phasianid studied, bobwhite quail, shows no evidence of any kind of vocal
learning (Table 4.1).
The only mammalian vocalizations that seem to allow for learned acquisition are whistle signatures in bottlenose dolphins and song themes in
humpback whales. Learned acquisition is implied, but not demonstrated, by
the appearance of shared whistle types in dolphin repertoires and by the
addition of new, shared themes to humpback songs. These instances suggest
learned acquisition because complete vocalization types are shared and
seem to appear relatively intact in individual repertoires after hearing them
in socially relevant contexts. Current data are insufficient to rule out social
modification as a mechanism for sharing of call types. Individual repertoires
of dolphins appear to be large and are incompletely known; thus, whistle
sharing could reflect a change in how often an individual produces a particular whistle that it already knows rather than acquisition of a novel type.
Experiments should be conducted and published to test directly the importance of learned acquisition to whistle structure in dolphins. Unfortunately,
experimental tests in humpbacks would be difficult.
The types of vocalizations that are acquired through learning include
both song and contact calls that function as group and individual signatures
and show dialect variation in birds and possibly mammals.This suggests that
similarity to others is important in all types of vocalizations.
5.1.2. Patterns of Social Modification Compared
Social modification seems to be a widespread mechanism of vocal learning
both in birds and in mammals.Again, birds from all three groups show social
modification (Table 4.3). Convergence in frequency features of chickadee
D notes depends on social modification in adults, although temporal features and note-type proportions do not seem to rely on any form of vocal
learning. Juvenile budgerigars incorporate many frequency features and
some temporal features of social partners’ calls into their contact calls.
Vocal plasticity persists into adulthood in this species also because the adult
members of social groups give similar contact calls and males sing similar
warble song. As with chickadees, some call and song features do not rely
on learning. The structure of individual notes and the temporal pattern of
song is shared by Anna hummingbird males raised together, suggesting that,
in addition to learned acquisition, social modification influences song structure in this species. In addition, individual Australian magpies share songs
with their group mates (Table 4.1).
The incidence of social modification in mammals, including bats and
cetaceans but not nonhuman primates, is more widespread than for learned
acquisition (Tables 4.2 and 4.3). Lesser spear-nosed bat infants appear to
modify frequency and temporal features of their isolation calls to increase
similarity to their mothers’ directive calls. Greater spear-nosed bat females
change the fine structure of screech calls, including frequency and
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J.W. Boughman and C.F. Moss
learning (Table 4.1).
The only mammalian vocalizations that seem to allow for learned acquisition are whistle signatures in bottlenose dolphins and song themes in
humpback whales. Learned acquisition is implied, but not demonstrated, by
the appearance of shared whistle types in dolphin repertoires and by the
addition of new, shared themes to humpback songs. These instances suggest
learned acquisition because complete vocalization types are shared and
seem to appear relatively intact in individual repertoires after hearing them
in socially relevant contexts. Current data are insufficient to rule out social
modification as a mechanism for sharing of call types. Individual repertoires
of dolphins appear to be large and are incompletely known; thus, whistle
sharing could reflect a change in how often an individual produces a particular whistle that it already knows rather than acquisition of a novel type.
Experiments should be conducted and published to test directly the importance of learned acquisition to whistle structure in dolphins. Unfortunately,
experimental tests in humpbacks would be difficult.
The types of vocalizations that are acquired through learning include
both song and contact calls that function as group and individual signatures
and show dialect variation in birds and possibly mammals.This suggests that
similarity to others is important in all types of vocalizations.
5.1.2. Patterns of Social Modification Compared
Social modification seems to be a widespread mechanism of vocal learning
both in birds and in mammals.Again, birds from all three groups show social
modification (Table 4.3). Convergence in frequency features of chickadee
D notes depends on social modification in adults, although temporal features and note-type proportions do not seem to rely on any form of vocal
learning. Juvenile budgerigars incorporate many frequency features and
some temporal features of social partners’ calls into their contact calls.
Vocal plasticity persists into adulthood in this species also because the adult
members of social groups give similar contact calls and males sing similar
warble song. As with chickadees, some call and song features do not rely
on learning. The structure of individual notes and the temporal pattern of
song is shared by Anna hummingbird males raised together, suggesting that,
in addition to learned acquisition, social modification influences song structure in this species. In addition, individual Australian magpies share songs
with their group mates (Table 4.1).
The incidence of social modification in mammals, including bats and
cetaceans but not nonhuman primates, is more widespread than for learned
acquisition (Tables 4.2 and 4.3). Lesser spear-nosed bat infants appear to
modify frequency and temporal features of their isolation calls to increase
similarity to their mothers’ directive calls. Greater spear-nosed bat females
change the fine structure of screech calls, including frequency and
198
J.W. Boughman and C.F. Moss