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Courtship vibrations of male Tegenaria agrestis. For each of the courtship vibrations including (1) palp drumming, (2) walking, drumming and tapping, (3) jerks, walking, drumming and tapping, and (4) stretches produced by courting Tegenaria agrestis males on empty webs of conspecific females, the upper panel depicts vibrations in the time domain and the lower panel depicts vibration in the frequency domain. The insert in (1) depicts the amplitude of palp drumming (maximum baseline-to-peak amplitude = 0.3 mm/s) magnified 25 times.
Source publication
Female spiders are fine-tuned to detect and quickly respond to prey vibrations, presenting a challenge to courting males who must attract a female's attention but not be mistaken for prey. This is likely particularly important at the onset of courtship when a male enters a female's web. In web-dwelling spiders, little is known about how males solve...
Context in source publication
Context 1
... fly vibrations also contained a high- frequency component (~ 200 Hz) corresponding to wing beats. Courting T. agrestis males produced four distinct types of vibrations: (1) drumming with their pedipalps produced continuous, low-amplitude and low-amplitude- modulation vibrations unique to males; (2) walking on webs while pedipalp-drumming and tapping with the first pair of legs produced sustained vibrations of varying amp- litude (high AMF); (3) jerks (see methods) produced brief and highly percussive types of vibrations that resembled those of prey but were always followed by continuous vibrations associated with walking on the web while drumming and tapping; and (4) percussive vibrations which were always preceded and followed by silence ( Figure 5). ...Similar publications
Objective: We analyze the processing sequence involved in the manufacture of a skull‐cup and the manipulation of human bones from the Early Neolithic of Cueva de El Toro (Málaga, Spain). Materials and methods The Early Neolithic material studied includes human remains found in two separate assemblages. Assemblage A consists of one skull‐cup, a non‐...
Nutrition is the single most important factor for individual's growth and reproduction. Consequently, the inability to reach the nutritional optimum imposes severe consequences for animal fitness. Yet, under natural conditions, organisms may face a mixture of stressors that can modulate the effects of nutritional asymmetry. For instance, stressful...
Citations
... obs.), we counted the number of following putative deterrent behaviours by females: (1) 'lunges' when the female rapidly approached the male in a manner similar to predation behaviour; (2) 'abdominal twitches' represented by vigorous vibrations of the female's abdomen in response to an approaching male and (3) 'foreleg strikes': rapid flicking movements of the female's front legs when touched by the male [23,47]. Further, throughout the whole recordings lasting 12 hours, we quantified components of male courtship in terms of how much time the male invested in (1) 'distal courtship' [21,23]: latency from the start of the trial to the first mount (defined as when the male first moves onto the female's ventral abdominal surface, which is the location of the female's genital openings), and (2) 'proximal courtship' [21,23,[48][49][50]: latency from the first mount until the copulation. We also counted the number of mounts males performed before the first copulation [23] or, if copulation did not occur, the number of mounts during the recorded 12 hours as another indicator of courtship effort. ...
Background:
The 'wallflower' hypothesis proposes females mate indiscriminately to avoid reproductive delays. Post-copulatory mechanisms may then allow 'trading up', favouring paternity of future mates. We tested links between pre- and post-copulatory choice in Latrodectus geometricus female spiders paired sequentially with two males. These females copulate as adults or as subadults and store sperm in paired spermathecae. Choosy adults have a higher risk of delays to reproduction than subadults.
Results:
We predicted low pre-copulatory, but high post-copulatory choice at first matings for adults and the opposite for subadults. At second matings, we expected all females would prefer males superior to their first. We found all females mated indiscriminately at their first pairing, but in contrast to subadults, adults usually allowed only a single insertion (leaving one of their paired spermatheca empty); a mechanism of post-copulatory choosiness. Adult-mated females were more likely to remate than subadult-mated females when they became adults, showing a preference for larger males, while subadult-mated females tended to prefer males of greater size-corrected mass.
Conclusions:
Our results show that the 'wallflower' effect and 'trading up' tactics can be utilized at different life stages, allowing females to employ choice even if rejecting males is costly.
... Mating communication in L. hesperus is mediated by chemical and vibrational signals (Vibert et al. 2014(Vibert et al. , 2016. Males use pheromones from female webs to localize mates (Ross and Smith 1979) and, upon arriving on female webs, males initiate courtship behaviors characterized by the production of web-transmitted vibrations (Vibert et al. 2014). ...
... Mating communication in L. hesperus is mediated by chemical and vibrational signals (Vibert et al. 2014(Vibert et al. , 2016. Males use pheromones from female webs to localize mates (Ross and Smith 1979) and, upon arriving on female webs, males initiate courtship behaviors characterized by the production of web-transmitted vibrations (Vibert et al. 2014). During mating communication, males display three distinct types of signals (abdominal tremulation, bounce, and web plucks) (Sivalinghem and Mason 2021), that differ from vibrations produced by prey (Vibert et al. 2014). ...
... Males use pheromones from female webs to localize mates (Ross and Smith 1979) and, upon arriving on female webs, males initiate courtship behaviors characterized by the production of web-transmitted vibrations (Vibert et al. 2014). During mating communication, males display three distinct types of signals (abdominal tremulation, bounce, and web plucks) (Sivalinghem and Mason 2021), that differ from vibrations produced by prey (Vibert et al. 2014). While male and female L. hesperus are known to use vibrational signals in mating communication, little is known about female-female communication behaviors in this species. ...
Female black widow spiders, Latrodectus hesperus Chamberlin and Ivie (Araneae: Theridiidae), are solitary predators of arthropods with no tolerance for intruders on the webs. In California, L. hesperus are found in urban and agricultural settings and can be a phytosanitary pest in fresh produce. Spatial separation of L. hesperus webs could be determined by seasonal population densities, with territorial competition expected under high densities in the environment. However, little is known about female-female communication behaviors in this species. In 1-hr laboratory observations, displays of female-female rivalry included production of vibrational signals in a majority (20 of 30) of trials. The number of signals produced by both females was highest during the initial 10 min of trials, with signaling rate (time interval between signals) peaking during the 40-50 min observation period. The overall ratio of signals produced by the resident female and the introduced female was about 5:1, with the number of signals produced by the resident female higher than the number of signals produced by the introduced female. Analysis of rivalry signals showed a peak in magnitude (about 0.4 m/s) ranging from 6 to 23 Hz and smaller peaks at about 29, 38, and 47 Hz. Collectively, these results demonstrate that female L. hesperus exhibit territorial rivalry and that female-female rivalry is mediated by emission of vibrational signals through the web. Understanding the mechanisms of intraspecific competition in L. hesperus is required for elucidating interspecific interactions in the environment and may lead to development of novel methods to prevent spiders from colonizing crops.
... The current state-of-the-art method for the vibration analysis of spider-related signals is laser Doppler vibrometry, which has commonly been used to examine the webs of L. hesperus [9][10][11][12][13] and both three-dimensional webs and planar orb webs built by other species [2][3][4][5]14,15]. A typical experiment utilizing a laser vibrometer involves recording vibrational data using one or more laser vibrometers aligned against the web structure or against the body of a stationary spider while the web is undergoing excitation from some signal, typically a shaker that can oscillate the web at a chosen range of frequencies. ...
... The insights gained by this spiderweb vibrometry are diverse. Previous studies have examined such things as the signal attenuation in webs for the different vibrational modes to hypothesize which propagation modalities in the web might carry the most consistently valuable information for a spider [2][3][4]10], the speed of sound and tension in webs to hypothesize how a spider might perform prey localization [4,14] or tune its web to create the most beneficial acoustic characteristics [15,16], and the vibratory characteristics of prey and mate signals that correlate to whether the owner of the web illicits a predatory or a courtship response [9,10]. ...
Simple Summary
Spiders often use their webs as sensory mechanisms, obtaining from them such information as the location of prey, the presence of rival spiders, and the characteristics of potential mates. Examining how this information is transmitted through the web and received by spiders is a promising biological area of research that could provide insight into a spider’s world and lead to new technologies that leverage these discoveries. In this paper, we develop a novel noncontact technique using two video cameras that is capable of analyzing vibrational signals transmitted through spiderwebs and validate this technique against the current standard of laser Doppler vibrometry. By combining the principles of stereo vision and video vibrometry, we can automatically extract three-dimensional vibrational information at any point in the spiderweb across time, and study how these signals propagate through the web. We show that this technique produces results comparable to those of standard laser vibrometry.
Abstract
From courtship rituals, to prey identification, to displays of rivalry, a spider’s web vibrates with a symphony of information. Examining the modality of information being transmitted and how spiders interact with this information could lead to new understanding how spiders perceive the world around them through their webs, and new biological and engineering techniques that leverage this understanding. Spiders interact with their webs through a variety of body motions, including abdominal tremors, bounces, and limb jerks along threads of the web. These signals often create a large enough visual signature that the web vibrations can be analyzed using video vibrometry on high-speed video of the communication exchange. Using video vibrometry to examine these signals has numerous benefits over the conventional method of laser vibrometry, such as the ability to analyze three-dimensional vibrations and the ability to take measurements from anywhere in the web, including directly from the body of the spider itself. In this study, we developed a method of three-dimensional vibration analysis that combines video vibrometry with stereo vision, and verified this method against laser vibrometry on a black widow spiderweb that was experiencing rivalry signals from two female spiders.
... Courtship mostly occurs within a contained environment (the web), which places constraints on signal evolution. Males entering female webs must ensure that they have mechanisms in place to reduce the risk of sexual cannibalism (Wignall and Herberstein 2013b;Herberstein et al. 2014;Vibert et al. 2014), whilst still attracting the attention of the female. We have recently described a mechanism that reduces the risk of cannibalism in the courtship shudders of the St Andrew's cross spider Argiope keyserlingi (Karsch) (Wignall and Herberstein 2013a;Wignall and Herberstein 2013b). ...
... curta) reduced female aggression similar to the shudder vibrations in our experiments (Xiao et al. 2015). However, similar playback experiments with L. hesperus demonstrated that females do not respond aggressively to playbacks of any low amplitude vibrations, whether they be from males or prey (Vibert et al. 2014). It may be that we should also be asking questions about the stimuli that elicit female aggressive behaviors, in addition to questions about stimuli that suppress aggressive behaviors. ...
Male courtship serves multiple functions in addition to inducing females to accept them as a mate. In predatory species, male courtship can function to reduce the risk of sexual cannibalism. This is particularly important in web-building spiders in which males risk being mistaken for prey when they enter the female’s predatory trap—the web—in order to commence courtship. Male spiders generate vibrations by shuddering in the female’s web. Shudder vibrations can delay female aggression, even toward prey struggling in the web. We predicted that shudder vibrations are highly conserved across species of web-building spider as males all face the same constraint of not being mistaken for prey by females. We examined how conserved shudder vibrations are across web-building spiders by testing whether female Trichonephila plumipes delay aggressive behavior toward real prey struggling in the web during playback of conspecific or heterospecific (Argiope keyserlingi) male shudder vibrations. We found that while conspecific shudder vibrations do indeed delay female predatory behavior, heterospecific male shudder vibrations do not. There is evidence of shudder or shudder-like vibrations in male courtship behavior across web-building spider families, but these vary in structure. This suggests that despite strong constraints on courtship signal design to separate predatory responses from sexual responses, there is additional selection driving the divergence of signals across distantly related spider species.
... For each trial, we noted the timing of the commencement of the male courtship activity, and whether it occurred throughout the trial. The behaviours associated with the production of vibrational signals on the web or on the female's body are visible to the naked eye (e.g., [87,88]). For pairs that mated, we recorded the number of copulations (airborne and cohabitation experiments), and the occurrence and timing of cannibalism relative to copulation (cohabitation experiment). ...
Female choice may be linked to population density if the expected encounter rates with potential mates affects choosiness (the energy and risk engaged to express mate preferences). Choosiness should covary with male availability, which could be assessed using the social cues available during development. We tested whether the exposure of juvenile females to cues of male density affected the mechanisms of choosiness of adult Latrodectus hasselti spiders in two experiments simulating natural contexts. The juvenile females were exposed to (1) volatile chemicals from two densities of adult males (airborne cues), and (2) tactile, vibrational and chemical cues from adult males or other females (cohabitation cues). As adults, the females mated readily, regardless of the treatment, but there was strong evidence for post-copulatory mechanisms of choosiness in females exposed to cues of high male availability. These included abbreviated matings (in both experiments), cannibalism of the males before the mating was complete (cohabitation), and, remarkably, a reduction in the successful placement of internal sperm plugs (cohabitation). These shifts decrease the likelihood that the first mate would monopolize paternity if the female chose to mate again. We conclude that female choosiness may impose a strong selection on males despite the high mating rates, and these effects can hinge on the cues of male availability detected by juveniles.
... In addition, males vary signal structure during courtship by gradually adding new components as well as changing motifs, with signal display rates gradually building to a 'crescendo' (Elias et al., 2012). In contrast to highly organized signals of many cursorial spiders, the courtship signals of web-building spiders have been thought to be relatively simple, with minimal structure (Herberstein et al., 2014;Lubin, 1986;Vibert et al., 2014). In a previous study, however, we showed that during the course of an extended courtship, male western black widow spiders, Latrodectus hesperus, intermittently transition between production of relatively less complex 'haphazard' discrete signal elements to production of a more complex stereotyped sequence that combines individual signal elements into a multicomponent signal display (organized sequence) (Sivalinghem & Mason, 2021). ...
... The abdominal tremulation signals of L. hesperus males may have a different functional role, and attenuating this signal component may not necessarily affect male mating success. Previously, Vibert et al. (2014) showed that male abdominal tremulation signals reduced the probability of female attack, which suggests that females may use the low-amplitude abdominal tremulation signals to discriminate mates from prey. In our previous study, we showed that, unlike male bounce and web pluck signals, abdominal tremulation signal characteristics are not associated with male traits (Sivalinghem & Mason, 2021). ...
Many animals communicate using complex signals composed of multiple components. In some, multiple distinct signal components are organized into stereotyped sequences. Few studies, however, have examined how such temporal structure might arise, or how this structural complexity relates to signal function. Male black widow spiders (Latrodectus hesperus) intermittently transition from a ‘haphazard’ production of three distinct vibratory signal components to a temporally structured multicomponent display during courtship. In this study, we examined the function of structured signalling during courtship in L. hesperus. More specifically, we examined whether structured signalling rates is predicted by male mass and whether structured signalling rates predict male mating success. Then, we experimentally tested the consequences of removing one of the signal components (abdominal tremulation) for male mating success. Larger males had lower signalling rates, suggesting a trade-off between structured signalling and mass. Males that produced structured signals more frequently mated sooner. Impairment of abdominal tremulation did not affect copulation success, but these ‘muted’ males took significantly longer to mate. Our study demonstrates that the temporal arrangement of signal components is important for male mating success in L. hesperus.
... Courtship follows a sequence of similar steps in most Latrodectus species where it has been described (Kaston, 1970;Stoltz et al., 2009;Andrade, 2017, 2020). Males initiate vibrations and other behaviours shortly after coming into contact with the web in the 'distal' phase of courtship (Vibert et al., 2014;Sivalinghem and Mason, 2021). In the 'proximal' phase of courtship, males alternate between mounting the female's abdomen and dismounting to continue courtship on the web (Baruffaldi and Andrade, 2017). ...
Sexual cannibalism is an extreme form of sexual conflict that may have broad evolutionary effects on mating behaviour. Latrodectus spiders (∼30 "widow" species) could enable comparative tests of the evolution of sexual cannibalism, but most species are poorly-studied. Here we describe the mating and remating behaviour of a species endemic to South America, L. mirabilis, with a focus on the occurrence and consequences of sexual cannibalism. Mating and cannibalistic behaviours were novel relative to other Latrodectus species. Cannibalism started during copulation when females grasped the male's legs with their chelicerae, and continued as females pulled the male's abdomen onto their chelicerae, without interrupting copulation. Cannibalism was initiated by females, and not facilitated by males as was observed in other Latrodectus species. Females frequently remated however, so cannibalized males might lose paternity to future rivals. We report high rates of cannibalism, with 70% of males killed by females during their first mating, and 85% killed by previously-mated females. We discuss our novel findings in the context of previous observations in other Latrodectus species, proposing that foundational studies in a wider range of species are necessary to support comparative tests about the evolution of sexual cannibalism within this model taxon.
... For example, Whitehouse and Jackson (1994) observed 32 different types of male courtship vibratory behaviours in the kleptoparasitic spider Argyrodes antipodiana. Despite this, empirical studies on vibratory communication in webdwelling spiders are scarce, and we know very little about the characteristics of the signals involved or their functions and mechanisms (but see Herberstein et al., 2014;Vibert, Scott, & Gries, 2014;Wignall & Herberstein, 2013a, 2013b. ...
... The majority of studies only provide qualitative descriptions of the signals, general vibration behaviours of males and/or the conspicuous movements of body parts (Aisenberg, 2009;Barrantes, 2008;Forster, 1992;Ross & Smith, 1979;Singer et al., 2000). Only recently have a few studies recorded and characterized web-borne vibratory signals in some orb-web and cobweb spiders (Vibert et al., 2014;Wignall, Kemp, & Herberstein, 2014;Wignall & Herberstein, 2013a, 2013b. Male Argiope keyserlingi use vibratory signals that are different from prey-generated vibrations; at least one of these signals (male 'shudders') reduce female predatory behaviours and convey information about male traits to influence female mate choice Wignall & Herberstein, 2013a, 2013b. ...
... Recently, Vibert et al. (2014) characterized vibrations of courting male L. hesperus using laser vibrometry. Specifically, they focused on male abdominal tremulation signals during the early phase of courtship as males entered female webs. ...
Despite the ubiquity of web-borne vibratory communication among many web-building spiders, few empirical studies, to date, have quantified the characteristics and mechanisms of the signals involved. In this study, we used western black widow spider, Latrodectus hesperus, and examined male signal characteristics, signal production mechanisms and signal transmission efficacy on webs. It is not clear how vibrations are transmitted through the chaotic cobweb typical of this species and relatives, and previous work argued that L. hesperus courtship vibrations lacked structure. We videorecorded courtship and copulation behaviour, and used laser vibrometry to record and characterize web-borne vibrations. We examined signalling mechanisms using synchronous high-speed video and vibrometry recordings. Lastly, we examined signal transmission by measuring transfer functions between body movements and the resulting vibration signal. We found that males displayed three distinct signal types (abdominal tremulation, bounce and web plucks), each of which were generated by a different signal production mechanism. Our results also show that male bounces and web plucks may convey information about male size. Contrary to earlier work, we show that during the later phases of male–female interactions, males intermittently organize individual signal types into stereotyped sequential displays (‘structured signalling’). Moreover, despite the cobweb structure, transfer function analyses showed that female webs transmit male signals with high efficacy. These results suggest that vibratory communication in L. hesperus, previously classified as simple signallers, can comprise emergent forms of signal complexity and lay the foundation for future studies on this mode of communication in other web-dwelling species.
... Instead, aggressiveness and web structure could covary in a heterogenous environment where disruptive or oscillating selection acted on each trait independently to either minimize mortality risk or maximize foraging success (DiRienzo and Montiglio 2016b). Other contexts in which web structure may be under selection are mating (male courtship cues are transmitted through the web; Vibert et al. 2014), offspring protection as females build protective silk funnels around their egg cases (DiRienzo and Aonuma 2018), and defense against conspecifics (DiRienzo N, unpublished data). However, our experimental design did not include predators or mating partners and thus we did not test for any correlational selection outside the foraging context. ...
Multiple phenotypic traits often interact with each other to determine an individual’s fitness. Behavioral and extended phenotypic traits, such as architectural constructions, can contribute to fitness in an integrated way. The goal of this study was to understand how the interaction between behavioral and extended phenotypic traits can affect foraging success. We tested this question using black widow spiders, where spiders that are aggressive in a foraging context tend to build more gumfooted silk lines that aid in prey capture, while non-aggressive spiders build webs with fewer gumfooted lines. We repeatedly assessed behavior and web structure to quantify relationships between these traits, and then allowed spiders to forage for live prey on their own web or the web of a conspecific that differed in structure. Thus, we assessed how varying combinations of behavior and web structure affect foraging success, and if correlational selection might act on them. We confirmed that aggressiveness and number of gumfooted lines are positively correlated and found that capture success increased with both aggressiveness and the number of gumfooted lines. Yet, we did not find any evidence for correlational selection: aggressiveness and number of gumfooted lines appeared to affect foraging success independently of each other. These findings highlight that a correlation between traits that contribute towards the same ecological function does not necessarily imply correlational selection. Taking advantage of the experimental convenience afforded by extended phenotypic traits can provide insight into the functional consequences of phenotypic variation within and between individuals.
... Indeed, a web-building female sitting on her web must quickly decide whether to launch an attack as soon as vibrations are detected and male must evade cannibalism. In many species, males thus produce distinctive vibrations that reduce the risk of being attacked by females during courtship Vibert et al. 2014). In the orb-web spider Argiope keyserlingi, for instance, the playback of courtship shudders of males on a female's web delayed her attack toward a live prey but the playback of a white noise had no effect, which indicates that the seismic signal produced by males contains elements that inhibits the expression of predatory behaviour in females (Wignall and Herberstein 2013). ...
When foraging in a group, individuals adjust their behaviours to the actions of others in order to optimize their pay-offs. While many studies have examined the influence of group composition on behavioural strategies, relatively few have investigated how the presence or absence of conspecifics influences the expression of behaviours during hunting. Another aspect that has received little attention concerns the impact of prior social experience on the expression of predatory behaviour. Here, we studied how past and present social contexts influenced predatory behaviour in juveniles of the spider Agelena labyrinthica which, like most solitary species, exhibit a transient gregarious phase prior to dispersal. We tested, alone or in pairs, spiderlings that have been maintained in isolation or in groups for 24 h prior to behavioural assays. During the tests, we introduced a live prey to an experimental arena and we measured the latencies associated with the different phases of the hunting sequence. We found that spiders maintained in isolation captured prey faster than those kept in groups and that the presence of a sibling increased the latency of prey capture compared with individuals hunting alone. Such a social context effect adds another dimension to the already complex combination of factors that determine the success of spider foraging. Overall, our study reveals an influence of the social dimension, past and present, on hunting behaviour that may have been underestimated in carnivores.
Significance statement
It is generally considered that hunting in group increases individual benefits compared with solitary hunting. However, relatively few studies have compared hunting performance between individuals hunting alone or in group to assess how the presence of conspecifics impacts the expression of predatory behaviours. Another aspect that has been little explored concerns the role of the social context previously experienced on hunting behaviour. This study examined the influence of past or present social context on hunting behaviour in juveniles of a solitary spider during their gregarious phase. We showed that spiderlings maintained in isolation or tested alone were faster at catching prey than congeners reared socially or tested in groups. This study highlights a cost to sociality that has so far received little attention, and which could be an important element to consider in understanding transitions to permanent sociality.
