MANTIS MOVEMENTS BY NIGHT AND THE INTERACTIONS OF SYMPATRIC BATS AND MANTISES

Bat-insect interactions should be a useful source of case studies for the ''arms race'' of predator and prey adaptations; currently, well-de tailed examples are needed for the formulation of general hypotheses. In this paper I add to information on bat-mantis interactions, testing four predictions of the hypothesis that mantises with ears can detect and avoid bats: that mantises will fly by night, that they will be vu lnerable to bats, that echolocating bats will be better at catching de afened than normal mantises, and that mantises which can hear bats' ca lls will take evasive action. I found that tagged Miomantis cf. natali ca Beier flew substantially on dark nights; indoors, undeafened mantis es were better at avoiding Rhinolophus clivosus (Rhinolophidae: Microc hiroptera) than were deafened mantises (n = 20 pairs; Mann-Whitney tes t, z = 4.58, p < 0.001). Rhinolophus clivosus echolocates at 80-85 kHz , implying that M. cf. natalica can hear higher frequencies than most mantises (the usual best frequencies for mantises are 30-60 kHz); this is supported by D.D. Yager, who found that two other Miomantis specie s can hear at 80-150 kHz. The development of higher frequency hearing in Miomantis spp. was probably driven by predation from rhinolophid an d hipposiderid bats, many of which echolocate at frequencies over 60 k Hz. These taxa would be suitable for further research into predator-pr ey coevolution.