|Phone: +49 (0)521-106 2827|
|2004-2007||Student of Biology at the University of Hanover|
|2007||Bachelor of Science in Biology, Topic: Immunohistochemical Analysis of Neuropeptide Y in the Suprachiasmatic Nuclei of Djungarian Hamsters (Phodopus sungorus)|
|2007-2009||Master's Progamme “Systems Biology of Brain and Behaviour” at the University of Bielefeld|
|2009||Master of Science in Biology, Topic: Dance Behavior and Foraging Preferences of Honey Bees in Response to Variance in Reward|
|since 2010||PhD position at the Department of Evolutionary Biology, supervised by Prof. Dr. Klaus Reinhold|
Effects of anthropogenic noise on acoustic communication in the bow-winged grasshopper (Chorthippus biguttulus)
Various animal species are known to alter their acoustic signals in response to background noise in order to ensure successful signal transmission from sender to receiver. For example, many bird species produce songs with elevated frequencies or higher amplitudes to avoid degradation or masking under noisy conditions. Several frog species respond to high background noise levels with altered calling rates. Mammals often use the “Lombard effect,” i.e. they increase the volume of their acoustic signals relative to background noise. Males of acoustically communicating species are often particularly affected by high noise levels because they frequently produce courtship signals or territorial calls.
Males of the bow-winged grasshopper (Chorthippus biguttulus) produce broadband signals to attract potential mating partners. Females that are receptive and attracted to the courtship song of a male can respond to the male signal with their own short, low-frequency signal. In a first study on song production of male grasshoppers from habitats with different background noise levels, we found that males from noisy roadside habitats produce signals with higher frequencies compared to males from quiet control habitats. More specifically, the lower frequency maximum of male songs from roadside grasshoppers was shifted upwards in comparison to the frequency maximum of males from quiet, rural habitats. For this study, all grasshoppers were recorded under quiet, standardized conditions in the laboratory, which indicates that behavioral plasticity is unlikely as a potential cause of the observed effect.
Male courtship signals play an important role in the context of mate choice in this species. In future studies we want to perform female choice tests and analyze potential female preferences for songs from roadside and rural males. We want to analyze to what degree female preferences are context dependent (regarding the acoustic environment). Additionally, we are interested in the mechanisms behind the difference in local frequency maxima between roadside and rural males and to what extent genotype and environment of the animals play a role with regard to the observed effect.
Acoustic communication, urban noise, phenotypic plasticity, sexual selection, female choice