It may be Friday the 13th, but this article is talking about some lucky ants. Canopy ants, in particular. Ants that forage in trees exhibit a high level of ecological dominance, and ants are usually the most conspicuous organisms running around on tree trunks and branches, especially in tropical forests. This begs the question: Why? Dr. Terry McGlynn and Erica Parra, in a paper published last year, set out to address this question.