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Psyche 
[September-December 
B. Stridulation and substrate vibration 
Physical combat was always associated with other behavior 
whose probable function was intimidation. As also noted by 
Howden and Campbell (1974), beetles produced soft “squeaking” 
or “chirping” sounds. These were made before, during, and after 
battles, and were the result of scraping a file running longitudinally 
on the dorsum of the tip of the abdomen back and forth against 
the tips of the elytra. The number of chirps varied from two (one 
downward and one upward stroke) to more than 20; chirps were 
made as fast as about 12 strokes/ sec. Beetles being teased with a 
finger gave a single pair of chirps accompanying each thrust with 
the head horn. 
Males also sometimes shook the entire stalk by vibrating the 
body rapidly from side to side (about 10 cycles/ sec) while resting 
in one place. This behavior was usually performed by a winning 
beetle just after a battle, and was accompanied by simultaneous 
stridulation. 
C. Climbing and flying behavior 
The males’ long front legs were not the encumbrance to walking 
along the stalk that might be expected. They were held bent ven- 
trally so that the two tibiae touched each other, or nearly so, on 
the other side of the stalk, and were used in a manner similar to 
that of telephone linemen using belts as they climb poles. Beetles 
climbing upward moved each pair of legs simultaneously, the order 
being middle, hind, and, just slightly later, front. Descending bee- 
tles moved their legs in a similar manner, with the added variation 
that the strong spurs on the inner margins near the tips of the 
tibiae were apparently used as spikes to engage the stalk. 
Beetles sometimes decamped after fights by climbing to the up- 
per tip of the stalk and flying away. They flew strongly, and could 
hover more or less stationary for seconds at a time. They held their 
front legs folded with their tarsi projecting forward and upward, so 
that they reminded one, with these paired, hook-shaped structures, 
of a bat hanging by its hind legs. 
Discussion 
There seems little doubt, from the combination of observations 
of fights in nature and in captivity, that the horns and elongate 
front legs of G. ported males function in fights between conspe- 
