2 What is behavior? Behavior everything an animal does & how it does it response to stimuli in its environmentinnateinherited, “instinctive”automatic & consistentlearnedability to learn is inherited, but the behavior develops during animal’s lifetimevariable & flexiblechange with experience & environment
3 Why study behavior? Evolutionary perspective… part of phenotype acted upon by natural selectionlead to greater fitness?lead to greater survival?lead to greater reproductive success?
4 What questions can we ask? Proximate causesimmediate stimulus & mechanism“how” & “what” questionsUltimate causesevolutionary significancehow does behavior contribute to survival & reproductionadaptive value“why” questionsmale songbirdwhat triggers singing? how does he sing? why does he sing?Proximate cause questionsMale songbirds sing during the breeding season as a response to a high level of testosterone which binds to hormone receptors in the brain & triggers the production of song.Ultimate cause questionsThe male sings to defend territory from other males & to attract a female with which to reproduce. This is the evolutionary explanation for the male’s vocalization.The red–crowned cranes, like many animals, breed in spring and early summer. A proximate question about the timing of breeding by this species might be, “How does day length influence breeding by red–crowned cranes”? A reasonable hypothesis for the proximate cause of this behavior is that breeding is triggered by the effect of increased day length on an animal’s production of and responses to particular hormones. Indeed, experiments with various animals demonstrate that lengthening daily exposure to light produces neural and hormonal changes that induce behavior associated with reproduction, such as singing and nest building in birds.In contrast to proximate questions, ultimate questions address the evolutionary significance of a behavior. Ultimate questions take such forms as, Why did natural selection favor this behavior and not a different one? Hypotheses addressing “why” questions propose that the behavior increases fitness in some particular way. A reasonable hypothesis for why the red–crowned crane reproduces in spring and early summer is that breeding is most productive at that time of year. For instance, at that time, parent birds can find ample food for rapidly growing offspring, providing an advantage in reproductive success compared to birds that breed in other seasons.Courtship behavior in cranes what…how… & why questions how does daylength influence breeding? why do cranes breed in spring?
5 Evolutionary perspective Adaptive advantage?innate behaviorsautomatic, fixed, “built-in”, no “learning curve”despite different environments, all individuals exhibit the behaviorex. early survival, reproduction, kinesis, taxislearned behaviorsmodified by experiencevariable, changeableflexible with a complex & changing environment
6 male sticklebacks exhibit aggressive territoriality Innate behaviorsmale sticklebacks exhibit aggressive territorialityFixed action patterns (FAP)sequence of behaviors essentially unchangeable & usually conducted to completion once startedsign stimulusthe releaser that triggers a FAPattack on red belly stimuluscourt on swollen belly stimulus
7 Fixed Action Patterns (FAP) Digger waspegg rolling in geeseDo humans exhibit Fixed Action Patterns? This question was addressed by Irenaeus Eibl-Eibesfeldt and Hans Hass who worked at the Max-Planck-Institute for Behavioural Physiology in Germany. They created a Film Archive of Human Ethology of unstaged and minimally disturbed social behaviour.They filmed people across a wide range of cultures with a right-angle reflex lens camera i.e. the subjects did not realize that they were being filmed because the camera lens did not appear to be pointing at them! Eibl-Eibesfeldt has identified and recorded on film, several human Fixed Action Patterns or human 'universals' e.g. smiling and the "eyebrow-flash"Eibl-Eibesfeldt took these pictures of a Himba woman from Namibia (SW-Africa). She shows a rapid brow raising (between the second and third still images) which coincides with raising her eyelids. Because all the cultures he examined showed this behaviour, Eibl-Eibesfeldt concluded that it was a human 'universal' or Fixed Action Pattern.Some Sphex wasps drop a paralyzed insect near the opening of the nest. Before taking provisions into the nest, the sphex first inspects the nest, leaving the prey outside. During the sphex's inspection of the nest an experimenter can move the prey a few inches away from the opening of the nest. When the sphex emerges from the nest ready to drag in the prey, it finds the prey missing. The sphex quickly locates the moved prey, but now its behavioral "program" has been reset. After dragging the prey back to the opening of the nest, once again the sphex is compelled to inspect the nest, so the prey is again dropped and left outside during another stereotypical inspection of the nest. This iteration can be repeated again and again, with the sphex never seeming to notice what is going on, never able to escape from its genetically-programmed sequence of behaviors. Douglas Hofstadter and Daniel Dennett have used this mechanistic behavior as an example of how seemingly thoughtful behavior can actually be quite mindless, the opposite of human behavioral flexibility that we experience as free will“When a gray goose, sitting on its nest, sees an egg that has rolled out of the nest, it reacts in a characteristic fashion. It extends its head toward the egg and then, keeping its head and neck pointed toward the egg and its eyes fixed upon it, stands up and slowly steps forward to stand on the rim of the nest. Next the goose bends its neck downward and forward so that the egg rests against the underside of the bill. It then proceeds to roll the egg back into the nest by shoving it back between its legs, using the underside of the bill. At the same time that this movement of the head and neck is taking place in the sagittal plane, the goose performs side to side movements of the head which have the effect of balancing the egg against the under side of the bill.”The eyebrow flash is a universally recognized unconscious social signal, wherein a person, wishing to approach another whom they recognize and are preparing for social contact, raises their eyebrows for approximately one-sixth of a second. People generally return an eyebrow flash, unless it was given by someone whom they do not know, or someone who looks away immediately after. The message must be interpreted in context. Psychologists and sociologists say that eyebrow raising can be a reaction to fear or surprise. Do humans exhibit Fixed Action Patterns?The “eyebrow-flash”
8 Supernormal Stimulus Responding more to a larger sign stimulus Herring gulls have no song, but have a complex system of anywhere from 8 to perhaps 15 calls; two are used by nestlings and another three are used only by breeding adults. Various calls serve to identify returning partners, demonstrate aggression, warn the colony of predators, and to dispute territory with neighboring gulls. When males are disputing territory, they may pull at grass with their beaks as part of their demonstration. Chicks begin making begging calls to demand food upon hatching; the call grows more intense as they grow and by 5 weeks of age, a chick begs by lifting its head with each peep and holding its head hunched against its body. When chicks are pursued, they emit a shrill waver. The begging call and shrill waver exhibited by chicks are both similar to noises that adult gulls make. Chicks also peck at the red spot on their parent's bills in order to stimulate food regurgitation.does lipstick create a supernormal stimulus in humans?
9 Innate: Directed movements Taxischange in directionautomatic movement toward (positive taxis) or away from (negative taxis) a stimulusphototaxischemotaxisKinesischange in rate of movement in response to a stimulusThe sow bugs become more active in dry areas and less active in humid areas. Though sow bugs do not move toward or away from specific conditions, their increased movement under dry conditions increases the chance that they will leave a dry area and encounter a moist area. And since they slow down in a moist area, they tend to stay there once they encounter it.In contrast to a kinesis, a taxis is a more or less automatic, oriented movement toward (a positive taxis) or away from (a negative taxis) some stimulus. For example, many stream fish, such as trout, exhibit positive rheotaxis (from the Greek rheos, current); they automatically swim or orient themselves in an upstream direction (toward the current). This taxis keeps the fish from being swept away and keeps them facing the direction from which food will come.
10 Complex Innate behaviors Migration“migratory restlessness” seen in birds bred & raised in captivitynavigate by sun, stars, Earth’s magnetic fieldsSpotted SandpiperMonarchmigrationBird migration, a behavior that is largely under genetic control. Each spring, migrating western sandpipers (Calidris mauri), such as those shown here, migrate from their wintering grounds, which may be as far south as Peru, to their breeding grounds in Alaska. In the autumn, they return to the wintering grounds.Monarchs that migrate south after summer in North America an be several generations removed from those that flew north the previous year… so how do they know where to go…ancient fly-ways51 sec start
11 Innate & Learning: Imprinting Learning to form social attachments at a specific critical periodboth learning & innate componentsBut how do the young know on whom—or what—to imprint? How do young geese know that they should follow the mother goose? The tendency to respond is innate in the birds; the outside world provides the imprinting stimulus, something to which the response will be directed. Experiments with many species of waterfowl indicate that they have no innate recognition of “mother.” They respond to and identify with the first object they encounter that has certain key characteristics. In classic experiments done in the 1930s, Konrad Lorenz showed that the most important imprinting stimulus in graylag geese is movement of an object away from the young. When incubator–hatched goslings spent their first few hours with Lorenz rather than with a goose, they imprinted on him, and from then on, they steadfastly followed him and showed no recognition of their biological mother or other adults of their own species. Again, there are both proximate and ultimate explanationsKonrad Lorenz
12 Conservation biologists have taken advantage of imprinting by young whooping cranes as a means to teach the birds a migration route. A pilot wearing a crane suit in an Ultralight plane acts as a surrogate parent.Wattled crane conservationteaching cranes to migrateCranes also imprint as hatchlings, creating both problems and opportunities in captive rearing programs designed to save endangered crane species. For instance, a group of 77 endangered whooping cranes hatched and raised by sandhill cranes imprinted on the sandhill foster parents; none of these whooping cranes ever formed a mating pair–bond with another whooping crane. As a consequence, captive breeding programs now isolate young cranes and expose them to the sights and sounds of members of their own species. But imprinting can also be used to aid crane conservationYoung whooping cranes imprinted on humans in “crane suits” have been taught to follow these “parents” flying ultralight aircraft along new migration routes. And importantly, such cranes have formed mating pair–bonds with other whooping cranes.
13 White-crowned sparrow Critical periodSensitive phase for optimal imprintingsome behavior must be learned during a receptive time periodAs a brood parasite, the Cuckoo never learn the song of their species as a nestling. Song development is totally innate.White-crowned sparrowBowlby argued that our need to form attachments was innate and would occur in the sensitive period between the ages of 1 and 3 years.Skin to skin hypothesisKlaus and Kennel (1976) looked at two groups of newly born infants:Group one allowed contact with mother during feeding in the first 3 daysGroup two allowed extended contact with mother lasting several hours a dayOne month later when they returned to the hospital mothers in group two were found to cuddle their babies more and make greater eye contact. The effects were still noticeable a year later.Klaus and Kennel believed that this showed that greater contact led to stronger and closer bond formation between mother and child and provided evidence for the sensitive period.Note: This research led to a change in social policy with hospitals encouraged to room mother and infant together in the days following birth rather than the previous tendency to keep them apart. Also fathers were encouraged to be present at birth so that they too could form an early attachmentimprinting/critical period in humans?Canaries
14 Learned behavior Associative learning learning to associate a stimulus with a consequenceoperant conditioningtrial & error learningassociate behavior with reward or punishmentex: learning what to eatclassical conditioningPavlovian conditioningassociate a “neutral stimulus” with a “significant stimulus”
15 Operant Conditioning Skinner box (2:33 start)Operant ConditioningSkinner boxBF Skinnermouse learns to associate behavior (pressing lever) with reward (food pellet)
16 Classical Conditioning Ivan Pavlov’s dogsconnect reflex behavior (salivating at sight of food) to associated stimulus (ringing bell)
17 Learning: Habituation Loss of response to stimulus“cry-wolf” effectdecrease in response to repeated occurrences of stimulusenables animals to disregard unimportant stimuliex: falling leaves not triggering fear response in baby birds
18 Learning: Problem-solving crowDo other animals reason?chimpanzeeproblem-solvingsea ottertool use
19 Social Behaviors Interactions between individuals develop as evolutionary adaptationscommunication / languageagonistic behaviorscooperationaltruistic behavior
20 Chemical Communication Pheromoneschemical signal that stimulates a response from other individualsalarm pheromonessex pheromones
21 Pheromones human sex pheromone? marking territory Spider using moth sex pheromones, as allomones, to lure its preymarking territoryThe female lion lures male by spreading sex pheromones, but also by posture & movementsThe luring function of sex pheromones is a perfect way for predators to get heir prey without having to work too hard. The spider Mastophora hutchinsoni spreads sex pheromones of moths, using them as allomones. This way he can lure about enough moths to sustain. When the moths fly in, convinced they are about to mate, the spider shoots a sticky ball on wire towards them. As they stick to the ball, he drags them in and eats them.--> INFO on HUMAN PHEROMONES
22 Let’s go to the videotape! Visual Comm.Let’s go to the videotape!Honey bee communicationdance to communicate location of food sourcewaggle danceView Waggle Dance AVI file: waggledance180x135.avi
23 Auditory Communication Vervet monkeysHighly socialPreyed upon by:JaguarsPythonsEagles
24 Tactile Communication Let’s go to fruit flies already…
25 All 4 assist in fruit fly courtship… Can occur via the following stimuli:VisualChemicalTactileAuditory
26 Let’s go to the videotape! Social BehaviorsAgonistic behaviorsthreatening & submissive ritualssymbolic, usually no harm doneex: territoriality, competitor aggression, intrasexual selectionView Lifewire territoriality video: “lizards cost of defending-lifewire.swf”Review setting up a behavior experiment:Let’s go to the videotape!
28 Social Behaviors Cooperation working together in coordination Pack of African dogs hunting wildebeest cooperativelyWhite pelicans “herding” school of fish
29 I would lay down my life for 2 brothers or 8 cousins! Social BehaviorsAltruistic behaviorreduces individual fitness but increases fitness of recipientkin selectionincreasing survival of close relatives passes these genes on to the next generationI would lay down my life for 2 brothers or 8 cousins!How can this be of adaptive value?Belding ground squirrel
30 Foraging BehaviorsInvolve ability to successfully search for, recognize, capture, and eat foodSome forms of foraging are geneticforR vs. forS in fruit flies
31 Foraging Behaviors Optimal foraging Model Cost vs. benefit analysis… which gets most nutrition with least wasted energyNorthwestern CrowBest Height = 5.23 m
32 Mating Behavior 1 MAIN consideration: Depends on: How can I be reproductively successfulWhy does it matter?How does Darwin determine which organism is best suited to survive?Depends on:Attracting matesSelecting a worthy mateCaring for kids
33 Determined by # of Partners Promiscuous- most animal species, mate with many different members of opposite sex (bonanbos & dolphins)Monogamous- 1 male and 1 female mate for a long period of time (swans, wolves, turtle doves)Bonobos, relatives of the common chimpanzee, have won a reputation for promiscuity. Bonobos do not form long-term, sexual partnerships. Rather, they engage in sexual activity with single or multiple partners. They will participate in both hetero and homosexual encounters. In Bonobo society, sex is used for reproduction, but it's also a means of greeting and conflict resolution.
34 Determined by # of Partners Polygamy- 1 male mates with many femalesPolyandry- 1 female mates with many malesSpotted SandpiperMarmosets
35 Number of Partners & Baby Indy Determine Dad’s Investment… Monogamous relationships yield 2 nurturing parents:~90% birds… why?Fitness means passing on DNA…To ensure this happens both parental birds must provide food and protectionNEEDY BABIES!!!
36 Usually when dad can’t be certain he’s the father or is no longer needed… Little/no investmentTrue in most mammalsTrue in most animals periodDad’s goal = fitness
37 Why then could there be 3 morphs of JUST males? When do you see 2 morphs of a species… male and female?Why then could there be 3 morphs of JUST males?
38 Game TheoryPredominating colored male species depends on availability to territory and number of matesHighly aggressive over large territoryMildly aggressive over a smaller space“sneaky” sex-stealerWhat type of selection is this?