Three queen morphs with alternative nest-founding behaviors in the ant, Temnothorax longispinosus

• Published in: Insectes sociaux Vol. 53; no. 4; pp. 480 - 488
• Main Author: HOWARD, K. J
• Format: Journal Article
• Language: English
• Published: Basel Springer 01-12-2006
• Subjects: Animal ethology; Biological and medical sciences; Formicidae; Fundamental and applied biological sciences. Psychology; Protozoa. Invertebrata; Psychology. Psychoanalysis. Psychiatry; Nesting; Size polymorphism; ants; Formicidae; Insecta; dispersal; Social insect; Formicoidea; Dispersion; Reproduction; reproductive strategies; Queen insect; Temnothorax longispinosus; Arthropoda; Colony foundation; Strategy; Intraspecific comparison; Behavior; Hymenoptera; Invertebrata; Morphometry; Aculeata; Polymorphism
• ISSN: 0020-1812; 1420-9098
• DOI: 10.1007/s00040-006-0905-6

In many ant species, multiple modes of found-ing new colonies occur in the same population. These modes include dependent founding, independent founding by haplometrosis (single queen), and independent founding by pleometrosis (multiple queens). In several cases, a dimorphism in queen size has been found, such that each morph specializes in a particular nest-founding behavior. I investigated queen size in the ant Temnothorax longispinosus in several southern Wisconsin populations and found three distinct queen morphs: small queens with very low fat content and short wings, large queens with low fat and long wings, and large queens with high fat and very long wings. Several traits associated with founding behavior correlated with these queen sizes. Small queens were produced in lower numbers, were more common in polygynous nests, and returned to the nest in higher proportions than both large queen morphs. The size ranges and fat levels of each queen morph were similar to those of other species that specialize in either haplometrosis (very large, high fat), pleometrosis (large, low fat), or dependent founding (small and low fat). However, there was extensive overlap in several of the founding behaviors, suggesting that the morphs in these populations have some flexibility in founding behavior. The queen morphs in these populations of T. longispinosus may resemble early stages in the evolution of more specialized dispersal polymorphisms found in other ant species.