Behavioral Biology Chapter 54

1. Behavioral BiologyChapter 54

2. Approaches • Behavior:the way an animal responds to stimulus in its environment • Proximate causation:“how” of behavior • Hormones • Impulse of nerve signal • Ultimate causation: “why” of behavior -influence on reproductive success or survival

3. Innate behavior: instinctive, no learning • Preset • Genetic Example: goose; Egg retrieval behavior is triggered by a sign stimulus. Innate releasing mechanism or fixed action pattern

4. Male stickleback fish will attack anything with a red underside • Does not need to be a fish What is sign stimulus? What is the fixed action pattern?

5. Behavioral Genetics Human twin study • identical genetically • 50 sets, twins raised separately • Similarity in personality, temperament, leisure time activities • Qenetics plays a role in determining behavior even in humans

6. Behavioral Genetics • fosB present: mother cares for her young • fosB absent: young are ignored and eventually die

7. Learning • Learning: altered behavior as a result of experiences • Nonassociative learning: no association is formed between two stimuli or between a stimulus and response • Habituation: • learn not to respond to repeated occurrences of stimulus

8. Learning • Associative learning: association between two stimuli or between a stimulus and a response • Conditioned behavior through association Associative learning is involved in predator-prey interactions: after being stung the toad learns not to eat bumblebees.

9. Classical conditioning: the paired presentation of two different kinds of stimuli with an association formed between them • Pavlovian conditioning • stimulus: meat • response: salivating • Conditioned stimulus: bell ringing • Conditioned response: After time, the dog salivates with only the ringing of the bell

10. Learning • Operant conditioning: animal learns to associate its behavior response with a reward or punishment • B.F. Skinner • Trial and error learning

11. Learning • Instinct and learning • Innate predispositions toward forming certain associations • Pigeons can learn to associate food with colors, but not with sound • Learning is possible only within the boundaries set by instinct • In nature, adaptation by learning is important to survival

12. Learning • Clark’s nutcracker can remember the locations of up to 2000 seed caches months after hiding them • Uses spatial memory

13. Development of Behavior • Parent-offspring interactions influence cognition and behavior • Imprinting: formation of social attachment to other individuals or develop preferences that will influence behavior later in life • Filial imprinting: attachment between parents and offspring • Konrad Lorenz

14. Development of Behavior • Goslings follow Konrad Lorenz as if he were their mother • 1973 Nobel Prize

15. Development of Behavior • Instinct and learning may interact as behavior develops • White-crowned sparrow males sing species-specific courtship song during mating • Genetic template: innate program to learn the appropriate song • Can not learn the song unless they hear it at a critical period in development

16. Development of Behavior • Exposed to own species song during development • Not exposed to song

17. Development of Behavior • Cuckoos are raised by a different species • Learn their own song: innate

18. Animal Cognition

19. Orientation and Migratory Behavior • Orientation: goal-oriented movements • Taxis: movement toward or away from a stimulus • Kineses: more or less active when stimulus intensity increases

20. Orientation and Migratory Behavior

21. Orientation and Migratory Behavior • Migrating animals must be capable of orientation and navigation • Navigation: the ability to set or adjust a bearing • Sun and stars • Earth’s magnetic field

22. Communication • Communication can play a key role in behaviors • Among members of thesame species • Between species Long-distance communication • Pheromones: chemical messengers • Acoustic signals • Light signals: firefly

23. Communication In group living • Guards: set off an alarm call • Social insects produce pheromones that trigger attack behavior • Ants deposit trail pheromones between nest and food source

24. Communication The waggle dance of honeybees

25. Communication Vocabulary to communicate identity of specific predators

26. Behavioral Ecology • Niko Tinbergen • BEHAVIORALECOLOGY: • Development • Physiological basis • Function: including evolutionary significance

27. Behavioral Ecology • Optimal foraging theory: natural selection favors individuals whose foraging behavior is energetically efficient

28. Behavioral Ecology Territorial behavior secures resources • Birds sing or display to signal their territory; energetically costly • Benefit: increased food intake

29. Sexual Selection Mate choice: Females evaluate a male’s quality • Females are usually responsible for gestation and lactation • higher investment • Eggs larger than sperm

30. Sexual Selection • Male seahorses brood and care for the young • Females compete for males when males are choosey

31. Sexual Selection • Sexual selection involves both: • Intrasexual selection: interactions between members of one sex • Intersexual selection: interactions between members of opposite sex (mate choice) • Sexual selection leads to the evolution of structures used in combat with other males. Ex. Antlers, horns

32. Sexual Selection • Intrasexual selection • Males • compete for opportunity to mate • defend their territory & females • mate with many females:

33. Altruism • Reciprocal altruism: Partnerships in which mutual exchanges of altruistic acts occur because they benefit both participants • Cheaters are discriminated against • Vampire bats • Share blood • meal • Altruism: the performance of an action that benefits another individual at a cost to the actor

34. Altruism • Kin selection: direct genetic advantage; selection favors relatives Kin selection in white-fronted bee-eater

35. Altruism Haplodiploidy and Hymenopteran social evolution • Bee hive: eusocial society • single queen lays eggsQueen shares 50% of alleles with offspring • Cooperative care of the • Brood

36. Social Systems • Advantages • Kin selection: greater odds of alleles surviving in the gene pool • Greater protection from predators • Increase feeding success