02397nas a2200205   4500008004100000022001400041245010100055210006900156260001600225300001400241490000800255520172600263653002101989653002302010653001802033653001502051100002702066700002102093856007702114       2005                        eng d  a0005-795900aAlternate tactics in male bladder grasshoppers Bullacris membracioides (Orthoptera: Pneumoridae)0 aAlternate tactics in male bladder grasshoppers Bullacris membrac  cJan-06-2005  a761 - 7780 v1423 a<p>Bladder grasshoppers (Orthoptera, Pneumoridae) are a unique group of nocturnal, specialized herbivores, endemic to coastal regions of Southern Africa. Adult males are characterized by an inflated abdomen, which develops at the final molt, and a signaling system capable of producing high intensity calls detectable by conspecifics at distances of up to 2 km. Female response to male calls leads to reciprocal duetting and pair formation. We have found an alternative form to the dominant inflated male tactic in three pneumorid species. These alternate males are incapable of flight and lack the air-filled abdominal bladder used in long-range acoustic communication; but may be found in copula with mature females in the field. Here we address the issue of neoteny/paedogenesis in the alternate male by comparing the morphology of inflated and uninflated adult male Bullacris membracioides with that of ultimate and penultimate nymphal instars, to determine whether these forms follow a common developmental trajectory. We then compare the behavioral responsiveness of inflated and noninflated morphs to conspecific advertisement calls, to ascertain whether alternate males have the potential to actively exploit the mate location system of duetting pairs. Morphometric analyses indicate that alternate males are a distinctly divergent form from the primary male developmental tactic. We conclude that males following the alternate tactic eavesdrop on the duets of inflated males and females to exploit the acoustic mate location system. This satellite tactic has potential impact on several aspects of pneumorid biology contributing to biasing sexual selection, sensory drive, and ultimately speciation events.</p>
10aalternative male10abehavioral tactics10acommunication10amorphology1 avan Staaden, Moira, J.1 aDonelson, Nathan  uhttp://booksandjournals.brillonline.com/content/10.1163/156853905472908802782nas a2200289   4500008004100000245017800041210006900219260001600288300001400304490000700318520179900325653002102124653002202145653003202167653001402199653002402213653002802237653002102265653002702286100002202313700001802335700001602353700001602369700001902385700001902404856006902423       2005                        eng d00aInheritance of song and stridulatory peg number divergence between Chorthippus brunneus and C. jacobsi, two naturally hybridizing grasshopper species (Orthoptera: Acrididae)0 aInheritance of song and stridulatory peg number divergence betwe  cJan-05-2005  a703 - 7120 v183 a<p>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&ndash;Castle&ndash;Lande estimates of the minimum numbers of genetic factors underlying song and peg number divergence were low: peg number ( n e &frac14; 5.87 &plusmn; 5.84), SL ( n e &frac14; 2.37 &plusmn; 4.79) and PL ( n e &frac14; 0.87 &plusmn; 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.</p>
10aadditive effects10adominance effects10aeffective number of factors10aepistasis10amosaic hybrid zones10aquantitative trait loci10asexual selection10awavelet transformation1 aSadamando, C., I.1 aMiyaguchi, S.1 aTatsuta, H.1 aKishino, H.1 aBridle, J., R.1 aButlin, R., K.  uhttp://blackwell-synergy.com/doi/abs/10.1111/jeb.2005.18.issue-3