Sex ratio and sexual dimorphism in Formica exsectoides, the Allegheny mound ant (Hymenoptera : Formicidae)

Citation
Hc. Rowe et Cm. Bristow, Sex ratio and sexual dimorphism in Formica exsectoides, the Allegheny mound ant (Hymenoptera : Formicidae), GT LAKE ENT, 32(3), 1999, pp. 207-218
Citations number
38
Categorie Soggetti
Entomology/Pest Control
Journal title
GREAT LAKES ENTOMOLOGIST
ISSN journal
00900222 → ACNP
Volume
32
Issue
3
Year of publication
1999
Pages
207 - 218
Database
ISI
SICI code
0090-0222(199923)32:3<207:SRASDI>2.0.ZU;2-B
Abstract
We excavated 66 mounds from 6 populations of Formica exsectoides in Michiga n jack pine, collecting sexual caste pupae for sex ratio estimates and meas urement of dimorphism. Reproductive caste brood was present in only 37 of t he 66 mounds, and presence of reproductive caste brood was associated with larger mound surface area. Females were heavier than males, but did not dif fer from males in energy density. Sexes did not differ in timing or rate of development. Sex ratio estimates based on individual mounds ranged from 1. 0 (all male) to 0.08 (female-biased). Four of the six study populations wer e strongly male-biased, while sex ratio estimates for the remaining populat ions did not; differ from equal investment. While this interpopulation vari ation may be caused by genetic factors, the equal investment populations we re located in or near patches of clear-cut forest, suggesting that environm ental impacts should be investigated.