W. Kutsch et Mp. Pener, MUSCLE-ACTIVITY UNDERLYING SEXUAL-BEHAVIOR IN MALE LOCUSTS (LOCUSTA-MIGRATORIA) AFTER NORMAL AND HORMONALLY DISTURBED DEVELOPMENT, Physiological entomology, 22(1), 1997, pp. 47-54
The activities of three sets of muscles, representing the major compon
ents of the abdominal muscle system, were recorded in the pregenital a
bdominal segments of adult males of Locusta migratoria. The muscular a
ctivities were associated with three consecutive actions of the male's
mating behaviour: abdominal lowering, S-bending and hooking-up. These
three actions depend mainly on the relative coordination of the dorsa
l versus ventral longitudinal muscles; the activity of the dorsoventra
l muscles is rather unpredictable, except in the sixth and seventh abd
ominal segments where they are regularly involved in hooking-up. Studi
es on male sexual behaviour-linked muscle activity in precocene-induce
d fifth-instar adultiforms and azadirachtin-induced fifth-instar over-
aged nymphs revealed no distinct differences between these creatures a
nd normal mature males. Therefore the muscle activities associated wit
h these adult-specific behavioural acts can be released precociously,
i.e. their occurrence is not dependent on a distinct series of instars
. Moreover, the results obtained with over-aged nymphs demonstrate tha
t morphogenesis and ethogenesis (i.e. formation of neural circuits con
trolling adult-specific behaviour) are not closely dependent on each o
ther.