Abstract: Young ant queens face two conflicting challenges. First, they must fly to mate, disperse and locate a nest site. Second, they must found a new colony and raise their first workers with their own nutrient reserves. The Found or Fly (FoF) hypothesis posits a fitness tradeoff between colony founding success and flight ability, mediated through abdominal nutrient loading of young queens. It proposes that though heavier abdomens increase survival during the founding period, they do so at the expense of a queen's ability to mate, disperse, and survive the mating flight. We evaluate FoF by characterizing the flight morphology of a common Neotropical year round breeder, Azteca instabilis (Smith, 1862). Abdomen mass varied among queens independently of body size and throughout the year. Heavier abdomens adversely impacted three metrics of flight ability: flight muscle ratio, wing loading and drag. These patterns are consistent with FoF. FoF links reproductive demands, morphology and dispersal ability, and provides a quantitative framework for understanding dispersal variation across the ants. FoF provides insight into several areas of ant ecology and evolution, including alternative reproductive strategies, sexual dimorphism and invasions.