Friends or Foes: Facing the Facts About American Crows

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David Craig, PhD, Associate Professor and Chair of Biology at Willamette University, discusses his research on crow behavior, in particular crows' ability to recognize faces.

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  • http://www.npr.org/templates/story/story.php?f=1001&ft=1&storyId=106826971
  • Friends or Foes: Facing the Facts About American Crows

    1. 1. Friends or Foes: Facing the Facts About American Crows David P. Craig Willamette University - Department of Biology
    2. 2. Who knows what this is ?
    3. 3. The Rook (Corvus frugilegus) i.e. the food-gathering crow of Eurasia
    4. 4. Everybody has a crow story
    5. 5. Everybody has a crow story
    6. 6. Everybody has a crow story
    7. 7. Everybody has a crow story
    8. 8. ‘Welcome to Science Whitewing” “I got him, John!” “How was your climb?”
    9. 9. Predator Recognition by Crows
    10. 10. Crow Call TypesCaw Scold
    11. 11. Sociality and Relatively Large Brains May Enable Discrimination
    12. 12. Can You Tell the Difference Between Dick Cheney and a Caveman? CheneyCaveman
    13. 13. CheneyCaveman Can Crows Tell the Difference Between Dick Cheney and a Caveman?
    14. 14. Two Main Questions 1) Can wild American Crows learn to recognize individual people? 2) Does social learning take place?
    15. 15. What About Ordinary Faces?
    16. 16. Study Treatments • Ten trials per site • Nine treatments per trial – Negative mask – Five neutral masks – Negative mask + armband – Two neutral masks + armband
    17. 17. The dangerous face is always recognized, and especially likely to attract a mob, but not perfectly.
    18. 18. Two Mask Trials • One mask at a time • Choice among masks
    19. 19. When forced to select the Dangerous from a Neutral Mask, when both were presented simultaneously, Crows accurately discriminated among all the ordinary masks.
    20. 20. Two Main Questions 1) Can American Crows learn to recognize individual people? 2) Does social learning take place?
    21. 21. Acquisition of Information • Individual “trial and error” Learning – Allows Flexibility, – But Dangerous • Social Learning – Flexible – Reduced Cost
    22. 22. Three Opportunities for Observational Learning 1) At time of capture 2) Associating with crows who were captured when they encounter the trapping mask at a later date 3) Young of crows who had been captured
    23. 23. Spread in the Geographical Extent of Scolding the Extraordinary Face over 2.8 Years
    24. 24. Urban Site (B.) shows a result similar to the pilot study but not elsewhere (A.) Downtown urban site has similar density and unpredictable identity of humans as does the pilot campus site Dangerous mask downtown was bald man, most similar to extraordinary face from campus
    25. 25. Individuals with the Direct Experience of Being Captured Learned to Discriminate Faces More Accurately Than Those Only Observing Capture or Subsequent Scolding of Captors
    26. 26. Vertical Learning • We put a radio tag on young crows (without ourselves wearing a mask) whose parents scold the dangerous mask • While under parental care, the young observe their parents scold the dangerous mask • Independent of parental care, the young crow scolds the dangerous mask
    27. 27. Crow Paradox
    28. 28. Face Recognition
    29. 29. Halloween Mask Sales on Amazon Predicted Election
    30. 30. San OnOfre aka St OnuphriuS by the SpaniSh painter, franciScO cOllanteS (1599-1656) MuSeO del pradO
    31. 31. CULT of CORAX

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