Animal Behavior

occurs when an animal lays claim to an area and defends it against other animals

members of an aggressively organized group coexist with one another within one territory

Despotism

because of communication and recognition

• Xenophobia
• Strong Leadership Means Peace
• The Will to Power
• Nested Hierarchies
• Social Inertia

• Disease
• Competition for Mates
• Competition for Resources

• Get food
• Get shelter
• Get mates
• Less stress
• Grooming

• Less food
• Reproduce less often
• Poorer nesting sites and shelter

• Consequences of being subordinate
• - emigration
• - "sneak copulations"
• - benefits of being in a group

• - adults are dominant over juveniles
• - bigger animals are usually dominant over smaller animals
• - healthy animals are dominant over sick animals
• - males are dominant over females
• - animals are most dominant on their own territories
• - accidents play a role
• - intensity of status signals

• Slavery, Kignapping, Killing
• - wolfs

Hierarchies

• any defended area...contra Home Range
• - recognized 2,300 years ago by Aristotle (2 Falcons will not occupy the same area..) (Formalized by Eliot Howard 1920)

refers to all space used by an animal

• - To control critical resources (e.g. for breeding): often advantageous to control somewhat more than the minimum amount
• * male might be able to attract >1 female or a higher quality female (polygyny threshold model)
• - To reduce predation (reduces chance of community becoming a popular hunting area)
• - As a sexual advertisement
• - To help with mate-guarding
• - NOT to control popoulation size (Wynne-Edwards, Ardery)

• a resource attribute
• - consider how large a territory ought to be staked out and maintained

Resource quality and spatial distribution ("patchiness")

• The optimal size of territory to defend shrinks
• - richer you get the more you can afford to relax (you no longer need to be desperate)

• - animals move to position conspecifics between themselves and predators
• - if predators take nearest animal, moving to center benefits individual
• - result: form tight groups because each individual selfishy seeks middle
• - forming groups does NOT imply cooperation
• - each individual may be selfishly for its own benefit

Several prey can flee in unpredictable directions

• - Birds search for a clumped source of food web more successful in groups of four than in pairs or singly
• - different species can learn where food is from one another

Passive: Thermoregulation, Kin related benefits, grooming, etc.

• Coordinated Foraging
• - makes more food availabe to be hunted
• - reduces path overlap
• - allows species to compete better for food with other competing species
• - enables unsuccessful individuals to learn locations of new food resources from successful individuals in the group
• - reduces energy costs or risks per individual or permits the taking of larger prey

Birds move through a field they flush out insects so all can eat or some leader species (large mammal) disturbs foliage causing insects to fly

• reduces energy costs or allows animals to take larger prey
• - weight of four social carnivores and weight of prey species they are able to kill
• - hyena 100lbs/ 660 lbs
• - lion 240 lbs/ 2000 lbs
• - wolf 80 lbs/ 800 lbs
• - hunting dog 35 lbs/ 550 lbs

• Signal CAN be mutually beneficial, but should always, on average, benefit the signal sender
• - corollary: it may benefit the receiver or it may exploit the receiver ruthlessly, or it may have utterly trivial value to the receiver
• - viewed as coevolutionary 'arms race', in which all players play both roles (signal sender and receiver-- frequently)

sound, light, touch, electrical, and chemical

• Energy source = usually sun (occasionally bioluminescence)
• Coding Variables
• - Brightness (surface refelectivity)
• - Color (uv of light NOT absorbed)
• - spatial patternine of the above two
• Properties
• - short duration
• - closed channel (receiver must have eyes open & be facing signaler)
• - Long range
• - Light rays don't bend; can be blocked

• Energy source = Internal
• Coding Variables
• - pitch (= frequency = wavelength)
• - loudness (energy level)
• - temporal patterning is very important
• Properties
• - short-lived
• - sound attenation
• - channel continuously open
• - can circumnavigate objects (esp. long-wave)
• - localizable

• Energy source = Pheromones = like hormones between individuals. Universal
• Properties
• - Channel open
• - Amplification principle: tiny investment can elicit expensive response
• - Enormous potential range (wind-borne)
• - fantastic specificity
• - flaw: achingly slow

• - live in social groups called clans
• - clan members defend a territory and hunt in groups
• - femalse are dominant members of the clan ( clear dominance hierarchy)

penis sniffing

• Females penis
• - enlarged clitoris

• - 10-20% of females die giving birth first time and 60% of first born pups die
• - pseudopenis must provide big selective advantage to balance this

• - hormones increase aggression in females (increase social status, and access to food)
• - sniffing appears to enhance cooperation among hyenas (communication)
• - sniffing enable dominants to monitor hormonal status of other females
• - dominant benefit: know if challenged
• - subordinates benefit: allowed to remain in pack

complex traits evolve from less complex ones as a result of a long sequence of small developemental changes

• - natural selection can only operate on the material available to it
• - evolutionary intermediates must be improvements over what preceded them
• - intermediate structures can have different functions to their current ones, but should be useful in some way

• - gill plates, retained in the adult, act as sails allows the insect to skim over the surfact of the water
• - increaseing wing size would increase skimming speed
• - beating wings would increase speed still further so adding musculature would be favored by selection

- display signals to be expensive and difficult for smaller/ weaker individuals to imitate.

mistake made because environment has changed. response once adaptive.

• response adaptive on average, but sometimes expolited
• - risk outweighed by benefits.

• 1. Common interest
• 2. Handicap/cost
• 3. Index of quality (uncheatable signals)

• a form of non-random mating
• - selection that arises when individuals of one sex, usually males, gain an advantage over others of the same sex in obtaining mates
• - targets loci that code for mate choice traits and changes allele frequencies

• - acts on males much more strongly than females
• - females usually invest much mroe in their offsprint than do males
• - females prefer males with certain characteristics

• - female fitness is limited by an ability to gain the resource required to produce egges and rear young
• - male fitness is limited by the ability attract mates

• - fighting between males
• - attract females

• - intrasexual (fighting)
• - intersexual (epigamic)- attract females

females must show a sexual attraction for males that have certain secondary sexual characteristics (ornaments, behaviors, etc.)

• Males: possessing a character preferred by females is clear - he gets to mate more often
• Females: mating with a male that has that character - character is heritable = more sons = more offspring

• Female preference and male attractiveness evolve together
• - Females that mate iwth males that do not have this character will produc less sexy sons and therefore their choice will be lost over time

• original character must have been some marker of some other characteristic that increases male fitness
• - once that characteristic become linked to greater male fitness, ti become established simply for its attractive properties

more than one mate

male mates with more than one female

female mates with more than one male

• males gain access to female by controlling resource stahat are vital to females
• - ex. bullfrogs ( with the best territories get the most mates)

• males gain access to females by directly defending them against rivals
• - ex. elephant seals (most dominant gets the most mates)

• No male defense of females of resources
• - males set up a dominance hierarchy and females choose them
• - explosive breeders (short breeding period) (Cascades Frog)
• - leks (communal display area) (Prairie Chicken)

Traditional Combat or Indirect

• Scorpionfly
• - female eats while copulating with male
• - copulation last as long as food lasts

• Scorpionfly
• - secrete hard salivary mass/ pheromone induces females to mate
• - disperse pheromone on deat insect after eatin dead insect female mates
• - Forced copulation (rape) : male rushes female

• - attack and get insect to offer to potential female mate
• - steal food from rival male to give to female
• - turn into female, entice male to give you food and fly away and give it to female (transvestite blowflly strategy)

• Female coyness & mate choice
• - males usually must display to females
• - males ' salesmanship' (display, provide food, make a nest, etc.)
• - females are 'coy'

• - correct species
• - correct sex
• - sexually mature
• - good male genes; survivorship, reproductive ability, complimentarity of genes
• - willingness in male to care for offspring
• - ability to invest
• - complimentarity of parental attributes

• Focus on stimuli that trigger and support behavior
• - genetic, physiological, neural, envrionmental

• Fixed action pattern
• - unchangeable sequence of unlearned, innate behaviors
• - once initiated, usually carried to completion
• - sign stimulus
• - external sensory stimulus

• Hormones and Behavior
• - Organization: permanentmorph change, in early development, critical period
• - Activation: during puberty, changes due to increase, androgens or estrogens

• Physcial Environment ( Day length, temperature)
• Social Environment (Social cues can cause hormonal changes)

• - exposure to androgen can masculinze females
• masculine: aggressivenss, attacks, mounting and intromission, little parental behavior
• feminine: non-aggressive, attractiveness to males, exhibit parental behavior

• part of the Nervous system
• - samples the environment for information

• part of the nervous system
• - produces action

• - organs produce class of proteins called hormones
• - delivered passively via the circulatory system - relatively slowly

organizational & activational effects

• - occur very early
• - influence a subset of neurons
• - shape adult behavioral repertoire a permanent menu change

• - require immediate presence of key hormone for the sensitive neurons to function normally. to 'turn on'
• - themporary (short term) menu change

• radioimmunoassay
• - measures concentrations of hormones

Basic predation = that (T) should be high when males are most aggressive with each other & vice versa

bonded for life with no replacement, even if mate dies

• Natural: reproductive success, rivals = both sexes
• Sexual: mating success, rivals = same-sex

• one sex becomes a restricted resource for the other (because it has higher costs associated with mating), access to it "limits" what the other sex can achieve
• limiting sex: female
• limited sex: male

any effort toward one offspring that increases the change of that offsprins survival at the cost of the parents ability to invest in other offspring (Trivers)

can be observed

males probability of bieng genetically related to offspring is nearly always lower that of female

a focal male can either remian with his current mate and contribute to the raising of her young (STAY) or he can go off and seed a second mate (DESERT)

one parent departs before the other one has equivalent opportunity, it puts the partner in a cruel bind (depending on the brood's needs)

• Most animals -- no parental care
• 1. value for staying
• - precocial young, altricial young
• 2. value for deserting
• - often hinges on availability of high-quality alternative mates