02782nas 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