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[Vol. 94 
Table 2. Pupae acceptance by slave species workers (F. gnava) 
Surviving Pupae 
Colony 
# Workers 
Same 
Different 
FG2 
81 
24 
25 
FG3 
85 
24 
23 
FG4 
276 
23 
23 
FG5 
323 
24 
22 
FG6 
500 
25 
25 
FG7 
238 
24 
22 
FG8 
400 
23 
23 
FG9 
174 
21 
24 
FG10 
250 
23 
24 
FG1 1 
115 
23 
24 
FG12 
112 
25 
24 
Correlated groups t = 0.19; df = 10; NOT SIGNIFICANT 
“different” conditions for both species of Formica (t-test for corre- 
lated groups, F. schaufussi: t = 1.25, df = 6; F. gnava: t = 0.19, 
df = 10). Free-living Formica workers of these species treat alien 
conspecific pupae as their own. With the exception of F. gnava 
colony FG10, in which two pupae of the “same” condition were 
found in their “garbage” pile, pupae were not discarded intact from 
any nest and none became moldy. The number of pupae that disap- 
peared was fairly constant in all groups despite differences in colony 
size. Possibly the lost pupae were defective or diseased, which might 
be expected to occur with a similar frequency in all groups. 
Experiment 2: Intraspecific Pupae Exchange 
(Free-Living vs. Enslaved Formica) 
Methods and materials 
Three laboratory colonies of P. lucidus with F. schaufussi slaves 
and six free-living laboratory colonies of F. schaufussi were used in 
this experiment, which was conducted in January and February of 
1985. Each colony was handled as in the previous experiment, with 
queen and workers being placed in a new nest. P5, a large P. lucidus 
colony, was divided into two parts: P5(l), with a ratio of slaves to 
raiders of approximately 10:1, and a total of 459 ants; and P5(2), 
with a ratio of 1:1 and a total of 200 ants. After a 5-day period of 
isolation, 25 F. schaufussi pupae from different colonies were added 
to each. Five days later, the surviving pupae and callows were 
counted. 
