Behaviour 143, 4 (April 2006)
http://www.ingentaconnect.com/content/brill/beh/2006/00000143/00000004
(Abstracts below)
Castellano, S & A Rosso(2006) Variation in call temporal properties and female
preferences in Hyla intermedia. Behaviour 143: 405-424.
Hall, ML (2006) Convergent vocal strategies of males and females are consistent
with a cooperative function of duetting in Australian magpie-larks. Behaviour
143: 425-449.
Hale, AM (2006) The structure, context and functions of group singing in
black-breasted wood-quail (Odontophorus leucolaemus). Behaviour 143: 511-533.
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Castellano, S & A Rosso(2006) Variation in call temporal properties and female
preferences in Hyla intermedia. Behaviour 143: 405-424.
In anurans, long-range advertisement calls are known to convey information
important for both species recognition and mate-quality assessment. To
investigate how these kinds of information are encoded in mating calls, we
carried out two-choice discrimination experiments on female Italian treefrogs,
Hyla intermedia, and examined their patterns of call preferences in response to
variation in fine-scale temporal properties. We analysed preferences for three
fine-scale temporal properties: pulse rate, call duration, and call rise-time.
Calls with the mean pulse rate were significantly preferred over alternatives
with either higher-than-average or lower-than-average pulse rates. The mean
rise-time call was preferred over alternatives with rise-times either close to
or lower than the smallest values recorded in the study population. Unlike
pulse rate and rise-time, females did not show significant preferences for
calls of similar pulse rate, but different call duration. We compare
d female preference functions with the patterns of within-bout variation in
call properties and used these results to illustrate the interactions between
ultimate functions and proximate mechanisms of both call production and
recognition in the co-evolutionary process of the treefrog communication
system.
Hall, ML (2006) Convergent vocal strategies of males and females are consistent
with a cooperative function of duetting in Australian magpie-larks. Behaviour
143: 425-449.
The relationship between the form and function of coordinated acoustic signals
is poorly understood. The coordination of signals by male and female birds to
produce duets could be a cooperative display or a consequence of conflict
between the sexes. Australian magpie-larks (Grallina cyanoleuca) produce
antiphonal duets that function primarily in cooperative territorial defence. I
investigate the form of these duets to determine the individual singing
strategies of males and females and relate these to what is known about duet
function, discussing the implications of variation in the form of duetting
among other species. Male and female magpie-larks both initiate duets, and both
sexes also frequently sing alone. Though males tend to initiate more
vocalisations than females, both are equally likely to join their partners'
songs to form duets. Consistent with the cooperative function of their duets,
the similarity between the sexes in propensity to duet is maintained when duett
ing is less likely during the female fertile period, as well as when it is more
likely during simulated intrusion. Male and female repertoires are similar, and
partners combine their song types non-randomly and with considerable temporal
precision to form duets. The interplay between partners that determines duet
length and precision is consistent with both sexes benefitting from singing
together. The role of duet repertoires and temporal precision in intra- and
inter-pair interactions is poorly understood in magpie-larks and other duetting
species, and requires further investigation.
Hale, AM (2006) The structure, context and functions of group singing in
black-breasted wood-quail (Odontophorus leucolaemus). Behaviour 143: 511-533.
Black-breasted wood-quail (Odontophorus leucolaemus) are vocal, group living
birds (covey size ranges from 2 to 15 individuals) that inhabit the dense
understory of highland forest in Costa Rica. Mated pairs produce coordinated
duets and groups produce coordinated choruses that are audible to humans from a
distance of at least 200 m. Duets and choruses are antiphonal; they consist of
two syllables that are comprised of two elements each, which are repeated over
and over in an alternating fashion. Neighbouring coveys are most often heard
calling back and forth just after dawn and all group members participate in
singing and territory defence. During territorial encounters, group singing is
often accompanied by displays, chases, and even physical fights between members
of opposing coveys. Black-breasted wood-quail produce at least five
structurally distinct close-range calls that are associated with within-group
communication and territorial encounters. Observations of the co
ntext of unprovoked duets and choruses, in addition to responses to simulated
territorial intrusion using playback, indicate that these songs play an
important role in territory advertisement and defence. Furthermore,
black-breasted wood-quail may adjust their response to playback as a function
of relative group size, suggesting that choruses could function in relative
numerical assessment of group size.
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