110
frequency of E. crossopterum , which resides in relatively quiet pools, but only about
a 10 dB difference for E. fl abellare , which inhabits noisier riffl es.
6 Communicative Value of Acoustic Attributes
In addition to effi cacy of information transfer, acoustic communication trait evolution is infl uenced by its adaptive function to the signaler and/or receiver (Davies
et al. 2012 ). In vertebrate and non-vertebrate animals, sound production can affect
reproductive success by informing female choice, facilitating male detection, and
facilitating male–male resource competition (Searcy and Andersson 1986 ). In fi shes
also, sound production may be signifi cant in infl uencing reproductive success
(Myrberg et al. 1986 ; Amorim and Neves 2007 ; Vasconcelos et al. 2012 ).
Specifi cally, sounds have been linked to female attraction and mate choice (Myrberg
et al. 1986 ; McKibben and Bass 1998 ; Lindström and Lugli 2000 ; Amorim and
Neves 2007 ), and intruder deterrence and threat assessment in the context of territoriality (reviews by Amorim 2006 ; Ladich and Myrberg 2006 ). More broadly,
intraspecifi c variations in fi sh sounds have been related to motivation, individual
variation, social context, and species identity (Amorim 2006 ). This section explores
how acoustic parameters may be honest indicators of male quality, may refl ect
social context, and may refl ect species identity in darters, sculpins, and gobies.
Current evidence indicates that these characteristics can be encoded by sound
amplitude, dominant frequency, duration, and call rate, as has been described for
other fi shes (Bass and McKibben 2003 ).
6.1 Size and Somatic Condition
Fish body size is predictive of success in male–male interactions and territory
defense (Torricelli et al. 1988 ) and is often strongly correlated to reproductive success (e.g., Downhower and Brown 1980 ; Marconato et al. 1989 ). Thus, acoustic
signals that are indices of male size are predicted to provide useful informative to
both potential mates and territorial rivals. In courtship signaling contexts of cavity
spawning fi shes, more specifi cally, females may gain a reproductive advantage by
attending to reliable indicators of successful nest defense and a low likelihood of
cannibalizing eggs (Manica 2004 ). Thus, informative acoustic signals in these fi shes
could also include indices of male somatic condition that predict quality care of
offspring (e.g., high fat reserves) (Amorim et al. 2009 , 2010 ).
Sound pressure level and pulse dominant frequency are reliable indices of body
size in a number of soniferous fi shes (e.g., Myrberg et al. 1993 ; Connaughton et al.
2000 ; Amorim et al. 2008 ). These relationships have also been demonstrated in
some sculpins and gobies, with larger individuals producing sounds with higher
sound pressure levels ( Cottus gobio : Ladich 1989 ; P. minutus , Lindström and Lugli
J.N. Zeyl et al.
frequency of E. crossopterum , which resides in relatively quiet pools, but only about
a 10 dB difference for E. fl abellare , which inhabits noisier riffl es.
6 Communicative Value of Acoustic Attributes
In addition to effi cacy of information transfer, acoustic communication trait evolution is infl uenced by its adaptive function to the signaler and/or receiver (Davies
et al. 2012 ). In vertebrate and non-vertebrate animals, sound production can affect
reproductive success by informing female choice, facilitating male detection, and
facilitating male–male resource competition (Searcy and Andersson 1986 ). In fi shes
also, sound production may be signifi cant in infl uencing reproductive success
(Myrberg et al. 1986 ; Amorim and Neves 2007 ; Vasconcelos et al. 2012 ).
Specifi cally, sounds have been linked to female attraction and mate choice (Myrberg
et al. 1986 ; McKibben and Bass 1998 ; Lindström and Lugli 2000 ; Amorim and
Neves 2007 ), and intruder deterrence and threat assessment in the context of territoriality (reviews by Amorim 2006 ; Ladich and Myrberg 2006 ). More broadly,
intraspecifi c variations in fi sh sounds have been related to motivation, individual
variation, social context, and species identity (Amorim 2006 ). This section explores
how acoustic parameters may be honest indicators of male quality, may refl ect
social context, and may refl ect species identity in darters, sculpins, and gobies.
Current evidence indicates that these characteristics can be encoded by sound
amplitude, dominant frequency, duration, and call rate, as has been described for
other fi shes (Bass and McKibben 2003 ).
6.1 Size and Somatic Condition
Fish body size is predictive of success in male–male interactions and territory
defense (Torricelli et al. 1988 ) and is often strongly correlated to reproductive success (e.g., Downhower and Brown 1980 ; Marconato et al. 1989 ). Thus, acoustic
signals that are indices of male size are predicted to provide useful informative to
both potential mates and territorial rivals. In courtship signaling contexts of cavity
spawning fi shes, more specifi cally, females may gain a reproductive advantage by
attending to reliable indicators of successful nest defense and a low likelihood of
cannibalizing eggs (Manica 2004 ). Thus, informative acoustic signals in these fi shes
could also include indices of male somatic condition that predict quality care of
offspring (e.g., high fat reserves) (Amorim et al. 2009 , 2010 ).
Sound pressure level and pulse dominant frequency are reliable indices of body
size in a number of soniferous fi shes (e.g., Myrberg et al. 1993 ; Connaughton et al.
2000 ; Amorim et al. 2008 ). These relationships have also been demonstrated in
some sculpins and gobies, with larger individuals producing sounds with higher
sound pressure levels ( Cottus gobio : Ladich 1989 ; P. minutus , Lindström and Lugli
J.N. Zeyl et al.