
repertoires are created, sometimes numbering in the hundreds."
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NEUROBIOLOGY OF BIRDSONG. NEUROBIOLOGY OF BIRDSONG. Introduction. Anatomy of
the Song System (not yet implemented) LIST OF LABORATORIES. By
geographical...
URL:
http://soma.npa.uiuc.edu/courses/physl490b/models/birdsong_learning/bird_son
g.html
"The learning of birdsong has become one of the most popular model systems
in the neuroethology community for understanding how experience modifies the
brain, and interacts with non-experiential aspects.
"The learning of birdsong by developing young is a process that begins with
the production of subsong vocalizations and ends with the production of a
rendition of the tutor's song (usually, the father). The acquisition of
birdsong has a "sensitive period" in some species, including zebra finches,
where interfering with the development of song during this period results in
permanent impairment. In zebra finches, young will form an auditory model of
the tutor's song as early as 20 days after hatching, and song acquisition
will be completed by around 35 days. The song becomes consistent through
rehersal by around 60 days, and crystallizes (becomes invarient) at sexual
maturity, approximately 90 days. Although the development of bird song has a
relatively clear and stereotypic pattern, birdsong's precise role in their
subsequent day-to-day activities is still an area of research."
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THE NATURAL ORIGIN OF LANGUAGE: ARBITRARY OR INNATE
Index Robin Allott. Chapter II. CHAPTER I. LANGUAGE - ARBITRARY OR INNATE.
The generally accepted view of those who study language professionally is
that..
URL: www.percep.demon.co.uk/nol1.htm
"Perhaps even more interesting and relevant for the subject of this chapter
has been research related to imprinting in the development of birdsong.(33)
The course of vocal learning in bird-song resembles that already described
for imprinting in that the young bird is born with an inherited
responsiveness to a broad pattern of external auditory stimulation. In the
course of its experience of the range of sounds in its environment, it
acquires more selective responsiveness to a particular subset of specific
attributes found in the environment.
"If a young bird becomes deaf before it starts to sing, it subsequently
develops a highly abnormal song which is in complete contrast with the
highly controlled, tonal morphology of normal song, that is, the pattern of
song it develops is distorted because of its inability to hear samples of
'normal' bird-song for its species. Perhaps even more relevantly and
interesting, if a young bird with its hearing completely undamaged is raised
in a special restricted environment where it cannot hear any song by others
of its species, it also develops an idiosyncratic song which is abnormal but
diverges less from normal song than does that of the bird deaf from birth.
The song of the isolated bird has a definite patterned morphology, made up
of relatively pure and sustained tones, which however shows a progressive
loss of species-specificity, that is, tends to diverge more and more from
the norm for its species. To put the matter anthropomorphically, a songbird,
like a child, must learn from other birds, if it is to vocalise correctly."
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MPIV. Dept. Wickler. Staff. Publications 1995 1996 1997. Phd-theses.
Diploma-thesis. Wolfgang Wickler - Uta Seibt - Edith Sonnenschein.
Traditive...
URL: http://ss20.mpi-seewiesen.mpg.de/~knauer/waldwee.html
"Traditive behaviour traits
The behaviour of many birds and mammals is markedly influenced by
non-genetically transmitted behaviour programs. Behaviour copied between
individuals is subject to traditive (cultural) evolution. Our studies on
traditive behaviour concentrate on local dialects of two songbird species,
the slate-coloured boubou Laniarius funebris, and the forest weaver Ploceus
bicolor, and on tool behaviour in free-living baboons."
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POPULATION CONSEQUENCES OF INDIVIDUAL BEHAVIOR. ABSTRACTS & REFERENCES.
Susan Alberts. Behavior And Genetic Structure In Primate Societies. My
central...
URL: www.npb.ucdavis.edu/abggpage/abstracts.htm
Jill Soha. Song Learning, Dialects, And Speciation In Passerine Birds.
Song learning is widespread within the avian order passeriformes, or
"perching birds." Song learning is thought in many species to give rise,
over generations, to song "dialects," which are regional variations in song
structure within a species. Does this dialect formation eventually lead to
speciation? I consider a simple proposal in which song learning facilitates
dialect formation, which then leads to population isolation by serving as a
behavioral isolating mechanism, and finally, isolated populations diverge
into distinct species. I review some evidence pertaining to each of these
possible steps. I conclude that dialect formation alone is not very likely
to give rise to speciation, but that in the presence of other (geographical)
reproductive isolating mechanisms, song learning does facilitate speciation
in passerines.
Catchpole, C. K. and Slater, P. J. B. (1995) Bird Song: Biological themes
and variations. Cambridge University Press. Especially Ch. 9, Variation in
time and space.
Kroodsma, D. E. and Miller, E. H. (1982) Acoustic Communication in Birds,
Vol. 2: Song learning and its consequences. Academic Press.
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Baker, Myron C.; Cunningham, Michael A. The biology of bird-song dialects.
Behavioral & Brain Sciences, 1985 Mar, v8 (n1):85-133.
ABSTRACT: Contends that no single theory gives a satisfactory account of the
origin and maintenance of bird-song dialects and that this failure is a
consequence of a weak comparative literature that precludes careful
comparisons among species or studies and of the complexities involved.
Evolution of vocal learning, experimental findings on song ontogeny, dialect
descriptions, female and male reactions to differences in dialect, and
population genetics and dispersal are discussed. A synthetic theory of the
origin and maintenance of song dialects is proposed. It is suggested that
subdialect formation is linked to a theory of the evolution of repertoire
size, but data are too fragmentary to examine this idea critically.
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-Prof. Tim