@article {58055, title = {MATE CHOICE IN TREE CRICKETS AND THEIR KIN}, year = {1999}, abstract = {

Mate choice theory has become a major field of research in behavioral ecology. Tree crickets provide excellent opportunities for studying the diversity and variability of mate choice. The evidence for female mate choice in tree crickets is reviewed, and broad comparisons with other orthopteran groups are made. The evidence shows that female choice may occur during several different stages of mating and may target several different criteria. Song preferences are perhaps dominated by stabilizing preferences for the cues of species recognition, but there is a growing body of evidence for directional preferences based on sensory biases or mate quality. Mate rejection during courtship and forms of postcopulatory choice may favor males, based both on phenotypic quality and on the amount of nutritious courtship gifts they provide, and may differ with the value of mating incentives. Understanding the balance and trade-offs between different forms of mate choice may help in understanding their evolutionary causes.

}, keywords = {courtship feeding, Female choice, Gryllidae, Orthoptera, sexual selection}, doi = {10.1146/annurev.ento.44.1.371}, url = {http://www.annualreviews.org/doi/10.1146/annurev.ento.44.1.371}, author = {Brown, W. D.} } @article {57935, title = {Savannah roars: The vocal anatomy and the impressive rutting calls of male impala (Aepyceros melampus) {\textendash} highlighting the acoustic correlates of a mobile larynx}, year = {2019}, abstract = {

A retractable larynx and adaptations of the vocal folds in the males of several polygynous ruminants serve for the production of rutting calls that acoustically announce larger than actual body size to both rival males and potential female mates. Here, such features of the vocal tract and of the sound source are documented in another species. We investigated the vocal anatomy and laryngeal mobility including its acoustical effects during the rutting vocal display of free-ranging male impala (Aepyceros melampus melampus) in Namibia. Male impala produced bouts of rutting calls (consisting of oral roars and interspersed explosive nasal snorts) in a low-stretch posture while guarding a rutting territory or harem. For the duration of the roars, male impala retracted the larynx from its high resting position to a low mid-neck position involving an extensible pharynx and a resilient connection between the hyoid apparatus and the larynx. Maximal larynx retraction was 108 mm based on estimates in video single frames. This was in good concordance with 91-mm vocal tract elongation calculated on the basis of differences in formant dispersion between roar portions produced with the larynx still ascended and those produced with maximally retracted larynx. Judged by their morphological traits, the larynx-retracting muscles of male impala are homologous to those of other larynx-retracting ruminants. In contrast, the large and massive vocal keels are evolutionary novelties arising by fusion and linear arrangement of the arytenoid cartilage and the canonical vocal fold. These bulky and histologically complex vocal keels produced a low fundamental frequency of 50 Hz. Impala is another ruminant species in which the males are capable of larynx retraction. In addition, male impala vocal folds are spectacularly specialized compared with domestic bovids, allowing the production of impressive, low-frequency roaring vocalizations as a significant part of their rutting behaviour. Our study expands knowledge on the evolutionary variation of vocal fold morphology in mammals, suggesting that the structure of the mammalian sound source is not always human-like and should be considered in acoustic analysis and modelling.

}, keywords = {Bovidae, Felidae, formants, fundamental frequency, larynx retraction, mammal, polygyny, roaring, ruminant, sexual selection, vocal fold, vocal posture, vocal tract}, doi = {10.1111/joa.13114}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1111/joa.13114}, author = {Frey, Roland and Volodin, Ilya A. and Volodina, Elena V. and Efremova, Kseniya O. and Menges, Vera and Portas, Ruben and Melzheimer, J{\"o}rg and Fritsch, Guido and Gerlach, Christina and D{\"o}rnberg, Katja} } @article {57625, title = {Call Characteristics of Two Sympatric and Morphologically Similar Tree Frogs Species, Polypedates megacephalus and Polypedates mutus (Anura: Rhacophoridae), from Hainan, China}, year = {2018}, abstract = {

Anuran calls are usually species-specific and therefore valued as a tool for species identification. Call characteristics are a potential honest signal in sexual selection because they often reflect male body size. Polypedates megacephalus and P. mutus are two sympatric and morphologically similar tree frogs, but it remains unknown whether their calls are associated with body size. In this study, we compared call characteristics of these two species and investigated any potential relationships with body size. We found that P. megacephalus, males produced six call types which consisting of three distinct notes, while P. mutus males produced five types consisting of two types of notes. Dominant frequency, note duration, pulse duration, and call duration exhibited significant interspecific differences. In P. megacephalus, one note exhibited a dominant frequency that was negatively correlated with body mass, snout-vent length, head length, and head width. In P. mutus, the duration of one note type was positively correlated with body mass and head width. These differences in call characteristics may play an important role in interspecific recognition. Additionally, because interspecific acoustic variation reflects body size, calls may be relevant for sexual selection. Taken together, our results confirmed that calls are a valid tool for distinguishing between the two tree-frog species in the field.

}, keywords = {body size, call characteristics, Polypedates, sexual selection}, author = {Qiucheng LIU and Tongliang WANG and Xiaofei ZHAI and Jichao WANG} } @article {57610, title = {Noisy neighbours among the selfish herd: a critical song distance mediates mate recognition within cicada emergences (Hemiptera: Cicadidae)Abstract}, year = {2019}, abstract = {

Cicadas probably experience mate recognition challenges as a result of the densities that may occur during adult emergence events, and in Okanagana, the most speciose genus of North American cicadas, high alpha diversities during protoperiodical emergences will exacerbate the mate recognition problem. Using 227 songs from 23 taxa, a linear plateau model regressed recognition potential, estimated from linear discriminant analysis, against song distance, revealing a critical song distance of 0.728 standard deviations in z-transformed song parameter space accompanied by a recognition of 91.6\%. Based on detailed examination of museum specimen localities, field observations and habitat, taxa were classified as sympatric or allopatric. Sympatric species were separated by song distances that were significantly greater than this critical distance. As expected for mate recognition characters, little within-species variance was observed in the songs of most species, and the relationship between increases in syllable rate and improved recognition was one of diminishing returns. For several taxa that sang with extreme syllable rates of high variance, a mate recognition \– sexual selection continuum is proposed. Along this continuum rapid rates simultaneously prevent mate recognition errors while signalling male quality to females.

}, keywords = {California, female preference, indicator trait, linear discriminant function, linear plateau analysis, Okanagana, receiver bias, sexual selection}, doi = {10.1093/biolinnean/blz132}, url = {https://academic.oup.com/biolinnean/advance-article/doi/10.1093/biolinnean/blz132/5602697}, author = {Chatfield-Taylor, Will and Jeffrey A. Cole} } @article {57388, title = {Opportunity for female choice in the wild is frequently curtailed by low male trait variation in Hyla versicolor}, year = {2019}, abstract = {

To understand the efficacy of female choice in driving the evolution of male displays, we need to not only characterize preferences but examine the opportunity for the expression of such preferences. Mate assessment by females should be constrained if the relative attractiveness of multiple displays is perceived as equal because trait differences between them are indistinguishable. This is expected to result in apparently arbitrary mate choice, and knowledge about the frequency of such mating patterns is crucial in predicting the strength of sexual selection. Here, we examine discrimination abilities of female Hyla versicolor in the context of actual male-male chorus variation. We found that roughly half of mating encounters in the wild do not provide the call variation required for the expression of female preferences (non-arbitrary choice). Interestingly, the trait for which female H. versicolor shows the strongest preference during playback trials (call duration) is not the trait whose difference will most often be detectable to females in the wild (call rate). Furthermore, we document individual variation in discrimination ability, with some females being able to discriminate multiple traits, while others only focus on one trait. This suggests that the relatively high estimate of arbitrary mating is not only due to females struggling to discriminate natural local variation overall but due to an abundance of individuals with limited discrimination abilities that require encounters with males that differ in the specific trait they will discriminate. Lastly, small trait differences between males do not arise from nearest neighbors plastically altering their calls to be more similar. These findings provide insights on the frequently observed mismatch between laboratory phonotaxis and actual mating success in the wild.

}, keywords = {acoustic communication, Female choice, mate preference, Random mating, sexual selection}, doi = {10.1007/s00265-019-2666-z}, url = {http://link.springer.com/10.1007/s00265-019-2666-z}, author = {Stratman, Kane D. and H{\"o}bel, Gerlinde} } @article {57346, title = {Evidence for differing trajectories of songs in urban and rural populations}, journal = {Behavioral Ecology}, year = {2019}, month = {Jul-08-2020}, abstract = {

Learned traits, such as foraging strategies and communication signals, can change over time via cultural evolution. Using historical recordings, we investigate the cultural evolution of birdsong over nearly a 50-year period. Specifically, we examine the parts of white-crowned sparrow (Zonotrichia leucophrys nuttalli) songs used for mate attraction and territorial defense. We compared historical (early 1970s) recordings with contemporary (mid-2010s) recordings from populations within and near San Francisco, CA and assessed the vocal performance of these songs. Because birds exposed to anthropogenic noise tend to sing at higher minimum frequencies with narrower frequency bandwidths, potentially reducing one measure of song performance, we hypothesized that other song features, such as syllable complexity, might be exaggerated, as an alternative means to display performance capabilities. We found that vocal performance increased between historical and contemporary songs, with a larger effect size for urban songs, and that syllable complexity, measured as the number of frequency modulations per syllable, was historically low for urban males but increased significantly in urban songs. We interpret these results as evidence for males increasing song complexity and trilled performance over time in urban habitats, despite performance constraints from urban noise, and suggest a new line of inquiry into how environments alter vocal performance over time.

}, keywords = {anthropogenic noise, birdsong, Cultural evolution, sexual selection, Urbanization, vocal performance}, issn = {1045-2249}, doi = {10.1093/beheco/arz142}, url = {https://academic.oup.com/beheco/advance-article/doi/10.1093/beheco/arz142/5551107}, author = {Moseley, Dana L and Jennifer N. Phillips and Derryberry, Elizabeth P and David A. Luther}, editor = {Candolin, Ulrika} } @article {53584, title = {Environmental constraints on size-dependent signaling affects mating and rival interactions}, journal = {Behavioral Ecology}, year = {2019}, month = {Mar-02-2020}, abstract = {

Advertisement signals can convey information about a sender\’s characteristics, such as body size. The reliability of signals, however, can be reduced when signal production is partially dependent on the environment. Here, we assess the effect of display-site properties on the production, attractiveness and honesty of sexual signals. We recorded male t\úngara frogs (Physalaemus pustulosus) while manipulating water levels in order to constrain calling. We found that water level affected male call properties in a size-dependent manner, with call amplitude being less affected in smaller males when forced to call in shallow water. Next, we tested how size-dependent and display-site-dependent signaling affected female choice and rival competition. Both males and females showed the strongest response to the call of a large male when he was calling at the deepest water levels. However, females showed no preference for large over small males when both were recorded in shallow water levels, or, depending on the call rate and timing of calls, even preferred small males. Likewise, males responded equally to large and small rivals recorded calling during shallow water level trials. Our experiments show that display-site properties can influence signal production and attractiveness in a size-dependent manner. These results can have important consequences for the evolution of signaling, as small males may be able to use their size to their advantage when selecting appropriate display sites and thereby outcompete large males.

}, keywords = {display site, honest signaling, Physalaemus pustulosus, production constraints, sexual selection}, issn = {1045-2249}, doi = {10.1093/beheco/arz009}, url = {https://academic.oup.com/beheco/advance-article/doi/10.1093/beheco/arz009/5320523}, author = {Smit, Judith A H and Loning, Hugo and Halfwerk, Wouter} } @article {53415, title = {Temperature alters multimodal signaling and mating success in an ectotherm}, journal = {Behavioral Ecology and Sociobiology}, volume = {72}, year = {2018}, month = {Jan-12-2018}, abstract = {

Temperature affects ectotherms in a variety of ways. These effects can be especially complex in sexual behaviors, as different sexes may be affected differently by temperature. We examined this in the jumping spider, Habronattus clypeatus. In this species, males court females using visual and vibratory signals. We tested whether key intersexual behaviors would change with temperature in similar, predictable ways across males and females. We first measured temperature and apparent activity of individuals across the day. We found that H. clypeatus are active across a wide range of temperatures (11\–56 \°C) and are most active at times of day when temperature ranges from 13 to 46 \°C. Next, we performed mating experiments across behaviorally relevant temperatures. Females were more likely to allow males to progress to later stages of courtship and had higher mating rates at higher temperatures. Male visual and vibratory courtship behaviors generally became faster, higher-pitched, and lower in amplitude at higher temperatures. This relationship between temperature and signal aspects attained a roughly curvilinear shape, with an asymptote around 40 \°C. Intriguingly, mating rates in the lab were highest at temperatures potentially above those during peak spider activity in the field. Our results suggest that temperature\’s effects on behavior are complex and can affect males and females differently. This work emphasizes that understanding temperature effects on mating is critical to understanding sexual selection patterns particularly in species which use complex signals.

}, keywords = {biotremology, communication, multimodal signals, Salticidae, sexual selection, Temperature, Thermal ecology, Vibratory communication}, issn = {0340-5443}, doi = {10.1007/s00265-018-2620-5}, url = {http://link.springer.com/10.1007/s00265-018-2620-5}, author = {Brandt, Erin E. and Kelley, J. Patrick and Elias, Damian O.} } @article {53414, title = {Behavioral and neural auditory thresholds in a frog}, journal = {Current Zoology}, year = {2018}, abstract = {

Vocalizations play a critical role in mate recognition and mate choice in a number of taxa, especially, but not limited to, orthopterans, frogs, and birds. But receivers can only recognize and prefer sounds that they can hear. Thus a fundamental question linking neurobiology and sexual selection asks\— what is the threshold for detecting acoustic sexual displays? In this study we use three methods to assess such thresholds in t\úngara frogs: behavioral responses, auditory brainstem responses, and multi-unit electrophysiological recordings from the midbrain. We show that thresholds are lowest for multi-unit recordings (ca. 45 dB SPL), and then for behavioral responses (ca. 61 dB SPL), with auditory brainstem responses exhibiting the highest thresholds (ca. 71 dB SPL). We discuss why these estimates differ and why, as with other studies, it is unlikely that they should be the same. Although all of these studies estimate thresholds they are not measuring the same thresholds; behavioral thresholds are based on signal salience while the two neural assays estimate physiological thresholds. All three estimates, however, make it clear that to have an appreciation for detection and salience of acoustic signals we must listen to those signals through the ears of the receivers.

}, keywords = {anurans, auditory brainstem responses, auditory thresholds, mate choice, Physalaemus pustulosus, sexual selection, signal recognition thresholds, t{\'u}ngara frogs, vocalizations}, author = {Ryan, C and Akre, Karin and Wilczynski, Walter and others} } @article {53376, title = {Convenience polyandry and the role of lone and reciprocal calls in a psyllid}, journal = {Animal Behaviour}, volume = {145}, year = {2018}, month = {Jan-11-2018}, pages = {1 - 10}, abstract = {

It is widely accepted that receptivity to mating may be asymmetrical between the sexes. While reproductive benefits for males are cumulative, females may not benefit equally from polyandry, especially in species where females can store sperm. Female psyllids (Hemiptera: Psylloidea) are reportedly polyandrous. However, the adaptive significance of this mating strategy has not been thoroughly investigated. Studies involving other insect species indicate that polyandry may be driven by benefits (direct or indirect) or by the need to minimize costs associated with male harassment. Drooping she-oak psyllids, Aacanthocnema dobsoni (Triozidae), use substrate-borne vibrations for mate attraction but they are not a prerequisite for mating. We suspected that polyandry in this species could be driven by male harassment because males exhibit indiscriminate mating behaviour (consistent with a scramble competition mating strategy), often mating with unresponsive (mated) females. We investigated relationships between calling, feeding and mating status to test whether females mate to minimize harassment by males and whether they gain any direct benefits from polyandry. We found that lone calls were commonly, but reciprocal calls were rarely followed by mating. As reciprocal calls should reflect female receptivity, copulations without them highlight the existence of sexual conflict over mating. Observations revealed that feeding females were less likely to resist mating than nonfeeding females. We did not find that females obtained any direct benefits from polyandry. Our results suggest that polyandry in this species may be a consequence of male harassment and that mated females, while feeding, may remate for convenience to minimize costs associated with stylet retraction/penetration and location of new feeding sites.

}, keywords = {economics of mating, feeding requirements, Psylloidea, reproductive success, sexual conflict, sexual selection}, issn = {00033472}, doi = {10.1016/j.anbehav.2018.09.001}, url = {https://linkinghub.elsevier.com/retrieve/pii/S0003347218302707https://api.elsevier.com/content/article/PII:S0003347218302707?httpAccept=text/xmlhttps://api.elsevier.com/content/article/PII:S0003347218302707?httpAccept=text/plain}, author = {Lubanga, U.K. and Peters, R.A. and Steinbauer, M.J.} } @article {52753, title = {The {\textquoteleft}hot male{\textquoteright} hypothesis: do female crickets prefer males with increased body temperature in mate choice scenarios?}, journal = {Animal Behaviour}, volume = {138}, year = {2018}, month = {Jan-04-2018}, pages = {75 - 84}, abstract = {

Insects have been extensively used as model systems to study mating preferences based on variation in acoustic signals. In many species, females perform phonotaxis towards attractive, long-range acoustic signals produced by males, whereas the final mating decision is based on an assessment of additional, multimodal, close-range cues. The production of acoustic signals is costly, because invested energy is inefficiently converted into acoustic power. Here, we investigated whether heat released as a by-product during song generation might serve as an additional cue during mate choice decisions. Males that broadcast highly energetic calling songs increased their thoracic temperature considerably above ambient temperatures. The use of this additional cue would turn the acoustic signal into an inherently bimodal one, indirectly indicating the quality of the sender. To test this hot male hypothesis, we performed trackball and Y-maze experiments with Anurogryllus muticus. For comparison, additional trackball experiments were conducted with Gryllus bimaculatus females. In all paradigms, females of both species showed no evidence of a preference for hot males and, therefore, we conclude that increases in thoracic temperature do not seem to play a role as a multimodal component in mate choice decisions in A. muticus.

}, keywords = {acoustic signals, Anurogryllus muticus, energy, Female choice, infrared thermography, male quality, multimodal communication, sexual selection, thermal cues, thoracic temperature increase}, issn = {00033472}, doi = {10.1016/j.anbehav.2018.02.007}, url = {http://linkinghub.elsevier.com/retrieve/pii/S0003347218300575}, author = {Erregger, Bettina and Hennig, R. Matthias} } @article {52579, title = {Mate choice intensifies motor signalling in Drosophila}, journal = {Animal Behaviour}, volume = {133}, year = {2017}, month = {Jan-11-2017}, pages = {169 - 187}, abstract = {

Mate choice has the potential to act on the evolution of motor performance via its direct influence on motor sexual signals. However, studies demonstrating this are rare. Here, we performed an in-depth analysis of Drosophila pseudoobscura courtship song rate, a motor signal under mate choice in this species, and analysed the response of this signal to sexual selection manipulation using experimental evolution. We show that manipulating the opportunity for sexual selection led to changes in song production rate and singing endurance, with males from the polyandrous populations producing faster song rates over longer time periods than males from monogamous populations. We also show that song rate was correlated with estimates of overall courtship vigour. Our results suggest that the action of mate choice on a motor signal has affected male motor performance displayed during courtship. We consider potential selective benefits associated with changes in motor performance, including condition- dependent signalling, and discuss the implications of these results for the study of motor signals un- der sexual selection.

}, keywords = {courtship song, Drosophila pseudoobscura, experimental evolution, interpulse interval, mate choice, motor performance, sexual selection}, issn = {00033472}, doi = {10.1016/j.anbehav.2017.09.014}, url = {http://linkinghub.elsevier.com/retrieve/pii/S0003347217303019}, author = {Debelle, Allan and Courtiol, Alexandre and Ritchie, Michael G. and Snook, Rhonda R.} } @article {52577, title = {Birdsong {\textquoteleft}performance{\textquoteright} studies: a sad commentary}, journal = {Animal Behaviour}, volume = {133}, year = {2017}, month = {Jan-11-2017}, pages = {209 - 210}, keywords = {birdsong, performance, sexual selection, vocal deviation}, issn = {00033472}, doi = {10.1016/j.anbehav.2017.09.019}, url = {http://linkinghub.elsevier.com/retrieve/pii/S0003347217303068}, author = {Kroodsma, Donald} } @article {52575, title = {Interactions between complex multisensory signal components result in unexpected mate choice responses}, journal = {Animal Behaviour}, volume = {134}, year = {2017}, month = {Jan-12-2017}, pages = {239 - 247}, abstract = {

Multimodal (multisensory) signalling is common in many species and often facilitates communication. How receivers integrate individual signal components of multisensory displays, especially with regard to variance in signal complexity, has received relatively little attention. In nature, male t\úngara frogs, Physalaemus pustulosus, produce multisensory courtship signals by vocalizing and presenting their inflating and deflating vocal sac as a visual cue. Males can produce a simple call (whine only) or a complex call (whine \þ one or more chucks). In a series of two-choice experiments, we tested female preferences for variation in acoustic call complexity and amplitude (unimodal signals). We then tested preferences for the same calls when a dynamic robotic frog was added to one call, generating a multi- modal stimulus. Females preferred a complex call to a simple call; when both calls contained at least one chuck, additional numbers of chucks did not further increase attractiveness. When calls contained zero or one chuck, the visual stimulus of the robofrog increased call attractiveness. When calls contained multiple chucks, however, the visual component failed to enhance call attractiveness. Females also preferred higher amplitude calls and the addition of the visual component to a lower amplitude call did not alter this preference. At relatively small amplitude differences, however, the visual signal increased overall discrimination between the calls. These results indicate that the visual signal component does not provide simple enhancement of call attractiveness. Instead, females integrate multisensory components in a nonlinear fashion. The resulting perception and behavioural response to complex signals probably evolved in response to animals that communicate in noisy environments.

}, keywords = {anurans, mate choice, multimodal signalling, nonlinear interactions, sexual selection, signal weighting, t{\'u}ngara frog, vocal sac}, issn = {00033472}, doi = {10.1016/j.anbehav.2016.07.005}, url = {http://linkinghub.elsevier.com/retrieve/pii/S000334721630121X}, author = {Stange, Nicole and Rachel A. Page and Michael J. Ryan and Taylor, Ryan C.} } @article {52571, title = {Complex signals and comparative mate assessment in wolf spiders: results from multimodal playback studies}, journal = {Animal Behaviour}, volume = {134}, year = {2017}, month = {Jan-12-2017}, pages = {283 - 299}, abstract = {

Complex signals of animals involve multiple sensory modes and contain multiple structural components, and teasing apart how these modes and components interact in receiver decision making is an experi- mental challenge. Females of many species have ordered preferences for increased size or expression of male indicator traits. However, studies also suggest other species may exhibit comparative evaluation of mates rather than absolute preference hierarchies. We examined mate assessment by female wolf spi- ders, Schizocosa ocreata, using digital playback of video and vibratory/seismic signals in preference and choice tests of male trait differences. In playback experiments, female wolf spiders showed ordered preferences for male condition indicating traits (leg tuft size, vibration signal amplitude) in both indi- vidual sensory modes and multimodal (combined) signals. Tests with single modes and multimodal signals showed that trait expression in either signal mode affects outcome of mate choice. Females exhibited transitive preferences, consistently choosing males with larger tuft size or higher amplitude vibration in no-choice and two-choice tests. Thus, female S. ocreata do not necessarily need to compare mates to exhibit preferences for particular traits. Choice tests with multimodal playback showed that females made predicted choices when male traits covaried positively, but in \‘cue-conflict\’ (negative trait covariance) choice tests, females showed a bias for visual signal trait expression (tuft size), displaying priority for visual signals over vibratory signals when in conflict. These studies demonstrate that under controlled experimental conditions, differences in behavioural responses to manipulation of digital video and vibration playback can provide valuable insights about recognition and interpretation of complex signals and their components.

}, keywords = {complex signals, Lycosidae, mate preference, multimodal communication, sexual selection, vibratory playback, video playback}, issn = {00033472}, doi = {10.1016/j.anbehav.2017.02.007}, url = {http://linkinghub.elsevier.com/retrieve/pii/S0003347217300441}, author = {Uetz, George W. and Stoffer, Brent and Lallo, Madeline M. and Clark, David L.} } @article {50521, title = {Inheritance of song and stridulatory peg number divergence between Chorthippus brunneus and C. jacobsi, two naturally hybridizing grasshopper species (Orthoptera: Acrididae)}, journal = {Journal of Evolutionary Biology}, volume = {18}, year = {2005}, month = {Jan-05-2005}, pages = {703 - 712}, abstract = {

Knowledge of the genetic basis of divergence in mating signal characters that contribute to reproductive isolation is critical to understanding speciation. Here, we describe a semi-automated system for characterizing grasshopper acoustic signals. We used this system to study the genetic basis of divergence in three male calling song components [echeme (EL), syllable (SL) and phrase (PL) lengths] between Chorthippus brunneus and C. jacobsi , two species of grasshoppers that hybridize in northern Spain. We also studied the number of pegs in the stridulatory file. For all characters, additive effects accounted for most of the genetic differentiation between species. However, the three song components also showed small but significant epistatic effects. No sex linkage was detected. Wright\–Castle\–Lande estimates of the minimum numbers of genetic factors underlying song and peg number divergence were low: peg number ( n e \¼ 5.87 \± 5.84), SL ( n e \¼ 2.37 \± 4.79) and PL ( n e \¼ 0.87 \± 0.86). On the other hand, EL appeared to be controlled by many genes. These results suggest that divergence in SL and PL might be driven by sexual selection whereas EL might not be under selection. This is consistent with experimental results on female song preference in related species. However, the fact that few factors appear to underlie the differences in peg number is surprising. Peg number is not closely related to song characteristics. It often varies between closely related grasshopper species and it has been assumed to be a neutral character. The biometrical approaches used here tend to underestimate the number of factors influencing a trait but provide valuable background for subsequent quantitative trait loci analyses.

}, keywords = {additive effects, dominance effects, effective number of factors, epistasis, mosaic hybrid zones, quantitative trait loci, sexual selection, wavelet transformation}, doi = {10.1111/jeb.2005.18.issue-310.1111/j.1420-9101.2004.00838.x}, url = {http://blackwell-synergy.com/doi/abs/10.1111/jeb.2005.18.issue-3}, author = {C. I. Sadamando and S. Miyaguchi and H. Tatsuta and H. Kishino and J. R. Bridle and R. K. Butlin} } @article {50500, title = {Voices of Africa: acoustic predictors of human male vocal attractiveness}, journal = {Animal Behaviour}, volume = {127}, year = {2017}, month = {Jan-05-2017}, pages = {205 - 211}, abstract = {

Robust evidence shows that voice quality affects various social interactions, including mate preferences. Previous research found that male voices perceived as attractive are characterized by low voice pitch, lower or sexually typical formants and relatively high breathiness. These features tend to be seen as markers of an individual\&$\#$39;s quality as a potential mate. Although there are considerable differences between languages in vocal parameters that could influence the perceived attractiveness, the above-mentioned findings rely on research based mainly on participants from European or North American countries. In our study, we therefore tested the main acoustic predictors of vocal attractiveness using two male samples from Cameroon and Namibia. Standardized vocal recordings were then assessed for vocal attractiveness by a panel of female raters from the Czech Republic. Our results show that in the Cameroonian voices, fundamental frequency was strongly negatively associated with perceived vocal attractiveness. In the Namibian sample, however, it was not the fundamental frequency but lower mean formants and harmonics-to-noise ratio that were negatively associated with vocal attractiveness. This pattern may be partly attributed to differences in morphological characteristics such as the body mass index, indicating variation across individual populations.

}, keywords = {attractiveness, body mass index, formant, fundamental frequency, human, male, sexual selection, undernutrition, voice, y harmonics-to-noise ratio}, issn = {00033472}, doi = {10.1016/j.anbehav.2017.03.014}, url = {http://linkinghub.elsevier.com/retrieve/pii/S0003347217300866}, author = {{\v S}ebesta, Pavel and Kleisner, Karel and Ture{\v c}ek, Petr and Ko{\v c}nar, Tom{\'a}{\v s} and Akoko, Robert Mbe and T{\v r}ebick{\'y}, V{\'\i}t and Havl{\'\i}{\v c}ek, Jan} } @article {50484, title = {Divergent mechanisms of acoustic mate recognition between closely related field cricket species ( Teleogryllus spp.)}, journal = {Animal Behaviour}, volume = {130}, year = {2017}, month = {Jan-08-2017}, pages = {17 - 25}, abstract = {

Effective recognition of conspeci fi c mating signals reduces the risk of maladaptive hybridization. Dis- secting the signal recognition algorithms that underlie preferences is a useful approach for testing whether closely related taxa evaluate the same or different signal features to achieve mate recognition. Such data provide information about potential constraints and targets of selection during evolutionary divergence. Using a series of mate choice trials, we tested whether closely related, but genetically and phenotypically divergent, fi eld cricket species ( Teleogryllus oceanicus and Teleogryllus commodus ) use shared or distinct recognition algorithms when evaluating acoustic male calling songs. These species overlap in sympatry, show premating isolation based on female discrimination of male calling songs, yet are capable of producing hybrid offspring. Unexpectedly, female selectivity for features of male song differed between the two species. We found that the two species use a combination of shared and unique signal fi ltering mechanisms, and we characterized how information about male carrier frequency, pulse rate and temporal patterning is integrated to achieve song recognition in each species. These results illustrate how comparatively few, simple modi fi cations in key components of signal recognition algo- rithms can lead to striking interspeci fi c discrimination between closely related taxa, despite apparent signal complexity. The fi nding that some steps during signal recognition and fi ltering are shared between the species, while others differ, can help to identify behavioural traits targeted by selection during evolutionary divergence

}, keywords = {acoustic communication, divergence, female preference, mate recognition, reproductive isolation, sexual selection, speciation, Teleogryllus}, issn = {00033472}, doi = {10.1016/j.anbehav.2017.06.007}, url = {http://linkinghub.elsevier.com/retrieve/pii/S0003347217301823}, author = {Nathan W. Bailey and R. Matthias Hennig} } @article {47779, title = {Effects of juvenile and adult condition on long-distance call components in the Jamaican field cricket, Gryllus assimilis}, journal = {Animal Behaviour}, volume = {81}, year = {2011}, month = {Jan-01-2011}, pages = {135 - 144}, abstract = {

Complex signals may arise through either content- or efficacy-based selection. Content-based signals are thought to evolve because of the information content they provide to the receiver. Such signals may function as multiple messages, each relaying different information or types of information. For example, some signals or signal components may indicate different aspects of condition, or condition at different life stages (quality signals), while others relay information on signaller location, or function in species recognition. Or they may act as redundant signals of overall condition, or as backup signals of the same aspect of condition. Efficacy-based signals are proposed to evolve because of the way in which they influence the production, transmission, reception or processing of the signal. We manipulated juvenile and adult condition in male Jamaican field crickets, Gryllus assimilis, to test whether changes in components of the male\’s long-distance acoustic mate attraction signal were consistent with content- or efficacy-based selection. Several call components exhibited condition-dependence, and may be under content-based selection. Interpulse duration, pulse rate and chirp duration appeared to honestly signal juvenile condition, while dominant frequency appeared to signal adult condition. Thus, these signal components appeared to be acting as multiple messages of quality. Pulse number, interchirp duration and chirp rate were highly stereotyped and probably function in species recognition. Call number increased with decreasing condition and was likely under efficacy-based selection. No call components appeared to have the potential to act as redundant signals.

}, keywords = {acoustic signal, complex signal, condition-dependence, content, efficacy, Field cricket, multiple messages, multiple signals, redundant signal, sexual selection}, issn = {00033472}, doi = {10.1016/j.anbehav.2010.09.024}, url = {http://linkinghub.elsevier.com/retrieve/pii/S0003347210003933}, author = {Whattam, Emily M. and Bertram, Susan M.} } @article {47593, title = {Male{\textendash}male courtship behaviour, not relatedness, affects the intensity of contest competition in the field cricket}, journal = {Animal Behaviour}, volume = {126}, year = {2017}, month = {Jan-04-2017}, pages = {217 - 220}, abstract = {

Males often compete intensely against rival males because access to females is a major factor contrib- uting to their reproductive success. However, there is controversy over whether maleemale competition is weakened when rival males are related, with reduced aggressiveness leading to inclusive fitness benefits. Furthermore, same-sex sexual behaviour is also expected to mitigate maleemale contests. Here, I examined how relatedness, developmental familiarity (i.e. males reared in the same container or not) and same sex sexual behaviour affect the intensity of maleemale competition in wild-caught field crickets, Teleogryllus occipitalis. Relatedness and familiarity had no significant effect on the intensity of maleemale contest behaviour. However, same-sex sexual behaviour did weaken maleemale competi- tion. In conclusion, my results indicate that same-sex sexual behaviour in this cricket has adaptive sig- nificance by mitigating risky maleemale contest behaviour.

}, keywords = {intrasexual competition, kin selection, same-sex sexual behaviour, sexual selection, Teleogryllus occipitalis}, issn = {00033472}, doi = {10.1016/j.anbehav.2017.02.009}, url = {http://linkinghub.elsevier.com/retrieve/pii/S0003347217300465}, author = {Kuriwada, Takashi} } @article {20904, title = {Evolutionary diversification of the auditory organ sensilla in Neoconocephalus katydids (Orthoptera: Tettigoniidae) correlates with acoustic signal diversification over phylogenetic relatedness and life history}, journal = {Journal of Evolutionary Biology}, year = {2017}, month = {Jan-03-2017}, abstract = {

Neoconocephalus tettigoniids are a model for the evolution of acoustic signals as male calls have diversified in temporal structure during the radiation of the genus. Tettigoniidae have hearing organs in the forelegs with species-specific numbers of auditory sensilla in a linear crista acustica. We investigated changes of the hearing organs during an evolutionary radiation with divergence of intraspecific acoustic signals. We compared the neuroanatomy of the crista acustica from 9 Neoconocephalus species with different temporal call features, life histories, and from different phylogenetic positions. Average numbers of auditory sensilla were species-specific, ranging between 32\–35 sensilla. It is likely under sexual selection for detection of male calls and natural selection for detection of bat calls. We found statistically significant differences in sensillum numbers among species, but no relationship of crista acustica length or sensillum number with phylogenetic position or life history. Statistically significant correlations existed with call patterns: species with slow pulse rates had significantly higher numbers of auditory sensilla and a longer crista acustica. Further, species with a derived double-pulsed calls had longer cristae, and continuous callers had a higher number of auditory sensilla. Correlations with crista length were stronger than with the number of auditory sensilla. The hearing organs show considerable diversity between species despite their recent divergence and morphological and ecological similarities. Thus, they have the potential to respond to various selective pressures, including divergence of temporal and spectral signal properties. Phylogenetic constraints are unlikely to limit the evolutionary change of the auditory systems.

}, keywords = {hearing organ, insects, radiation, sensory evolution, sexual selection, signal evolution, tympanal organ}, doi = {10.1111/jeb.13066}, url = {http://doi.wiley.com/10.1111/jeb.13066}, author = {Strau{\ss}, Johannes and Alt, Joscha A. and Ekschmitt, Klemens and Schul, Johannes and Lakes-Harlan, Reinhard} } @article {16466, title = {Acoustic preference functions and song variability in the Hawaiian cricket Laupala cerasina}, journal = {Proceedings of the Royal Society B: Biological Sciences}, volume = {267}, year = {2000}, month = {Oct-03-2001}, pages = {577 - 584}, abstract = {

Female preference functions for di\¡erent sexual traits can di\¡er signi\¢cantly, from {\textquoteleft}unimodal\’ to {\textquoteleft}open ended\’. Through the study of acoustic communication in anurans, several studies have reported an association between static (stereotyped) traits versus dynamic (variable) traits and preference function shape (unimodal versus open ended, respectively). Observing a similar pattern in a phylogenetically independent group would suggest that deterministic forces have caused a relationship between signal variability and preference function shape in acoustic signalling systems. We examined this phenomenon in crickets, another animal characterized by intersexual acoustic communication. We measured the within- male variability for three acoustic features of the male calling song in Laupala cerasina and the corresponding shape of the female preference function for each of these features. We o\¡er support for the generalization that open-ended preference functions correspond to relatively dynamic courtship traits and unimodal preference functions correspond to relatively static courtship traits. We discuss the evolutionary signi\¢cance of these \¢ndings in the context of the natural history of the Laupala species radiation.

}, keywords = {acoustic communication, crickets, mate recognition, preference, sexual selection, song}, issn = {0962-8452}, doi = {10.1098/rspb.2000.1040}, url = {http://rspb.royalsocietypublishing.org/cgi/doi/10.1098/rspb.2000.1040}, author = {Shaw, K. L. and Herlihy, D. P.} }