1 / 75

Chapter 49: Behavioral Ecology

Chapter 49: Behavioral Ecology. Animal Behavior. Observable coordinated responses to stimuli Originates with genes that direct the formation of tissues and organs of the animal body. Nervous System. Detects processes and integrates information about stimuli

Download Presentation

Chapter 49: Behavioral Ecology

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Chapter 49: Behavioral Ecology

  2. Animal Behavior • Observable coordinated responses to stimuli • Originates with genes that direct the formation of tissues and organs of the animal body

  3. Nervous System • Detects processes and integrates information about stimuli • Commands muscles and glands to make suitable responses

  4. Genes and Behavior • Some variations in behavior have a genetic basis • Arnold showed that garter snakes’ taste for slugs has genetic basis • Hybrid snakes showed behavior intermediate between parental types

  5. Fig. 49-2a, p.900

  6. Fig. 49-2b, p.900

  7. Hormones and Bird Song • Sex hormones produced during development prime male birds to sing • As adults, males will sing only when days are long and levels of the hormone melatonin are low

  8. Fig. 49-3a, p.900

  9. Instinctive Behavior • Performed without having been learned • Usually triggered by simple sign stimuli • Response is a stereotyped motor program, a fixed-action pattern

  10. Fig. 49-4a, p.901

  11. Fig. 49-4b, p.901

  12. Fig. 49-5, p.901

  13. Learned Behavior • Responses change with experience • Some categories of learned behavior Imprinting Spatial learning Insight learning Habituation Classical conditioning Operant conditioning

  14. Imprinting • Time-dependent learning • Triggered by exposure to a sign stimulus during a sensitive period • Young geese imprint on a moving object and treat it as “mother”

  15. Fig. 49-7b, p.902

  16. Classical Conditioning • First demonstrated by Pavlov • An autonomic response becomes associated with a novel stimulus • Salivation became associated with sound of bell that accompanied feeding

  17. Operant Conditioning • A voluntary action becomes associated with its consequences • A toad may attempt to eat a wasp with a black and gold pattern and be stung • Thereafter, the toad will be conditioned to avoid eating similar insects

  18. Habituation • An individual learns not to respond to a stimulus that has neither good nor bad consequences. Deals with stimuli in their own habitat • Pigeons in cities learn that people are no threat and do not flee from them

  19. Spatial Learning • Through experience with an environment, an organism creates a mental map • Squirrels and where they store food • Where water locations are for organisms

  20. Insight Learning • An animal solves a problem without trial-and-error attempts at a solution • Captive chimpanzees show insight learning when they solve a novel problem, as when they stack boxes to reach food that is out of reach

  21. Bird Song: Instinct + Learning • Bird comes prewired to listen to certain acoustical cues; instinctively pays attention to particular sounds • Which dialect the bird sings depends on what song it hears; it learns the details of the song from others around it

  22. Fig. 49-7a, p.902

  23. Adaptive Behavior • Behavior that promotes propagation of an individual’s genes • Its frequency will be maintained or increase in successive generations

  24. Selection for Behavior • Some variation in behavior has a genetic basis • Some behavior promotes reproductive success (is adaptive) • Genes that encode adaptive behavior will increase in population

  25. Selfish and Altruistic Behavior • Selfish behavior promotes own survival • Altruistic behavior helps others at the expense of the altruist; may be adaptive under certain circumstances

  26. Selfish Ravens • Some ravens that find carcasses call and alert others • Are their calls altruistic? No • Callers are birds without territories • Calling brings in others to help caller get food in a pair’s territory

  27. Starling Nest Decoration • Starlings line nest with wild carrot • Experiments have shown this behavior minimizes mites Figure 49-8 Page 903 Experimental nests Control nests

  28. Fig. 49-8a, p.903

  29. Fig. 49-8b, p.903

  30. Communication Signals • Intraspecific signals will evolve only if they benefit both signaler and receiver • Variety of signal modalities Pheromones Tactile signals Visual signals Acoustical signals

  31. Pheromones • Chemical signals that diffuse through air or water • May bring about behavioral change in receiver or cause physiological change (priming pheromones)

  32. Acoustical Signals • Sounds used in communication • Used to attract mates, secure territory, warn off rivals • May also be used to communicate danger, keep groups together

  33. Visual Displays • Important in courtship and in aggression • Baring of teeth by baboon communicates threat • Play bow in wolves solicits play behavior • Flashing of fireflies attracts mates

  34. Fig. 49-9a, p.904

  35. Fig. 49-9b, p.904

  36. Fig. 49-9c, p.904

  37. Tactile Display • Signaler and receiver communicate by touch • Honeybee dance language Food close Food distant Figure 49-10  Page 905

  38. Fig. 49-10a1, p.905

  39. When bee moves straight down comb, recruits fly to source directly away from the sun. When bee moves to right of vertical, recruits fly at 90˚ angle to right of the sun. When bee moves straight up comb, recruits fly straight toward the sun. Fig. 49-10a-c, p.905

  40. Signal Variation • Some signals never vary • Others can be varied to convey information about the signaler • Composite signals combine information encoded in more than one cue; more potential for variation and information

  41. Ritualized Displays • Body parts may be enhanced or colored in way that enhances the display • Ritualization is often important in courtship displays

  42. Illegitimate Signals • An illegitimate receiver intercepts a signal meant for individuals of another species • Termite smells pheromone of invading ant and attacks it • An illegitimate signaler mimics signals • Predatory fireflies mimic females of prey species

  43. Sexual Selection • Reproductive success is measured in number of offspring produced • Reproductive success can be enhanced by increasing the number of matings or the quality of mates

  44. Fig. 49-11b, p.906

  45. Fig. 49-11c, p.906

  46. Male Reproductive Strategy • Produce energetically inexpensive sperm • Often provide no parental care • Often maximize reproductive success by mating with as many females as possible

  47. Fig. 49-11d, p.906

  48. Female Reproductive Strategy • Produce large, energetically expensive eggs • Often provide parental care • Often increase reproductive success by increasing the quality of their mates

  49. Choosy Females • Female choice can dictate rules of male competition and shape male behavior • Selects for males that appeal to females • Male sage grouse display in leks • Male penguins presenting “gifts”-pebbles

  50. Male Contests • Females of some species cluster in groups • Males of such species may fight one another for access to harems • Selects for large males that can defeat other males in contests

More Related