establishment despite the presence of otherwise dominant species (Longino 1989, Palmer

et al. 2002).

 Characteristics of the host plants and the resident ant colonies change over time as

the plant develops and the ant colonies grow, senesce or are replaced by other species

(Vasconcelos and Casimiro 1997, Young et al. 1997, Alonso 1998, Itino and Itioka 2001,

Del Val and Dirzo 2003). The mechanisms listed above are rarely manifested at one

point in time at a single locale, but rather promote species coexistence at larger spatial

and temporal scales (Young et al. 1997; Alonso 1998; Yu et al. 2001, 2004). The early

ontogeny of myrmecophytes may be particularly important for species-sorting of ant

occupants (Davidson et al. 1989, Vasconcelos and Davidson 2000, Palmer et al. 2002).

A comprehensive understanding of ant species coexistence in ant-plant symbioses

therefore must encompass both differences in the life history strategies of the ant species

and the temporal dynamics of the symbiosis.

 Cordia alliodora is a neotropical myrmecophytic tree inhabited by several ant

species, including both specialists and stem-nesting generalists. Although C. alliodora

has an extensive geographic range and is often locally abundant, little community-level

research has been conducted on the ants that inhabit this myrmecophyte (but see Longino

1996 and Tillberg 2004). Here I describe patterns of ant occupation in C. alliodora

during the course of the host plant's ontogeny from sapling to young mature tree.

Specifically, I investigated the following questions: 1) How does ant community

composition change with plant age? 2) Is there spatial variation in ant species occupancy?

3) Are there interspecific differences among ant species in colony founding and