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Psyche 
[Vol. 89 
Finally, although we have no direct evidence, we suppose that 
many colonies of these species must originate when a queenright 
portion of a polydomous colony becomes permanently separated 
from the other parts, a process known as “budding”. Incipient nests 
containing only queens and an immature brood seem too rare to 
account for all colony foundation in these species. 
General Discussion 
We can now reconstruct the colony life histories of these species 
in some detail. New colonies of L. longispinosus can be established 
either by a single newly mated young queen (haplometrosis) or by 
two or more such individuals (pleometrosis). New colonies of L. 
ambiguus are established pleometrotically; and it seems likely that 
further research will establish that colonies of this species and of L. 
curvispinosus can be founded either pleometrotically or haplome- 
trotically. Young colonies of these species probably occupy only one 
nest (monodomy). However, as they grow, some colonies of L. 
ambiguus and L. longispinosus come to occupy two or more nests 
(polydomy) among which there can be an exchange of workers, 
brood, and queens. Mature colonies of all three species containing 
one or more fully fertile inseminated queens also sometimes adopt 
additional conspecific queens. Finally, we hypothesize that new col- 
onies can be formed as a result of the break-up of polydomous 
colonies into two or more autonomous units (budding). 
When considering these facts, one immediately notes a large 
amount of behavioral variability. Although we do not yet know 
whether any individual queen is potentially capable of doing more 
than one thing, young queens as a class can either join an estab- 
lished colony, found a new colony alone, or found a new colony in 
the company of one or more other queens. Colony life cycles and 
demographies are also variable. A colony can apparently have one 
or more queens at almost any stage of its development and can 
occupy one or more than one nest when mature enough to produce 
reproductives. Such behavioral variability is unusual, and its adap- 
tive significance is obscure. Thus, the behavioral ecology of these 
three species offers many opportunities for empirical and theoretical 
analysis. 
Two problems are particularly salient. First, we have demon- 
strated that some queenless nests are parts of polydomous colonies; 
