Sociobiology

Sociobiology is any kind of interaction between two or more animals Usually intraspecific

Competitive Behavior Usually represents contests for resources Agonistic behavior involves threatening and submissive behavior, often ritualized

Agonistic behavior usually does not result in the death of either animal Agonistic behavior may determine rights to food, mates, or territory

In animals where social dynamics are important reconciliation behavior has been seen

Can be “despotic” or “linear” Dominance hierarchy “Pecking order” Can be “despotic” or “linear”

In the spotted hyena females are dominant over males Hierarchy is nepotistic, offspring of high ranked females automatically outrank lower ranked females

Territoriality An area of land that is claimed by an individual Usually all other conspecifics (members of the same species are excluded from the territory Territories vary in size based upon the size of the animal and what its needed for

Territory vs Home Range Home ranges are the area where animals roam but are not actively defended

Territories may be claimed by a variety of means, the most common are: Claiming territory Territories may be claimed by a variety of means, the most common are: Aural– Bird song Olfactory – scent marking

Mating behavior Observations http://www.youtube.com/watch?v=cBX8hWui HTk (3:55)

Reproductive behavior includes seeking, choosing, and competing for mates, as well as caring for offspring.

Courtship is any behavioral patterns that lead to mating The purpose of courtship is to identify conspecifics and to identify mates that are ready to reproduce

Parental Investment Much of mating behavior stems from the unequal investment males and females put into their offspring

In most systems the male (sperm creators) will gain an evolutionary benefit by having multiple mates In most systems the female (egg creators) will gain an evolutionary benefit by having a single high quality mate

Female choice results when females screen out low quality males and only mate with high quality males

Promiscuity, Monogamy, Polygamy Promiscuity – no pair bonds Monogamy – one male/one female, lasts through at least one mating season Polygamy – any system where lasting relationships are not monogamous

Polygyny – One male, multiple females Polyandry – One female, multiple males Polygynandry – Any given female may have multiple male partners, any given male may have multiple female partners.

Factors influencing mating systems Amount of care required for offspring (promotes monogamy) Certainty of paternity (promotes monogamy) Capability to make more offspring

Communication may be visual, auditory, chemical, tactile Communication occurs when a sender produces a signal that is detected by a receiver Communication may be visual, auditory, chemical, tactile

Pheromones Communication done through odor (chemical signals) http://www.youtube.com/watch?v=D5uiSyFBpgM

Honeybee dance Karl von Frisch Close food sources result in a “round dance” Long distance = waggle dance. Angle relative to vertical surface = angle relative to sun. More waggles = more distance.

http://www.youtube.com/watch?v=-7ijI- g4jHg