The Wheat dwarf virus, the causal agent of the wheat dwarf disease, is transmitted by leafhoppers from the genus Psammotettix and currently the main protection strategy is based on the use of ...insecticide treatments. Sustainable management strategies for insect vectors should include methods that are targeted to disrupt reproductive behavior and here we investigated the mating behavior of Psammotettix alineus (Dahlbom 1850) in order to determine the role of vibrational signals in intra‐specific communication and pair formation. Both genders spontaneously emit species‐ and sex‐specific calling songs that consisted of regularly repeated pulse trains and differ primarily in pulse train duration and pulse repetition time. Females preferred the conspecific male calling song. After a coordinated exchange of pulse trains, the male approached the stationary female. During the close range courtship and also immediately prior to copulatory attempts distinct male vibrational signals associated with wing flapping and wing vibrations were recorded from the substrate. In the presence of a receptive female, competing males emitted vibrational signals most likely aimed to interfere with male‐female interaction. Mated females regained sexual receptivity after they laid eggs. Although results suggest that the viruliferous status of insects may have an effect on vibrational songs, our current results did not reveal a significant effect of virus on leafhopper performance in mating behavior. However, this study also suggests, that detailed understanding of plant–vector–virus interactions relevant for vector mating behavior is essential for trying new approaches in developing future control practices against plant viruses transmitted by insect vectors.
This study examines the rate of female answers to conspecific versus heterospecific male vibratory calls in three, closely related stonefly species: Zwicknia bifrons, Z. acuta, and Z. rupprechti. In ...a previous study those three species were recognized on the basis of their distinct male drumming calls along with differences in genital morphology and genetic divergence. During this study no‐choice playback experiments using original male call samples from each species were performed, and the answer rate of females to conspecific and heterospecific signal variants was measured. Mixed effect logistic regression models were used to test if male call species identity had a statistically significant effect on female answer probability. Females answered conspecific male calls with significantly higher probability than heterospecific calls in all the three examined species, suggesting that the divergence of vibrational communication can be an important component of the prezygotic isolation between them. Low, but well detectable responsiveness to heterospecific calls was observable between Z. bifrons and Z. acuta, the two species closest to each other regarding mitochondrial genetic divergence and male call pattern similarity. Thus, our results are most congruent with a tight, gradual coevolution of male calls and female preferences.
Unintended receivers can be an important source of selection on social signals. Vibrational social signals are produced by diverse taxa, but most work on eavesdropping on social communication has ...focused on airborne signals. Few studies have examined whether predators and parasitoids exploit vibrational social signals, and whether vibrational communication systems have features to reduce apparency to unintended receivers. For a subsocial insect species (Hemiptera: Membracidae: Platycotis vittata), we first used a field playback experiment to show that offspring vibrational signals evoke maternal defense, and that maternal signals can inhibit offspring signaling. We next evaluated two potential benefits of inhibiting offspring signaling. We tested whether such inhibition increases the accuracy of offspring signals, as it does in a closely related species. We also tested whether by inhibiting offspring signals, mothers reduce the risk of attracting eavesdropping predators. Using playback experiments, we found that a vibrationally-sensitive predator attends to offspring but not maternal signals. In contrast, we found no evidence that inhibition increases the accuracy of offspring signals. Because predator eavesdropping is a likely cost of social communication for vibrationally signaling animals, we suggest that mechanisms to reduce apparency of such social signals may be common.
Scaphoideus titanus Ball (Hemiptera: Cicadellidae: Deltocephalinae) is the vector of the grapevine disease Flavescence dorée. In S. titanus the male-female duet (MFD), based on species-specific ...vibrational signals, is essential for successful copulation. The female reply within a duet is a single pulse that is coupled with the male pulse with constant latency. It has been shown that a rival male can interrupt an existing duet by emitting disruptive noise signals. We tested whether the reproductive behaviour of S. titanus can be disrupted by the playback of intra-specific and synthesized vibrational signals. Tested males responded to the playback of an MFD with typical rivalry behaviour. Such behaviour includes silent search for a duetting female (satellite behaviour) and/or emission of disruptive signals. These signals were emitted either after exchange of male-female pulses or after two male pulses coupled by latency corresponding to the female response window. The onset of male disruptive signals overlapped with a female pulse. We suggest that the intruder's disruptive signals can mask the female reply and confuse courting males. Playback of disruptive vibrational signals reduced the level of male calling and interrupted an established MFD that consequently resulted in a significantly reduced number of copulations. These results indicate that the vibrational communication channel is open to interference either from abiotic environmental noise or from signals produced by sexual competitors or heterospecifics. The present study also suggests that a detailed understanding of leafhopper behaviour is essential for trying new approaches in the development of more environmentally friendly control practices.
A mismatch in synchrony between male and female gamete release in external fertilizers can result in reduced or failed fertilization, sperm competition, and reduced paternity. In Arctic charr ...(Salvelinus alpinus), males can adopt either a guard or sneak tactic resulting in both pre‐ and postcopulatory competition between males with alternative reproduction tactics. Here, spawning behavior of free‐living Arctic charr was video‐recorded, and their reproductive behavior was analyzed. From evaluating 157 spawning events, we observed that females mainly spawned with a guarding male and that the female and the guarding male synchronized timing of gamete release under sperm competition. Although sneakers spawned with higher synchrony than the guarding male in single‐male spawning events, the average sneaker released his milt less synchronized with the female than the guarding male under sperm competition. Approximately 50% of the recorded spawning events occurred under sperm competition, where each event included an average of 2.7 males. Additionally, sneakers were more exposed to sperm competition than guarding males. An influx of males, in close proximity to the female, occurred during the behavioral sequences leading up to egg release, but this influx seemed not dependent on egg release, suggesting that something else than gonadal product attracts sneaker males to the spawning female. Just before and during the actual release of gametes, the spawning couple vibrates their bodies in close contact and it seems likely that this vibrational communication between the spawning couple, which results in a larger amplitude sound wave than seen under regular courting, reveals time of gamete release to sneaker males. Thus, vibrational communication may enable synchrony between the guarding male and the female, and this might be traded against the cost of higher detectability from surrounding sneaker males, eavesdropping in close proximity.
By obstructing competition, advantageous positioning, tailoring of sperm production, and synchronized milt release, a guarding male's sperm have increased chances of reaching the micropyle. Yet, a synchronized gamete release requires good communication, and charr seem to have developed signals to synchronize gamete release with the cost of increased detectability by surrounding males. Thus, the need for synchronization comes at the cost of sperm competition, making vibrational communication a “double‐edged sword.”
The pea leafminer (Liriomyza huidobrensis) is a notorious pest of vegetables and ornamental plants worldwide. Despite a large number of studies on its biology and ecology, the courtship behavior and ...sexual communication of this species remain unclear. Here, we studied vibrational communication in the sexual interaction of the pea leafminer. On host plant leaves, females and males behaviorally displayed the bobbing‐quivering alternation, which finally led to copulation. Moreover, records of laser vibrometry revealed three‐signal duets underlying the behavioral alternation. Sexually mature males spontaneously emitted calls (MCs) to initiate the duets. The females rapidly responded to MCs by emitting replies (FRs) that are longer in duration. The FRs further triggered male replies (MRs) in their search for potential partners. Leafminer‐produced vibrational signals convey efficient information to partners and generate pair formation on stretched substrates, such as plant leaves and nylon mesh, but cannot elicit responses on dense substrates, such as glass and plastic. Vibrational playbacks of both MCs and FRs can elicit replies in females and males, respectively. This study completely characterizes substrate‐borne vibrational duets in a dipteran insect. The discovery of vibrational sex signals in the pea leafminer provides new insights for the development of novel approaches to control the pest and its relative species.
Many bee species produce thoracic vibrations in various contexts. Among the social stingless bees (Meliponini) pulsed thoracic vibrations are used to communicate with nestmates. To date all studies ...on stingless bee vibrational communication have been conducted in the Neotropics. We, therefore, focused on six African stingless bee species of five genera:
Meliponula, Hypotrigona
,
Liotrigona
,
Dactylurina
,
Plebeina
. We analysed the signals’ temporal patterns. Vibrational signals appear to play a role in the recruitment of stingless bees. The degree of signal variation in the studied species was much lower than the variation in the signals of Neotropical stingless bees. Furthermore, the inter-signal variation of the temporal patterns exceeded intra-signal variation. This might reveal that the bees are able to modulate the temporal patterns and the signals potential communicative value. Furthermore, foraging activity correlates with pulse production in
H. gribodoi
and
M. bocandei
, supporting the hypothesis that the vibrational signals are used in the context of foraging and recruitment.
Substrate-borne vibrational communication is a common mode of information transfer in many invertebrate groups, with vibration serving as both primary and secondary signal channels in Orthopterans. ...The Cook Strait giant weta,
Deinacrida rugosa
(Orthoptera: Anostostomatidae), is an endangered New Zealand insect whose communication system has not been previously described. After field observations of intraspecific interactions in
D. rugosa
provided preliminary evidence for substrate-borne vibrational communication in the species, we sought to identify the following: vibrational signal structure, the mechanism of signal production, whether signal production is a sexually dimorphic trait, whether substrate-borne signals encode information regarding sender size, the primary social context in which vibration is utilized and finally, the function of vibrational signaling in the species. We used laser Doppler vibrometry to show that
D. rugosa
males produce low frequency (DF = 37.00 ± 1.63 Hz) substrate-borne vibrations through dorso-ventral tremulation. Rarely produced by females, male signals appear to target rivals while both are in the direct physical presence of a female. Tremulatory responses to playbacks were only produced by males in male-male-female trial contexts, and neither sex exhibited walking vibrotaxis to playback signals, indicating that substrate-borne vibrational signals are not likely a component of the courtship repertoire. While we found that vibrational signal structure was not closely related to signaler size, males that initiated male-male signaling bouts held a significant advantage in contests.
Communication using substrate-borne vibrational signals is common in hemipteran insects. In the present study, we recorded the electrophysiological responses of the peripheral vibratory receptor ...neurons in the legs of the brown-winged green bug, Plautia stali Scott（Hemiptera: Pentatomidae）. We recorded vibration-induced spike potentials using tungsten electrodes in the middle part of the meso- and meta-thoracic coxa, and applied pure sine-wave stimuli to the tarsus using a function generator. The receptor neurons exhibited different thresholds in a frequency-dependent manner； the lowest one being 50 Hz. Our results suggest that the electrophysiological responses of the peripheral vibratory receptor neurons in the legs of P. stali are generally tuned to low-frequency ranges of up to 200 Hz, corresponding to the substrate-borne vibrational signals used in inter- or intra-specific communication.
Many species spend their lives in close association with other organisms, and the environments provided by those organisms can play an important role as causes of variation in phenotypes. When this ...is the case, the genotypes of the individuals constituting the environment may influence the phenotypes of individuals living in that environment. When these effects are between heterospecifics, interspecific indirect genetic effects (IIGEs) occur. Several studies have detected IIGEs, but whether IIGEs contribute to variation in sexually selected traits remains virtually unexplored. We assessed how mate preferences in a plant-feeding insect are influenced by the genotype of their host plant. We established clone lines of a sample of host plant genotypes constituting the background biotic environment for a random sample of insects that we reared on them. We found that the insects’ mate preferences varied according to the clone line on which they developed. These results demonstrate that genetic variation in host plants has cross-trophic consequences on a trait that has strong effects on fitness and interpopulation dynamics such as diversification in communication systems. We discuss how IIGEs on mate preferences may influence the way in which selection acts, including the maintenance of variation and the promotion of evolutionary divergence.
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