@article {57950, title = {Listening when there is no sexual signalling? Maintenance of hearing in the asexual bushcricket Poecilimon intermedius}, year = {2007}, abstract = {

Unisexual reproduction is a widespread phenomenon in invertebrates and lower vertebrates. If a former sexual reproducing species becomes parthe- nogenetic, we expect traits that were subject to sexual selection to diminish. The bushcricket Poecilimon intermedius is one of the few insect species with obli- gate but diploid parthenogenetic reproduction. We contrasted characters that are involved in mating in a sexually sibling species with the identical structures in the parthenogenetic P. intermedius. Central for sexual communication are male songs, while receptive females approach the males phonotactically. Com- pared to its sister-species P. ampliatus, the morphology of the hearing organs (acoustic spiracle, crista acustica) and the function of hearing (acoustic threshold) are reduced in P. intermedius. Nonetheless, hearing is clearly maintained in the parthenogenetic females. Natural selection by acoustic hunting bats, pleiotropy or a developmental trap may explain the well main- tained hearing function.

}, keywords = {Auditory ecology, bioacoustics, neuroanatomy, Regression, Vestigialization}, doi = {10.1007/s00359-007-0209-y}, url = {http://link.springer.com/10.1007/s00359-007-0209-y}, author = {Gerlind U.C. Lehmann and Strau{\ss}, Johannes and Lakes-Harlan, Reinhard} } @article {57944, title = {Sensory evolution of hearing in tettigoniids with differing communication systems}, journal = {Journal of Evolutionary Biology}, volume = {27}, year = {2014}, month = {Jan-01-2014}, pages = {200 - 213}, abstract = {

In Tettigoniidae (Orthoptera: Ensifera), hearing organs are essential in mate detection. Male tettigoniids usually produce calling songs by tegminal stridu- lation, whereas females approach the males phonotactically. This unidirec- tional communication system is the most common one among tettigoniids. In several tettigoniid lineages, females have evolved acoustic replies to the male calling song which constitutes a bidirectional communication system. The genus Poecilimon (Tettigoniidae: Phaneropterinae) is of special interest because the ancestral state of bidirectional communication, with calling males and responding females, has been reversed repeatedly to unidirec- tional communication. Acoustic communication is mediated by hearing organs that are adapted to the conspecific signals. Therefore, we analyse the auditory system in the Tettigoniidae genus Poecilimon for functional adapta- tions in three characteristics: (i) dimension of sound-receiving structures (tympanum and acoustic spiracle), (ii) number of auditory sensilla and (iii) hearing sensitivity. Profound differences in the auditory system correlate with uni- or bidirectional communication. Among the sound-receiving structures, the tympana scale with body size, whereas the acoustic spiracle, the major sound input structure, was drastically reduced in unidirectional communicating species. In the unidirectional P. ampliatus group, auditory sensilla are severely reduced in numbers, but not in the unidirectional P. propinquus group. Within the P. ampliatus group, the number of auditory sensilla is further reduced in P. intermedius which lost acoustic signalling due to parthenogenesis. The auditory sensitivity correlated with the size of the acoustic spiracle, as hearing sensitivity was better with larger spiracles, espe- cially in the ultrasonic range. Our results show a significant reduction in auditory structures, shaped by the differing sex roles during mate detection.

}, keywords = {animal communication, insect hearing, regressive evolution, sensory ecology, sensory evolution, tympanal organ}, doi = {10.1111/jeb.2014.27.issue-110.1111/jeb.12294}, url = {http://doi.wiley.com/10.1111/jeb.2014.27.issue-1}, author = {Strau{\ss}, J. and Lehmann, A. W. and Gerlind U.C. Lehmann} } @article {47345, title = {Chromosomal diversification in the flightless Western Mediterranean bushcricket genus Odontura (Orthoptera: Tettigoniidae: Phaneropterinae) inferred from molecular data}, journal = {Journal of Zoological Systematics and Evolutionary Research}, volume = {52}, year = {2014}, month = {Jan-05-2014}, pages = {109 - 118}, abstract = {

We used molecular characters to infer the phylogenetic position of the Western Mediterranean bushcricket genus Odontura and to trace its high karyotype diversity. Analysis of 1391 base pairs of two mitochondrial genes (COI and ND1) and one nuclear sequence (ITS2) was conducted. Phylogenetic topologies were estimated using maximum parsimony, maximum likelihood and likelihood-based Bayesian inference. The genus Odontura is a phylogenetic outlier in respect of all other European Phaneropterinae genera and has been proposed to have originated from a hitherto unknown ancestor. Our results support the monophyly of the genus Odontura and the recognition of two subgenera: Odontura and Odonturella. We found that both Sicilian taxa of the subgenus Odontura have a completely identical morphology and song patterns. Combining these results, we proposed that both should be treated as subspecies: O. (Odontura) stenoxypha stenoxypha and O. (O.) st. arcuata. Bioacoustic data also proved to support independent markers, with song characteristics reflecting the molecular topology. Mapping the karyotypic characters onto the phylogenetic tree allows a reconstruction of the directions and transitional stages of chromosome differentiation. The number of autosomes within the genus Odontura ranges from 26 to 30. In addition to the ancestral X0 sex determination mechanism, neo-XY and neo-X1X2Y sex chromosomes have evolved independently.

}, keywords = {bioacoustics, chromosome evolution, molecular phylogeny, Odontura, Phaneropterinae}, doi = {10.1111/jzs.2014.52.issue-210.1111/jzs.12046}, url = {http://doi.wiley.com/10.1111/jzs.2014.52.issue-2}, author = {Grzywacz, Beata and Klaus-Gerhard Heller and Arne W. Lehmann and Warcha{\l}owska-{\'S}liwa, El{\.z}bieta and Gerlind U.C. Lehmann} } @article {16648, title = {Baseline data for automated acoustic monitoring of Orthoptera in a Mediterranean landscape, the Hymettos, Greece}, journal = {Journal of Insect Conservation}, volume = {18}, year = {2014}, month = {Jan-10-2014}, pages = {909 - 925}, abstract = {

Acoustic emissions of animals serve communi- cative purposes and most often contain species-specific and individual information exploitable to listeners, rendering bioacoustics a valuable tool for biodiversity monitoring. Recording bioacoustic signals allows reproducible species identification. There is a great need for increased use and further development of automated animal sound recording and identification to improve monitoring efficiency and accuracy for the benefit of conservation. Greece, with its high number of endemic species, represents a hotspot for European Biodiversity, including Orthopteran insects. Songs of many Orthoptera might be employed for the inventorying and monitoring of individual species and communities. We assessed the regional spatio-temporal composition of Orthoptera species at the Hymettos near Athens, which is a Natura 2000 site under constant threat due to the surrounding megacity. Within the framework of the EU Life Plus funded AmiBio project, we documented the Orthopteran species\’ habitat characteristics, their co-occurrence and phenology. We found, in total, 20 species with seven to ten Orthoptera at locations characterised by diverse vegetation patterns of perennial herbs and bushes. For the purposes of implemen- tation of an automated remote monitoring scheme, we identified sampling sites with high Orthopteran diversity, allowing the monitoring of all singing Orthoptera within single localities. By analysing sound depositories and adding recordings from new sample individuals, we established a song library as prerequisites for future automatic song detection. Based on our results, acoustic recording units have been placed at remote sites at the Hymettos. We discuss recommendations for further studies to fully employ the potential of automated acoustic monitoring of Orthoptera. A reliable assessment of singing Orthoptera needs recording units covering ultrasound. Due to high attenuation and absorbance by the vegetation, particularly of the high fre- quencies characterising Orthopteran songs, positioning of microphones at sites is critical: the microphone sensor net- work has to be an order of magnitude denser than for mon- itoring birds,

}, keywords = {Autonomous monitoring, Biodiversity monitoring, Orthoptera, sound, wildlife recording}, issn = {1366-638X}, doi = {10.1007/s10841-014-9700-2}, url = {http://link.springer.com/10.1007/s10841-014-9700-2}, author = {Gerlind U.C. Lehmann and Frommolt, Karl-Heinz and Arne W. Lehmann and Riede, Klaus} }