01933nas a2200145 4500008004100000245013200041210006900173300001400242490000700256520141400263100002001677700002101697700002801718856004101746 2010 eng d00aRisk trading in mating behavior: forgoing anti-predatorresponses reduces the likelihood of missing terminalmating opportunities0 aRisk trading in mating behavior forgoing antipredatorresponses r a1485-14940 v643 a

Life history theory predicts that organisms make certain adjustments to their current and future reproductive effort such that fitness is maximized. Moreover, these adjustments may be fine tuned in response to risks of attack by natural enemies. Thus, we may predict that as an organism ages it will accept increasing levels of exposure to predators during mating activities, effectively trading the risk of losing terminal mating opportunities for the risk of predation. We tested this prediction in an acoustic moth, Achroia grisella, in which females orient toward and evaluate males based on their ultrasonic calling song, and both sexes may be vulnerable to predation by insectivorous bats while in flight as well as on the substrate. In the latter situation, singing males and orienting females show silence and arrestment responses, respectively, when presented with synthetic bat echolocation signals broadcast above a threshold amplitude. We found that both males and females become less sensitive to these broadcasts over the course of their brief reproductive periods, 7 and 5 days, respectively. Over the same periods, sensitivity to male song in both males and females remains constant, and relatively little senescence in sexual behavior is observed. These results support the risk trading hypothesis, and they indicate that life history principles may apply over a very short lifespan.

1 aLafaille, Marie1 aBimbard, Gaëlle1 aGreenfield, Michael, D. uhttps://bio.acousti.ca/fi/node/5845602103nas a2200157 4500008004100000022001400041245009100055210006900146260001600215490000700231520158800238100001901826700002401845700002101869856005501890 2019 eng d a0340-544300aClarifying and expanding the social complexity hypothesis for communicative complexity0 aClarifying and expanding the social complexity hypothesis for co cJan-01-20190 v733 a

Variation in communicative complexity has been conceptually and empirically attributed to social complexity, with animals living in more complex social environments exhibiting more signals and/or more complex signals than animals living in simpler social environments. As compelling as studies highlighting a link between social and communicative variables are, this hypothesis remains challenged by operational problems, contrasting results, and several weaknesses of the associated tests. Specifically, how to best operationalize social and communicative complexity remains debated; alternative hypotheses, such as the role of a species’ ecology, morphology, or phylogenetic history, have been neglected; and the actual ways in which variation in signaling is directly affected by social factors remain largely unexplored. In this review, we address these three issues and propose an extension of the “social complexity hypothesis for communicative complexity” that resolves and acknowledges the above factors. We specifically argue for integrating the inherently multimodal nature of communication into a more comprehensive framework and for acknowledging the social context of derived signals and the potential of audience effects. By doing so, we believe it will be possible to generate more accurate predictions about which specific social parameters may be responsible for selection on new or more complex signals, as well as to uncover potential adaptive functions that are not necessarily apparent from studying communication in only one modality.

1 aPeckre, Louise1 aKappeler, Peter, M.1 aFichtel, Claudia uhttp://link.springer.com/10.1007/s00265-018-2605-402027nas a2200145 4500008004100000022001400041245007900055210006900134260001600203490000700219520155800226100002101784700002101805856005501826 2018 eng d a0340-544300aConspecific challenges provoke female canyon wrens to sing but not to duet0 aConspecific challenges provoke female canyon wrens to sing but n cJan-12-20180 v723 a

Song by female birds is rare in some species, particularly at north-temperate latitudes. Nevertheless, female song can carry important signal content and may be used in functional ways, both when sung solo and when combined into partner duets. Evidence supports the idea that duets reflect elevated threat levels because they indicate partner cooperation, but this comes from species with frequent female song and duetting. Here we asked the following questions about infrequently given female song in canyon wrens (Catherpes mexicanus) in Western North America. Do female birds use song in a context that implies functional significance? Do canyon wren mates combine their songs to form duets? Are duets a more threatening signal than non- overlapping dual-sex solo songs? To address these questions, we challenged canyon wrens with paired simulated intruders singing alternating solo songs or duets formed by overlapping male and female songs with consistent timing. Results indicated that female canyon wrens approached and sang in response to conspecific song playback as quickly as males did and increased their song rates significantly. Partners did not overlap their songs to create duets more often than expected by chance, and neither sex responded more strongly to duets than to solo songs. Outcomes match the prediction that duets only carry different signal content from solo song in species that frequently duet, and suggest that canyon wren female song is highly functional despite being rarely used outside of contest situations.

1 aHathcock, T., J.1 aBenedict, Lauryn uhttp://link.springer.com/10.1007/s00265-018-2625-002382nas a2200253 4500008004100000022001400041245007900055210006900134260001600203490000700219520162600226653001701852653001801869653002301887653001501910653002101925653001601946653002001962653002801982100002102010700002002031700002202051856005502073 2018 eng d a0340-544300aTemperature alters multimodal signaling and mating success in an ectotherm0 aTemperature alters multimodal signaling and mating success in an cJan-12-20180 v723 a

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.

10abiotremology10acommunication10amultimodal signals10aSalticidae10asexual selection10aTemperature10aThermal ecology10aVibratory communication1 aBrandt, Erin, E.1 aKelley, Patrick1 aElias, Damian, O. uhttp://link.springer.com/10.1007/s00265-018-2620-502307nas a2200241 4500008004100000022001400041245009600055210006900151260001600220490000700236520154300243653002201786653001901808653002201827653002401849653001901873100002601892700002501918700002601943700002401969700001701993856005502010 2018 eng d a0340-544300aAge and social affinity effects on contact call interactions in free-ranging spider monkeys0 aAge and social affinity effects on contact call interactions in  cJan-12-20180 v723 a

Nonhuman primates’ vocal repertoire has shown little plasticity, with immatures producing adult-like acoustic structures. Yet, the use of different call types shows a degree of socially dependent flexibility during development. In several nonhuman primate species, group members exchange contact calls respecting a set of social and temporal rules that may be learned (e.g., overlap avoidance, turn-taking, social selection of interacting partners, and call type matching). Here, we study the use of contact calls in free-living adult and immature (old and young) spider monkeys (Ateles geoffroyi). We focused our study in two contact call types of the species’ repertoire: whinnies and high-whinnies. Our results suggest that individuals in all age classes produced both call types, with immatures producing less frequently the whinny call type. Immature individuals exchanged calls less often than adults, although their contribution increased with age. Conversely, mature individuals regulated their emissions by (1) exchanging more calls with their preferred affiliative partner and (2) matching the call type, while immatures did not. Our results show that contact call usage changes during development and suggest that adult rules might be learned. We argue that call matching is a “conversational rule” that young individuals acquire with apparent call-type-dependent variations during development. Our findings support the idea that social factors influence vocal development in nonhuman primates.

10aAcoustic matching10aCall exchanges10aNew World monkeys10avocal communication10avocal learning1 aBriseno-Jaramillo, M.1 aRamos-Fernández, G.1 aPalacios-Romo, T., M.1 aSosa-López, J., R.1 aLemasson, A. uhttp://link.springer.com/10.1007/s00265-018-2615-201655nas a2200205 4500008004100000022001400041245007300055210006900128260001600197300001200213490000700225520104800232653002201280653002001302653001901322653002001341653001901361100002101380856004801401 1986 eng d a0340-544300aFemale preferences for male calling bout duration in a field cricket0 aFemale preferences for male calling bout duration in a field cri cJan-06-1986 a73 - 770 v193 a

The calls of male field crickets attract sexually receptive females. In Gryllus integer, males differ from one another in their durations of uninterrupted calling (calling bout lengths). Tape recordings of the calls of 50 wild-caught males revealed that 14 males spent most of their calling time in short bouts (Fig. 1A), 18 in both short and long bouts (Fig. 1B), and 18 in long bouts (Fig. 1C). Re-recordings of 32 males after 3 weeks showed that calling bout lengths of individual males are stable with time (age) (Fig. 2). Three phonotaxis experiments investigated whether calling bout lengths of males affect female preferences. They demonstrated that (1) females can discriminate among conspecific males on the basis of calls alone; (2) females are preferentially attracted to males with long calling bout lengths; and (3) calling bout length is the specific factor responsible for preferential attraction. These results precisely identify a criterion that females use to discriminate among potential mates of their own species.

10afemale preference10aIndividual Male10aPotential Mate10aSpecific Factor10aTape Recording1 aHedrick, Ann, V. uhttp://link.springer.com/10.1007/BF0030384502965nas a2200241 4500008004100000245011800041210006900159300001400228490000600242520224000248653001602488653001502504653002402519653001202543653002002555653001802575653001702593653002002610653001202630653001902642100002102661856004102682 1981 eng d00aMale spacing and the influence of female courtship behaviour in the bladder cicada, Cystosoma saundersii Westwood0 aMale spacing and the influence of female courtship behaviour in  a269–2760 v93 a

1. Experimental choruses of males of Cystosoma saundersii with manipulated densities -12 times that usually found in bushes of the same size were set up and compared with choruses with natural densities of males. Greater numbers of both males and females were attracted to the louder, denser choruses.

2. There were higher rates of dispersal away from and movements within the experimental choruses than those found at natural densities. This indicated some form of repulsion occurring between males in close proximity.

3. Playback experiments to calling males in the field showed that males would stop singing and move away in response to high intensities of a conspecific calling song. The intensities eliciting this reaction cor- responded to a conspecific male singing at separations of less than or equal to 0.5 m. Aggression between males or aggressive songs have not been observed.

4. Females fly in to the chorus and alight generally within 0.5 m of the male of their choice. They then produce a pheromone which they disperse by wing-flicking. The rate of wing-flicking was used as a quan- titative measure of the willingness of a female to mate.

5. Twice as many females were attracted to higher densities of males than to natural densities. However, in the experimental situation, the probability of an attracted female actually mating was half that occur- ring in natural densities. This appeared to be due to an inhibition of the female wing-flicking behaviour.

6. Playback experiments showed that females will respond by wing-flicking to a male only when his song is at least 9 dB louder than that of his nearest neighbour (when the sound pressure levels of the sources are measured separately at the position of the female). Using this figure as a threshold, volumes in which females would respond were calculated for males with a series of nearest-neighbour distances. At the average separation found between males sharing bushes in the field, the volume in which a female would respond covered most of the volume in which a female is likely to land. Thus, the discriminating capabilities of the female were shown to govern the minimum separation occurring between males.

10aAggregation10aamphibians10aanimal vocalization10aCicadas10aInsect behavior10aInsect sounds10aLoudspeakers10amating behavior10aSinging10aSound pressure1 aDoolan, Jane, M. uhttps://bio.acousti.ca/fi/node/5312302180nas a2200157 4500008004100000022001400041245010400055210006900159260001600228300001400244490000600258520166800264100002501932700001701957856004801974 1980 eng d a0340-544300aSound production in the cockroach, Gromphadorhina portentosa: evidence for communication by hissing0 aSound production in the cockroach Gromphadorhina portentosa evid cJan-03-1980 a305 - 3140 v63 a

1. Sound production of the giant Madagascar cockroach, Gromphadorhina portentosa, was examined by behavioral and acoustical methods in order to determine the functions of the hisses produced by this species.

2. Gromphadorhina is able to produce audible hisses from a pair of modified spiracles. Adult males hiss in three social contexts: during aggressive encounters, during courtship (when two types of hisses are discernable), and during copulation. Adults and nymphs of both sexes also hiss when disturbed (Figs 2 and 3).

3. There are reliable differences among hisses emitted in these social contexts which depend on several features: the shape of the amplitude envelope (Fig. 4), the relative loudness (Table 1), and the temporal characteristics both of single hisses and of hiss trains (Table 1 and Fig. 4).

4. In both courtship and aggression, hissing accompanies characteristic, stereotyped behavior patterns (Figs. 5 and 7); during aggressive encounters between males, hissing is predictive of winning (Fig. 6).

5. Males which have been silenced by occlusion of the specialized spiracles carry on apparently normal courtship, but they are unsuccessful in copulating due to a lack of receptive behavior by the female (Fig. 8).

6. Playback of recorded courtship hisses during courtship of females by silenced males leads to receptive behavior by females, and to normal rates of copulation (Fig. 8).

7. Our evidence supports the hypothesis that G. portentosa has evolved a system of communication in which hisses serve as auditory social signals.

1 aNelson, Margaret, C.1 aFraser, Jean uhttp://link.springer.com/10.1007/BF0029277302087nas a2200181 4500008004100000022001400041245012600055210006900181260001600250490000700266520148400273653001601757653001801773653002701791653001501818100001701833856005501850 2017 eng d a0340-544300aComponents of reproductive isolation between the closely related grasshopper species Chorthippus biguttulus and C. mollis0 aComponents of reproductive isolation between the closely related cJan-04-20170 v713 a

The formation and maintenance of species in nature is accomplished by the evolution of reproductive isolating mechanisms. To understand patterns of speciation and coexistence between species, it is crucial to obtain a complete synopsis of reproductive isolating barriers. We identified multiple reproductive isolation barriers between two closely related species, Chorthippus biguttulus and Chorthippus mollis, and quantified their respective contributions to isolation. To this end, we produced hybrids and backcrosses in the laboratory to examine reproductive isolation at multiple stages in the life history. The prezygotic barriers, based on chemical and acoustic cues, are currently the strongest impediments to gene flow between C. biguttulus and C. mollis. This indicates an important role for sexual selection in the maintenance of species isolation. However, extrinsic and intrinsic postzygotic isolation barriers also contributed to reproductive isolation. The virtual sterility of F1 hybrid males was based on both the dysfunctionality of their testes and intermediate behavioral mating traits (behavioral sterility). This study demonstrates that a cascade of reproductive isolating mechanisms reduces the gene flow between C. biguttulus and C. mollis. Our results further demonstrate that the courtship display in these species consists of multimodal signals and indicates a key role of chemical cues in reproductive isolation and speciation in grasshoppers.

10aChorthippus10ahybridization10areproductive isolation10aspeciation1 aFinck, Jonas uhttp://link.springer.com/10.1007/s00265-017-2295-301860nas a2200157 4500008004100000022001400041245012800055210006900183260001600252490000700268520131300275100001801588700002601606700002201632856004801654 1990 eng d a0340-544300aThe adaptive significance of acoustic spacing in male bushcrickets Tettigonia viridissima: a perturbation experiment0 aadaptive significance of acoustic spacing in male bushcrickets i cJan-01-19900 v263 a

A perturbation experiment was carried out in which the spacing between singing male bushcrickets, Tettigonia viridissima, was artificially manipulated. The experiment entailed releasing virgin females into an area in which caged males were either spaced evenly or in which a proportion of the males were clumped. There was large variation among males in the proportion of time spent singing (range 39–91% of total singing time). Singing activity was correlated with male body weight, but was not influenced by male spacing. Out of a total of 108 females released during the experiment, the majority (N=90) moved from their release points onto the cage of one of the closest singing males. More distant signalers sometimes attracted females when one of the closest males did not sing, or sang very little, during the period in which females were moving. When clumped, males were less successful in attracting females than when regularly spaced within the experimental area. Therefore, within a homogeneous habitat in which females are randomly distributed, male mating success will be maximized when males space out as far as possible from their competitors. As predicted, a regular dispersion of signaling males is the pattern observed in the preferred microhabitats of this species in nature.

1 aArak, Anthony1 aEiriksson, Thorleifur1 aRadesäter, Tommy uhttp://link.springer.com/10.1007/BF0017401901830nas a2200205 4500008004100000022001400041245010700055210006900162260001600231300001600247490000700263520117500270100002201445700002001467700002101487700002201508700002101530700001801551856005501569 2013 eng d a0340-544300aMultimodal signaling in the Small Torrent Frog (Micrixalus saxicola) in a complex acoustic environment0 aMultimodal signaling in the Small Torrent Frog Micrixalus saxico cJan-09-2013 a1449 - 14560 v673 a

Many animals use multimodal (both visual and acoustic) components in courtship signals. The acoustic communication of anuran amphibians can be masked by the presence of environmental background noise, and multimodal displays may enhance receiver detection in complex acoustic environments. In the present study, we measured sound pressure levels of concurrently calling males of the Small Torrent Frog (Micrixalus saxicola) and used acoustic playbacks and an inflatable balloon mimicking a vocal sac to investigate male responses to controlled unimodal (acoustic) and multimodal (acoustic and visual) dynamic stimuli in the frogs' natural habitat. Our results suggest that abiotic noise of the stream does not constrain signal detection, but males are faced with acoustic interference and masking from conspecific chorus noise. Multimodal stimuli elicited greater response from males and triggered significantly more visual signal responses than unimodal stimuli. We suggest that the vocal sac acts as a visual cue and improves detection and discrimination of acoustic signals by making them more salient to receivers amidst complex biotic background noise.

1 aPreininger, Doris1 aBoeckle, Markus1 aFreudmann, Anita1 aStarnberger, Iris1 aSztatecsny, Marc1 aHödl, Walter uhttp://link.springer.com/10.1007/s00265-013-1489-6