Thermal Influencein Adaptation of Ants (Hymenoptera: Formicidae) in Rock Canyon: Provo, Utah, U.S.A.

William N. Barron, 606 West 1720 North Apt. 224, Provo, Utah 84604 Email:

Abstract

The behavior of ants (Formicidae) is affected by thermal conditions, but more research is required before we can discern between the adaptation of populations to temperature changes and selection for more tolerant individuals. Experiments will be conducted in Rock Canyon with local ants to show that their behavior will change with environmental temperatures without the need of natural selection in successive generations. Ant colonies from various areas will be identified and counted, and on a daily basis air temperature and soil depth will be measured. Abiotic values will be plotted against population density.

Introduction

Ants are a family of insects that have been biologically successful (Walters and Mackay 2003). Formicid colonies are found worldwide in a variety of environments. Although their distribution makes them a popular subject of study(Floate and Skovgaringrd 2004), the delineation between their ability to adapt to different thermal conditions and the need of selection for higher temperature tolerance is still unclear. Ants cannot stand temperatures greater than 50˚C (Walters and Mackay 2003), and some larvae are susceptible to death at temperatures of-2.5˚C (Floate and Skovgaringrd 2004). Because soil temperature can be correlated to foraging activity by as much as 63% (Vogt et al. 2003), research will be conducted with ant hills to establish activity ranges of individuals from one generation.

Methods and Materials

Ant colonies will be located and identified with an orange flag within Rock Canyon Park in Provo, Utah. The number of ants on the surface of each colony will be recorded daily and their species determined using a dichotomous key. One temperature reading will be taken daily at each site for four weeks. The reading will be taken each day at the same time at the soil depth where the ants are found as the soil and air temperatures may be different. Changes in the number of ants from day to day will indicate an increase or decrease in activity. Weather conditions such as rain, snow or site disturbance will also be recorded. Statistical tests and analyses will be used to show significance between physical activity and temperature.

Literature Cited

Floate, K.D. and H. Skovgaringrd. 2004. Winter survival of nuisance fly parasitoids

(Hymenoptera :Pteromalidae) in Canada and Denmark. Bulletin of Entomological

Research 94:331-340.

Vogt, J. T., W. A. Smith, R. A. Grantham, and R. E. Wright. 2003. Effects of temperature and

season on foraging activity of red imported fire ants (Hymenoptera : Formicidae) in

Oklahoma. Environmental Entomology 32:447-451.

Walters, A.C. and D. A. Mackay. 2003. An experimental study of the relative humidity

preference and survival of the Argentine ant, Linepithema humile (Hymencptera, Formicidae): comparisons with a native Iridomyrmex species in South Australia. Insectes Sociaux 50:355-360.

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