Signal Design Rules Signal design: features and rules Examples Species recognition Courtship Territory defense Conflict resolution Alarm
Signal design features Signal range: context and sender/receiver distance Locatability: cryptic vs conspicuous Duty cycle: % on Identification level: information content -species, sex, individual Modulation potential: stereotyped vs graded Form-content linkage: arbitrary or linked due to source or other constraint
Mate attraction signal rules
Species differences in cricket calls Species differences are encoded in temporal patterns
Species differences in bird song Species differences are encoded in frequency range, INI, note structure
Species differences in firefly flashing signals
Species differences in fiddler crab and fence lizard displays
Species differences in facial patterns
Species differences in moth mate attractant pheromones
Convergence in mate attraction signals Habitat effects Bird song: whistles in forest, trills in open habitats Lizard head bobbing: bob shape on ground, interbob interval for arboreal species Signaling sex and modality Males use auditory or visual signals Females use chemical signals
Courtship signal design rules
Static vs dynamic calling displays Static components: Convey information about species differences. Females prefer mode. Dynamic components: Convey information about individual differences. Females prefer extremes.
Courtship signal and reproductive strategies If paternal care is important, courtship is likely to involve nest building or mate feeding When females are dangerous, courtship signals are often submissive (e.g. spiders) When male dominance is important, courtship signals are often loud, aggressive, and physical
Form-content linkage in courtship
Territory defense signal rules
Territory marking in European badger
Individual differences in territory defense or status signals
Threat signal design rules
Conflict resolution signals
Alarm signal design rules
Avian alarm and assembly calls
Mammal flee vs alert alarm calls California ground squirrel Domestic chicken Belding’s ground squirrel Forest guenon monkey
Visual alarm signals
Across function comparisons If design rules are the result of selection and constraints, expect convergence across taxa More comparative studies are needed to uncover trends in signal form in relation to social function and sender context
Chemical signal differences across functions
Differences in cricket calls across functions
Seasonal patterns in bird coloration differences
Squid color signals