Date on Senior Honors Thesis


Document Type

Senior Honors Thesis



Degree Program

College of Arts and Sciences

Author's Keywords

Skototaxis; Ant swimming behavior; Camponotus


Most terrestrial arthropods are helpless in water, and falling from a tree into a flooded forest understory should be especially problematic for small, cursorial organisms like ants. Whereas many species of tropical arboreal ants can tread across the water surface (i.e., swim), less is known of this behavior in temperate forest ants. I tested for swimming ability in various ant species collected from tree trunks in Kentucky. Results show that Camponotus pennsylvanicus, and C. nearcticus, are strong swimmers (operationally defined as directed motion at speeds > 3 body lengths per sec.), while Crematogaster ashmeadi, and Monomorium minimum tend to struggle and become trapped at the water surface. Laboratory studies suggest that the ants direct their swimming toward dark objects (i.e., skototaxis), presumably to locate tree trunks or other emergent structures. Collectively, these results suggest that living and foraging well above the ground poses special challenges for cursorial animals.