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repertoire of Cottus gobio , Cottus perifretum , and Cottus rhenanus consists
predominantly of single knocks and occasional structured knock trains (Ladich
1989 ; Colleye et al. 2013 ). Cottus gobio knocks have been documented in agonistic contexts and are also presumed to be involved in courtship, since “head nods”
were visually observed during courtship and head nods are always accompanied by
knocks (Morris 1954 ; Ladich 1989 ). Cottus bairdii and Cottus paulus produce
knocks and knock trains in both agonistic and courtship contexts (Whang and
Janssen 1994; Kierl and Johnston 2010 ). The tonal moan of Cottus carolinae is
produced in agonistic contexts but is produced at a lower rate relative to “knocks”
(DEH, unpublished).
Knocks have been described in several distinct clades across the Cottus phylogeny (in phylogenetic order from Kinziger et al. 2005 ): Cottus clade: Cottus gobio
(Ladich 1989 ), C. perifretum , C. rhenanus (Colleye et al. 2013 ); Uranidea clade: C.
carolinae , C. bairdii (Whang and Janssen 1994 ), C. paulus (Kierl and Johnston
2010 ); Bailkalian clade: Cottocemephorus grewingkii (Whang 1992, see Whang
and Janssen 1994 ). The prevalence of the knock sound may indicate that it is an
ancestral sound type within Cottus and that the moan of C. carolinae is a derived
condition. However, the ancestral sound type of Cottidae more broadly remains an
open question because of a lack of data. Myoxocephalus , with its harmonic “growls”,
is basal to both Cottus and Leptocottus (Yokoyama and Goto 2005 ). Acoustic signaling is likely widespread in Scorpaeniformes, as both single pulses and harmonic
sounds have also been found in rockfi shes (Širović and Demer 2009 ) and sea robins
(Amorim 2006 ). Hallacher ( 1974 ) identifi ed swim bladder-associated drumming
muscles in many Sebastes rockfi shes.
2.3 Gobies
Sound production has been documented in 22 species of goby (Table 2 ), which is a
large number within a soniferous group, but a small proportion of the ~1950 goby
species described (Nelson 2006 ). In fact, less than 2 % of the entire group have been
acoustically tested. In 16 of the 22 goby species described to date, sound structures
are strictly pulsatile. In the remaining six species, tonal components have been
recorded either as the exclusive repertoire or combined with pulsatile components
into “complex” sounds (Lugli et al. 1997 ) (Table 3 ). Regardless of temporal structure, the average peak frequency of sounds emitted by gobies is low (~100–150 Hz)
with few exceptions reaching the 300–450 Hz range. Mok ( 1981 ) described sound
energy above 1 kHz in Gobiosoma bosc , though the sound recording likely masked
most sounds below ~750 Hz. The only goby species for which no sound production
has been detected despite thorough investigation is Economidichthys pygmaeus
(Gkenas et al. 2010 ), a small freshwater species which lacks burrowing behaviour,
instead using naturally occurring reedstand cavities. This was interpreted as a secondary loss of sound production, due probably to the peculiar ecological conditions
that characterized the evolution of this species (Gkenas et al. 2010 ).
Convergent Aspects of Acoustic Communication in Darters, Sculpins, and Gobies
repertoire of Cottus gobio , Cottus perifretum , and Cottus rhenanus consists
predominantly of single knocks and occasional structured knock trains (Ladich
1989 ; Colleye et al. 2013 ). Cottus gobio knocks have been documented in agonistic contexts and are also presumed to be involved in courtship, since “head nods”
were visually observed during courtship and head nods are always accompanied by
knocks (Morris 1954 ; Ladich 1989 ). Cottus bairdii and Cottus paulus produce
knocks and knock trains in both agonistic and courtship contexts (Whang and
Janssen 1994; Kierl and Johnston 2010 ). The tonal moan of Cottus carolinae is
produced in agonistic contexts but is produced at a lower rate relative to “knocks”
(DEH, unpublished).
Knocks have been described in several distinct clades across the Cottus phylogeny (in phylogenetic order from Kinziger et al. 2005 ): Cottus clade: Cottus gobio
(Ladich 1989 ), C. perifretum , C. rhenanus (Colleye et al. 2013 ); Uranidea clade: C.
carolinae , C. bairdii (Whang and Janssen 1994 ), C. paulus (Kierl and Johnston
2010 ); Bailkalian clade: Cottocemephorus grewingkii (Whang 1992, see Whang
and Janssen 1994 ). The prevalence of the knock sound may indicate that it is an
ancestral sound type within Cottus and that the moan of C. carolinae is a derived
condition. However, the ancestral sound type of Cottidae more broadly remains an
open question because of a lack of data. Myoxocephalus , with its harmonic “growls”,
is basal to both Cottus and Leptocottus (Yokoyama and Goto 2005 ). Acoustic signaling is likely widespread in Scorpaeniformes, as both single pulses and harmonic
sounds have also been found in rockfi shes (Širović and Demer 2009 ) and sea robins
(Amorim 2006 ). Hallacher ( 1974 ) identifi ed swim bladder-associated drumming
muscles in many Sebastes rockfi shes.
2.3 Gobies
Sound production has been documented in 22 species of goby (Table 2 ), which is a
large number within a soniferous group, but a small proportion of the ~1950 goby
species described (Nelson 2006 ). In fact, less than 2 % of the entire group have been
acoustically tested. In 16 of the 22 goby species described to date, sound structures
are strictly pulsatile. In the remaining six species, tonal components have been
recorded either as the exclusive repertoire or combined with pulsatile components
into “complex” sounds (Lugli et al. 1997 ) (Table 3 ). Regardless of temporal structure, the average peak frequency of sounds emitted by gobies is low (~100–150 Hz)
with few exceptions reaching the 300–450 Hz range. Mok ( 1981 ) described sound
energy above 1 kHz in Gobiosoma bosc , though the sound recording likely masked
most sounds below ~750 Hz. The only goby species for which no sound production
has been detected despite thorough investigation is Economidichthys pygmaeus
(Gkenas et al. 2010 ), a small freshwater species which lacks burrowing behaviour,
instead using naturally occurring reedstand cavities. This was interpreted as a secondary loss of sound production, due probably to the peculiar ecological conditions
that characterized the evolution of this species (Gkenas et al. 2010 ).
Convergent Aspects of Acoustic Communication in Darters, Sculpins, and Gobies