290 likes | 366 Views
This critical examination explores how symmetry impacts communication in Gryllus bimaculatus. Male crickets sing to attract females, with their harp size and call characteristics correlated with symmetry. Females prefer symmetrical males based on acoustic cues. The study delves into the relationship between wing morphology, asymmetry, and female choice, shedding light on the acoustic preferences of both genders.
E N D
The importance of symmetry in an insect communication system. A critical examination of “Symmetry in the songs of crickets” Simmons & Ritchie (1996) Luke Verburgt Prof J.W.H. Ferguson Dr T. Weber
Introduction Males sing to attract females Gryllus bimaculatus
Introduction Bandwidth 0.4kHz 5.3 kHz 4.9 ~ 150ms
Introduction FA Fluctuating Asymmetry (R-L) Developmental Instability
Introduction DA Directional Asymmetry (R-L) Genetically determined
Simmons & Ritchie (summary) • MALES • Harp size is correlated with body size • Call frequency is correlated with harp size • Call bandwidth is correlated with DA of harp • FA morph is correlated with DA of harp • Therefore: Females can “hear” how symmetrical a male is • FEMALES • Prefer pure-tones indicative of a symmetrical male • Therefore: • Females can “choose” symmetrical males acoustically
Conclusion for Males • Harp size is correlated with body size • Call frequency is correlated with harp size • Call bandwidth is correlated with DA of harp • FA morph is correlated with DA of harp Therefore: Females can NOT“hear” how symmetrical a male is
Kramer spherical treadmill Speaker Cricket Sphere
Female frequency response…. y = -0.7364067647x8+30.9904983205x7-563.878302226x6+5795.0167254032x5-36803.3533238713x4+147952.6446x3-367735.2038x2+516575.2812x-313757.8008
Multiple regression…. Area under BW curve 1) Area under Frequency curve 2) Poly-predicted Frequency preference F2,109 = 15.24; R2 = 0.22; p<0.001 Area under Frequency curve p=0.008 Poly-predicted Frequency preference p = 0.005
Conclusion for Females • FEMALES • Prefer pure-tones indicative of a symmetrical male • Therefore: • Females can NOT “choose” symmetrical males acoustically rather A female will tolerate a certain bandwidth range which is pre-defined by her frequency response range
Acknowledgements • Dr. H.U. Kleindienst • Heidrun Bamberg Funding & logistics • Dr. Xim Cerda • Marna Ferreira