1 Chapter 49: Animal Behavior meerkats

2 Behavioral Ecology Behavior = everything an animal does & how it does it INNATE = inherited LEARNED = develop during animal’s lifetime Behavior & Natural Selection Behavior is part of phenotype acted upon by natural selection lead to greater fitness? greater reproductive success? greater survival?

3 Questions to ask . . . Proximate causes of behavior“how” & “what” Ultimate causes of behavior evolutionary significance “why” questions male songbird what triggers singing?  how does he sing?  why does he sing? Proximate cause questions Male 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 questions The 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

4 Ethology 1941 | 1973 pioneers in the study of animal behaviorKarl von Frisch Niko Tinbergen Konrad Lorenz

5 Complex Problem SolvingTypes of Behaviors Innate Fixed Action Pattern (FAP) Imprinting Associate Learning Habituation Observational Learning Insight Inherited Reflex Complex Problem Solving

6 Innate Behaviors Inherited (DNA)Automatic all individuals exhibit the behavior triggered by a stimulus

7 Example coordinated movements (walking, swimming, etc.) that occur in response to an external stimulus Taxis = change in direction automatic movement toward (+ taxis) or away from (- taxis) a stimulus phototaxis chemotaxis Kinesis = change in rate of movement in response to a stimulus The 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.

8 Migration Complex, but still innate“migratory restlessness” seen in birds bred & raised in captivity navigate by sun, stars, Earth magnetic fields Sandpiper Monarch migration Bird 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. Bobolink Golden plover ancient fly-ways

9 Fixed Action Pattern (FAP)male sticklebacks exhibit aggressive territoriality Fixed Action Pattern (FAP) innate sequence of unchangeable behaviors that are usually conducted to completion once started sign stimulus triggers FAP attack on red belly stimulus court on swollen belly stimulus

10 Digger wasp egg rolling in geese The “eyebrow-flash”Do 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 The “eyebrow-flash”

11 Imprinting Both innate & learning componentsLearning at a specific critical time But 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 explanations Konrad Lorenz

12 During critical period, the animal acquires memory of certain salient stimuli in its "home" environment (taste of the host plant, smell of the nest site, etc.)

13 Associative Learning learning to associate one feature of the environment (stimulus) with another operant conditioning trial & error learning associate behavior with reward or punishment classical conditioning Pavlov’s Dogs associate a “neutral stimulus” with a “significant stimulus”

14 Operant conditioning Skinner box “trial & error”mouse learns to associate behavior (pressing lever) with reward (food pellet)

15 Classical conditioningIvan Pavlov’s dogs connect reflex behavior (salivating at sight of food) to associated stimulus (ringing bell)

16 Habituation Loss of response to stimulus “cry-wolf” effectlearn not to respond to repeated occurrences of stimulus

17 Observational Learningwatch & learn memory of patterns or events when there is no apparent reward or punishment

18 Insight requires intelligence and social behaviors problem-solvingtool use crow

19 Types of Social Behaviorslanguage agonistic behaviors dominance hierarchy altruistic behavior territoriality mating behavior

20 Language Honey bee “waggle dance” communicationdance shows location of food source

21 Agonistic Behaviors threatening & submissive ritualssymbolic, usually no harm done

22 Dominance hierarchy social ranking within a group

23 Altruistic behavior reduces individual fitness but increases fitness of recipient Paradox: self-sacrificial men “would, on average, perish in larger number than other men” KIN SELECTION  meerkats Old view: survival of the fittest organism New view survival of the fittest GENE (family genes)

24 Territoriality Define: methods by which an individual (or group) protects its territory from others of its species Mark boundaries, chase, fight Increases during breeding season Cost: might get hurt (survival risk) Benefits: uninterrupted mating, raise young in area with less competition (reproductive benefit)

25 Mating & Parental behaviorGenetic influences  behavior changes at different stages of mating Environmental influences can modify behavior depends on: quality of diet social interactions

26 Social interaction requires communicationPheromones chemical signal that stimulates a response from other individuals alarm pheromones sex pheromones

27 Pheromones Female mosquito use CO2 concentrations to locate victimsmarking territory Spider using moth sex pheromones, as allomones, to lure its prey The female lion lures male by spreading sex pheromones, but also by posture & movements The 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.