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, Gaƫlle1 aGreenfield, Michael, D. uhttps://bio.acousti.ca/nn/node/5845601988nas a2200133 4500008004100000245007200041210006900113520154900182100001701731700001501748700002801763700002201791856004101813 2001 eng d00aDUET SINGING AND FEMALE CHOICE IN THE BUSHCRICKET PHANEROPTERA NANA0 aDUET SINGING AND FEMALE CHOICE IN THE BUSHCRICKET PHANEROPTERA N3 aIn the phaneropterine bushcricket Phaneroptera nana both males and females sing, producing a duet. The male's song is answered by a short female 'tick'. A male that receives a response in a defined interval after the end of his chirp usually initiates phonotaxis toward the female. Measurements of temporal, spectral, and energy characters of male chirps indicate that individual males vary considerably in several temporal song characters. Females exhibited equivalent response rates to solitary singing males in laboratory trials regardless of their song characters. However, when simultaneously presented with two singing males, females showed consistent preferences: They responded preferentially to relatively longer chirps produced by larger males. Male chirp rate had no influence on female response, suggesting that females were not influenced by a summation of acoustic input integrated over multiple chirps. Rather, female 'decisions' to respond were probably made following individual chirps. The selective responses exhibited by Ph. nana females contradict some previous expecta- tions that females in duet signalling systems should be indiscriminate. Selectivity may reflect the reliability with which females can assess male song at a distance and potential disadvantages of attracting multiple suitors. Laboratory trials indicated that only males receiving a high female response rate actually approach and mate with the female. Thus, this duet signalling system may be relatively resistant to intraspecific exploitation.1 aTauber, Eran1 aCohen, Dan1 aGreenfield, Michael, D.1 aPener, Meir, Paul uhttps://bio.acousti.ca/nn/node/5844902551nas a2200157 4500008004100000022001400041245010500055210006900160260001600229300001400245490000800259520199200267100002102259700002802280856008502308 1989 eng d a0005-795900aSatellites and Transients: Ecological Constraints On Alternative Mating Tactics in Male Grasshoppers0 aSatellites and Transients Ecological Constraints On Alternative  cJan-01-1989 a200 - 2200 v1093 a

Alternative tactics of male mating behaviour, broadly classifiable as "dominant/ territorial" versus "subordinate/non-territorial", have now been described for numerous species. Furthermore, across diverse taxa the mating tactics of subordinate/non-territorial males often appear as one of two distinct types, satellite or transient behaviour. Despite general recognition of this dichotomy, though, little effort has been made to identify the circumstances under which one of these behaviours is adopted over the other. We compared the mating systems of two congeneric species of desert grasshoppers (genus Ligurotettix) to investigate specifically the role of resource dispersion in shaping the behaviour of subordinate males. The utility of the comparative approach derives from two basic similarities between the species: both Ligurotettix coquilletti and Ligurotettix planum feed almost exclusively on a single host plant species, and the majority of males in both species defend individual host plants to gain access to females. However, the two species are associated with host plants that are dispersed very differently; i.e., L. coquilletti encounter a small number of large plants and L. planum a large number of small ones. In L. coquilletti, subordinate males, individuals noted by their lack of success in aggression and in obtaining matings, were characterized as satellites that remained silent on host plants defended by territorial males. Subordinate males in L. planum, however, were transients that sang regularly but moved frequently among different host plants. We propose that this behavioural discrepancy results from (1) the large difference between the number of potential female encounter sites (i.e., individual host plants) available to the males of the two species and (2) the large difference between the sizes of resource patches defended by the two species, which influences the ability of dominant males to eject subordinates.

1 aShelly, Todd, E.1 aGreenfield, Michael, D. uhttp://booksandjournals.brillonline.com/content/journals/10.1163/156853989x0023101956nas a2200145 4500008004100000022001400041245004800055210004800103260001600151520144000167100002801607700002601635700002001661856012901681 2017 eng d a0024-406600aEvolution of synchronies in insect choruses0 aEvolution of synchronies in insect choruses cFeb-09-20173 a

In many acoustic insects, neighbouring males adjust their calling rhythms and broadcast a temporally structured chorus ranging from an irregular mixture of alternation and synchrony to a nearly perfect synchrony wherein most males sing in unison. Irregular synchrony can arise where females ignore calls that follow a neighbour’s call by a brief delay, a perception that selects for competitive male adjustments to calling rhythm that increase leading calls and ultimately yield alternation and synchrony. Such chorusing emerges as an incidental property, and the collective temporal structure may have little significance for females and males. More perfect synchronies are expected where females must perceive distinct sound envelopes before approaching a chorus or a given male. Here, selection will favour cooperative male adjustments by which neighbours align their calls, as any male who does not adjust would reduce the group’s attractiveness and therefore his own. We tested these expectations in two sympatric bushcrickets, Ephippiger diurnus and Sorapagus catalaunicus, that exhibit irregular and more perfect synchrony, respectively. We found, however, that females in both species prefer leading calls and must hear distinct sound envelopes. We infer that fundamental differences in perception and singing influence the relative importance of competition and cooperation, producing the two synchronies.

1 aGreenfield, Michael, D.1 aMarin-Cudraz, Thibaut1 aParty, Virginie uhttp://academic.oup.com/biolinnean/article/doi/10.1093/biolinnean/blx096/4103004/Evolution-of-synchronies-in-insect-choruses