Presentation on theme: "Territoriality: Costs and conditions The decision to take and/or keep a resource is a function of: Cost is in resource defense Personal damage and energy."— Presentation transcript:
Territoriality: Costs and conditions The decision to take and/or keep a resource is a function of: Cost is in resource defense Personal damage and energy loss Less time spent in predator vigilance Lost foraging time Benefits: Consistently more and better food Less effort to maintain a territory then to acquire one. Yarrows Spiny Lizard: Territoriality is seasonal Controlled by hormone levels
Yarrows Spiny Lizard: Elevated Testosterone in non territorial seasons decreased: Feeding time/effectiveness Lifespan due to starvation Controls suffered too Feeding treated animals corrected for effects
Territoriality benefit: More food
Territoriality benefit: More food = Healthier males Able to leave wintering grounds sooner Establish ownership of resources at mating grounds sooner
Territoriality: Costs vs benefit: Conditional strategies: Male golden winged sunbirds will defend flower patches but only if there is a net caloric gain in doing so.
Costs per/hour: Foraging = 1000 calories Resting = 400 calories Defense =2000 calories Territoriality: When to defend
The adaptive value of allowing satellites in your territory Pied wagtails are conditionally territorial and on occasion will defend rich territories in owner-satellite teams.
King of the hill: Why its easier to own than to acquire
King of the hill: the Speckled wood butterfly Owner always wins territorial conflicts because owning the territory has imparted an advantage: payoff asymetry The value of ownership in this case is that sunning spots increases muscle tempurature which enhances flight capability manuravibility.
King of the hill: The more time on top the stronger Tarantula hawk wasp owners win territorial conflicts but conflict duration increases as a function of time away