Agnès Candiotti, Klaus Zuberbühler & Alban Lemasson (2012): Context-related
call combinations in female Diana monkeys. Anim. Cogn. 15(3), 327-339.
Abstract: Non-human primates possess species-specific repertoires of
acoustically distinct call types that can be found in adults in predictable
ways. Evidence for vocal flexibility is generally rare and typically
restricted to acoustic variants within the main call types or sequential
production of multiple calls. So far, evidence for context-specific call
sequences has been mainly in relation to external disturbances, particularly
predation. In this study, we investigated extensively the vocal behaviour of
free-ranging and individually identified Diana monkeys in non-predatory
contexts. We found that adult females produced four vocal structures alone
(?H?, ?L?, ?R? and ?A? calls, the latter consisting of two subtypes) or
combined in non-random ways (?HA?, ?LA? and ?RA? call combinations) in
relation to ongoing behaviour or external events. Specifically, the
concatenation of an introductory call with the most frequently emitted and
contextually neutral ?A? call seems to function as a contextual refiner of
this potential individual identifier. Our results demonstrate that some
non-human primates are able to increase the effective size of their small
vocal repertoire not only by varying the acoustic structure of basic call
types but also by combining them into more complex structures. We have
demonstrated this phenomenon for a category of vocalisations with a purely
social function and discuss the implications of these findings for
evolutionary theories of primate vocal communication.
URL: http://link.springer.com/article/10.1007%2Fs10071-011-0456-8
For reprints please contact Agnès Candiotti (emai:
Magali Pasteau, Davy Ung, Michel Kreutzer & Thierry Aubin (2012): Amplitude
modulation of sexy phrases is salient for song attractiveness in female
canaries (Serinus canaria). Anim. Cogn. 15(4), 639-645.
Abstract: Song discrimination and recognition in songbird species have
usually been studied by measuring responses to song playbacks. In female
canaries, Serinus canaria, copulation solicitation displays (CSDs) are used
as an index of female preferences, which are related to song recognition.
Despite the fact that many studies underline the role of song syntax in this
species, we observed that short segments of songs (a few seconds long) are
enough for females to discriminate between conspecific and heterospecific
songs, whereas such a short duration is not sufficient to identify the
syntax rules. This suggests that other cues are salient for song
recognition. In this experiment, we investigated the influence of amplitude
modulation (AM) on the responses (CSDs) of female canaries to song
playbacks. We used two groups of females: (1) raised in acoustic isolation
and (2) raised in normal conditions. When adult, we tested their preferences
for sexy phrases with different AMs. We broadcast three types of stimuli:
(1) songs with natural canary AM, (2) songs with AM removed, or (3) song
with wren Troglodytes troglodytes AM. Results indicate that female canaries
prefer and have predispositions for a song type with the natural canary AM.
Thus, this acoustic parameter is a salient cue for song attractiveness.
URL: http://link.springer.com/article/10.1007%2Fs10071-012-0492-z
For reprints please contact Davy Ung (email:
Christine R. Dahlin & Timothy F. Wright (2012): Does syntax contribute to
the function of duets in a parrot, Amazona auropalliata? Anim. Cogn. 15(4),
647-656.
Abstract: Complex acoustic signals in many animal species are characterized
by a syntax that governs how different notes are combined, but the
importance of syntax to the communicative function of signals is not well
understood. Mated pairs of yellow-naped amazons, Amazona auropalliata,
produce coordinated vocal duets that are used for territory maintenance and
defense. These duets follow rules that specify the ordering of notes within
duets, such as a strict alternation of sex-specific notes and a defined
progression of note types through each duet. These syntactical rules may
function to define sex-specific roles, improve coordination, and allow
individuals to combine calls into meaningful sequences. As a first step
toward understanding the functional significance of syntax, we conducted two
separate audio playback experiments in which we presented nesting pairs with
normal duets and duets with broken syntax (i.e., one of the syntactic rules
was broken). In Experiment One, we reversed the order of female and male
notes within note pairs while retaining the typical progression of note
types through a duet. In Experiment Two we reversed the order of note types
across a whole duet while retaining the typical female?male ordering within
note pairs. We hypothesized that duets with broken syntax would be
less-effective signals than duets with normal syntax and predicted that
pairs would respond less to broken syntax than to normal duets. Contrary to
predictions, we did not observe differences in response between treatments
for any variables except latency to approach the speaker. After we combined
data across experiments post hoc, we observed longer latencies to approach
the speakers after playbacks of broken syntax duets, suggesting that pairs
could differentiate between playbacks. These responses suggest that breaking
one rule of duet syntax at a time does not result in detectable loss of
signal efficacy in the context of territorial intrusions.
URL: http://link.springer.com/article/10.1007%2Fs10071-012-0493-y
For reprints please contact Christine R. Dahlin (email:
Marisa Hoeschele, Lauren M. Guillette & Christopher B. Sturdy (2012):
Biological relevance of acoustic signal affects discrimination performance
in a songbird. Anim. Cogn. 15(4), 677-688.
Abstract: The fee?bee song of the black-capped chickadee (Poecile
atricapillus) is a two-note, tonal song that can be sung at different
absolute pitches within an individual. However, these two notes are produced
at a consistent relative pitch. Moreover, dominant birds more reliably
produce songs with this species-typical interval, compared to subordinate
birds. Therefore, we asked whether presenting the species-typical relative
pitch interval would aid chickadees in solving pitch interval
discriminations. We found that species-typical relative pitch intervals
selectively facilitated discrimination performance using synthetic sine-wave
stimuli. Using shifted fee?bee song notes from recordings of naturally
produced songs, birds learned the discrimination in fewer trials overall
compared to synthetic stimuli. These results may reflect greater
generalization among stimuli that occur outside species-typical production
parameters. In addition, although sex differences in performance are rarely
observed in acoustic discriminations in chickadees, female chickadees
performed more accurately compared to males.
URL: http://link.springer.com/article/10.1007%2Fs10071-012-0496-8
For reprints please contact Christopher B. Sturdy (email:
Karine Silva, Joana Bessa & Liliana de Sousa (2012): Auditory contagious
yawning in domestic dogs (Canis familiaris): first evidence for social
modulation. Anim. Cogn. 15(4), 721-724.
Abstract: Dogs? capacity to ?catch? human yawns has recently attracted the
attention of researchers in the field of animal cognition. Following recent
studies suggesting that contagion yawning in humans, and some other
primates, is empathy-related, some authors have considered the possibility
that the same mechanism may underlie contagious yawning in dogs. To date,
however, no positive evidence has been found, and more parsimonious
hypotheses have been put forward. The present study explored the
?contagion-only? hypothesis by testing whether the mere sound of a human
yawn can be sufficient to elicit yawning in dogs, in a way that is
unaffected by social?emotional factors. Unexpectedly, results showed an
interesting interplay between contagion and social effects. Not only were
dogs found to catch human yawns, but they were also found to yawn more at
familiar than unfamiliar yawns. Although not allowing for conclusive
inferences about the mechanisms underlying contagious yawning in dogs, this
study provides first data that renders plausible empathy-based, emotionally
connected, contagious yawning in these animals.
URL: http://link.springer.com/article/10.1007%2Fs10071-012-0473-2
For reprints please contact Karine Silva (email:
Kind regards
Sonja
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Dr. Sonja Amoser
Steinrieglstraße 286
3400 Weidlingbach
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