1972] 
McCluskey & Brown — Paraponera 
345 
Finally, the ants in the field were observed only for a few days and 
in only one season; perhaps they differ at other times. However, a 
predominantly crepuscular-nocturnal timing in the field is supported 
by observations of WLB made in Costa Rica in 1966 and in the 
Amazon Basin in 1967 and 1971, and by Hermann and Blum’s 
(1966) statement that they collected Paraponera “in the evenings, 
just before ants left their nests to forage during the night.” In con- 
trast is a very brief statement by Mann (1916): “In habit it is 
diurnal.” 
Males, females, and workers were all studied in LD and in DD, 
each caste in isolation from the others. This permits a comparison 
of their inherent rhythmicity. In LD (Fig. 5) the males were active 
at night, especially the first hour, and inactive throughout the light 
period. The one female was active especially before and after the 
lights went off and from late night through the first hour of the 
light. The peaks for the workers were within the light period. In 
DD (Fig. 3 and 4) there was evidence for persistence of rhythm 
in the males and the female, but not the workers. Thus there was 
an interesting contrast in timing between the castes. However, the 
limited number of specimens studied precludes pressing this conclu- 
sion very far. 
In the same darkroom the same year, a striking difference in phase 
relationship was demonstrated between males and workers of another 
ant, Carnponotus clarithorax (McCluskey, 1965). The males were 
Fig. 5. Rhythms of males, of female, and of workers in LD, records 
for all available days combined. Means ± SE are based on different days 
as replicates except in (C) where different ants are the replicates. Tun- 
nel count (histograms) and Arena count converted to hourly percentage of 
24-hour total before deriving mean, SE, and ANOVA. One-way ANOVA’s 
give P<.001 for each of the six rhythms shown except for Arena (<.05). 
For the point plots the first count after midnight is repeated. Bar at top 
indicates light on 12 hr from vertical dawn line (solid) until dusk line 
(dashed). A) Same group of 3 males as in Fig. 3; N == 4-5 days (Feb. 3- 
9); graph in McCluskey (1965) based on same data. B) Same female as 
in Fig. 3 and 4; Tunnel, N = 9 days (Feb, 8-9, Mar. 2-4 & 8-15) ; Activ- 
ity, N = 4-6 days (Mar. 8-15) (activity index as in Fig. 4). Note rise 
before dawn (ANOVA of last 6 hr: Tunnel, P<.01; Activity, P •= .05) 
and before dusk (Tunnel, P<C-001 ; Activity, P<.001). C) Three workers, 
each housed singly in a separate recording assembly; one of the three is 
based on 1 day of records (Mar. 10-11), another on 2 days (Mar. 30- 
Apr. 1), and the third on 4 days (Mar. 30-Apr. 1 & Apr. 11-12), but 
only the average was used for each hour where there was more than 1 
day of records; thus N = 3 ants. D) Same group of 10 workers as in 
Fig. 4; Activity, N — 3-4 days (Mar. 10-15) (activity index as in Fig. 
4) ; Arena, N — 4-5 days (Mar. 9-15). 
