title: Variation in mating systems of salamanders: mate guarding or territoriality?
abstract: Two of the most common mating tactics in vertebrates are mate guarding and territoriality, yet much of the research on these strategies has focused on mating systems in birds, despite novel insights gained from studying less traditional systems. North American stream salamanders that comprise the Eurycea bislineata complex represent an excellent nontraditional system for comparing mating strategies because these species exhibit a continuum of male morphologies, diverse habitat associations, and various potential mating strategies. We studied two species within this complex that exhibit the extremes of this continuum, Eurycea aquatica (robust morph) and Eurycea cirrigera (slender morph). The larger head in males of E. aquatica is due to larger musculature around the jaw and may be associated with aggressive behavior. Therefore, we hypothesized that the robust morphology exhibited by males of E. aquatica provides benefits during either territorial defense or mate defense and that males of E. cirrigera would not exhibit aggression in either scenario. We found that neither species exhibited aggressive behavior to defend a territory. However, in the presence of a female, males of E. aquatica were significantly more aggressive toward intruding males than were males of E. cirrigera. Therefore, mate-guarding behavior occurs in E. aquatica, and the enlarged head of males likely aids in deterring rivals. This is the first demonstration of mate-guarding behavior in a plethodontid, the most speciose family of salamanders.
authors.affiliation: Department of Biological Sciences, 331 Funchess Hall, Auburn University, Auburn, AL 36849, United States; Department of Department of Biological Sciences, East Campus Science Center, Lock Haven University, Lock Haven, PA 17745, United States. Electronic address: jenneymd@gmail.com.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Deitloff
authors.affiliation: Department of Biological Sciences, 331 Funchess Hall, Auburn University, Auburn, AL 36849, United States; Department of Computer Science, University of Texas at Dallas, Richardson, TX 75080, United States.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Alcorn
authors.affiliation: Department of Biological Sciences, 331 Funchess Hall, Auburn University, Auburn, AL 36849, United States; Department of Biology, Pennsylvania State University, University Park, PA 16802, United States.
authors.forename: Sean P
authors.initials: SP
authors.lastname: Graham
mesh_terms: D000374:Aggression / Q000502:physiology*; D000818:Animals; D005260:Female; D008297:Male; D052586:Mating Preference, Animal / Q000502:physiology*; D013731:Territoriality; D014562:Caudata / Q000502:physiology*
keywords: Aggression; Eurycea; Morphology; Reproduction; Sexual selection