1983] 
Gordon — Pogonomyrmex badius 
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between activities were used as observation variables (Table 2, 
middle). The results (Figure 1 for foraging, and Table 2 for the other 
activities) show that the activities may be ranked as follows, accord- 
ing to the numbers of ants engaged in each one: Midden work > 
patrolling > convening > nest maintenance > foraging. 
Figure 1 shows the activity rhythms of each of the four study 
colonies. The third manova tested whether some pairs of activities 
are performed by significantly different numbers of ants when the 
activities are compared at particular times (Table 2, bottom). 
Significant differences mean that the rate at which the colony 
invests workers in a particular task depends both on the task and on 
the time of day. The results (Table 2) may be best understood by 
inspecting Figure 1 . For example, keeping in mind that the data are 
log-transformed, activity-time period difference number 4 (Table 2) 
can be stated as follows: The ratio of number of ants doing midden 
work to number convening in time period 1 is significantly greater 
than the same ratio in time period 3. In other words, from TPl to 
TP3 convening increases faster, or has a steeper slope, than does 
midden work. This difference is especially clear in the graph for 
colony 4. 
The overall results in Table 2 lead to the following conclusions 
about slope differences in Figure 1: Convening rises to a peak in 
TP2, increasing more rapidly than midden work, then declines more 
rapidly than either midden work or patrolling. In general, patrolling 
declines throughout the day while nest maintenance increases. The 
fact that activity-time period differences 7, 8, and 9 are not signifi- 
cant indicates that all 4 activities change at about the same rate from 
TP3 to TP4. 
The colony main effect was significant (p > 0.05) for time period 
differences 1, 2, and 4, for activity differences 1, 2, and 3, and for 
activity-time period differences 1, 4, 5, 6, and 10. The date main 
effect was significant for time period difference 3, activity difference 
3, and activity-time period differences 3, 7, 8, and 1 1. 
Mean temperatures of the terraria surfaces are shown in Figure 2, 
as a function of the time of day. 
Discussion 
The behavior of a colony clearly is temporally patterned. It has 
frequently been suggested that, in harvester ants, overall activity 
