1984] 
Gordon — Pogonomyrmex badius 
263 
the second. Marked nest maintenance workers were probably in 
transition to patrolling during the first observation period. Later, 
nest maintenance ants became patrollers, as shown. 
The results of Porter and Jorgensen ( 198 1 ) for P. owyheei suggest a 
schema similar to the one of Figure 1 . Foraging, for these authors, 
may include midden work, patrolling, conveningand foraging as they 
are defined in Table 3. By examining the behavior of foragers in more 
detail, the present study indicates the existence of at least one group 
of ants older than those engaged in food retrieval: ants doing both 
midden work and patrolling. The relationship between these two 
activities will be addressed in a subsequent paper(Gordon 1984b). It 
would be interesting to examine role behavior in field colonies of P. 
badius using the classification of behavior employed in the present 
study. 
I do not attempt in this study to describe division of labor in the P. 
badius colony as a whole, because the behavior of interior workers is 
not considered. But the results raise several questions about age 
polyethism in exterior workers. First, there appear to be two groups 
of exterior workers in the colony. Ants of one group first do conven- 
ing and then foraging, while ants of the other first do nest mainte- 
nance and then midden work and patrolling. It appears that ants 
from either group may then become conveners. What determines to 
which group an ant will belong? The possibility that these groups 
correspond to different sizes of workers within the minor subcaste 
was examined, but I found no such relationship. Second, exactly how 
long do individual ants remain in each of their roles? For a long-lived 
species like P. badius, the answer to this question awaits a marking 
technique better than the one used in this study. After about four 
months, some of my marked ants were seen to have most of the paint 
chipped off. 
The unresolved questions in this study are part of a larger one: how 
is the distribution of workers into different roles regulated? There is 
considerable evidence that individuals are channelled into particular 
roles according to the current needs of the colony (e.g. Meudec and 
Lenoir 1982, Lenoir and Ataya 1983, Wilson 1983). To answer the 
questions raised by this study, we must come to understand the 
system by which the colony assesses and predicts what needs to be 
done. 
