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Why giraffes have short necks … PowerPoint Presentation
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Why giraffes have short necks …

Why giraffes have short necks …

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Why giraffes have short necks …

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  1. Why giraffes have short necks … Michael P. Taylor University of Bristol dino@miketaylor.org.uk Mathew J. Wedel Western University of Health Sciences mathew.wedel@gmail.com

  2. Why giraffes have short necks … … and how sauropods got it right Michael P. Taylor University of Bristol dino@miketaylor.org.uk Mathew J. Wedel Western University of Health Sciences mathew.wedel@gmail.com

  3. 3-meter barrier for all non-aquatic animals

  4. Long-necked sauropod groups Upchurch et al. (2004:fig. 13.18)

  5. Long-necked sauropod groups Upchurch et al. (2004:fig. 13.18)

  6. Long-necked sauropod groups Upchurch et al. (2004:fig. 13.18) I suck ...

  7. Long-necked sauropod groups Upchurch et al. (2004:fig. 13.18) Magic I suck ...

  8. Factors contributing to long necks 1. No constraint on vertebral count Paraceratherium (Osborn 1923:fig 1)

  9. Factors contributing to long necks 1. No constraint on vertebral count Paraceratherium (Osborn 1923:fig 1) Mamenchisaurus (modified from Ouyang and Ye 2003:fig. 13)

  10. Factors contributing to long necks 2. Heads that did not process food

  11. Factors contributing to long necks 2. Heads that did not process food Diplodocus

  12. Factors contributing to long necks 2. Heads that did not process food Unholy Diplodocus ☓ Elephas hybrid

  13. Factors contributing to long necks 3. Absolutely large bodies

  14. Factors contributing to long necks 3. Absolutely large bodies

  15. Factors contributing to long necks 3. Absolutely large bodies C Crap.

  16. Factors contributing to long necks 3A. Large quadrupedal bodies C Crap.

  17. Factors contributing to long necks 3A. Large quadrupedal bodies C Crap.

  18. Factors contributing to long necks 3A. Large quadrupedal bodies C Crap.

  19. Factors contributing to long necks 3. Absolutely large bodies Parrish (2006) showed that sauropod neck length scales with torso length to the power 1.35

  20. Factors contributing to long necks 3. Absolutely large bodies Carpenter (2006) scaled Amphicoeliasfragillimus as 2.2 times Diplodocus. But Parrish suggests neck is 2.2^1.35 = 2.9 times => a neck 22 m long

  21. Factors contributing to long necks 4. Air-sacs overcame dead-space

  22. Factors contributing to long necks 4. Air-sacs overcame dead-space Like ostriches?

  23. Factors contributing to long necks 4. Air-sacs overcame dead-space But what about sperm whales? Paul 1998:fig. 11

  24. Factors contributing to long necks 4. Air-sacs overcame dead-space But what about sperm whales? Paul 1998:fig. 11

  25. Factors contributing to long necks 5. Vertebral architecture Diplodocus carnegii holotype CM 84, cervical 10 (Hatcher 1901:plate III)

  26. Factors contributing to long necks 5. Vertebral architecture Neural spine Prezygapophysis Post- zygapophysis Centrum Cervical rib Diplodocus carnegii holotype CM 84, cervical 10 (Hatcher 1901:plate III)

  27. Cervical vertebral innovations 1. Extreme pneumaticity 2. Bifid neural spines 3. Elongate cervical ribs

  28. Cervical vertebral innovations 1. Extreme pneumaticity Ostrich

  29. Cervical vertebral innovations 1. Extreme pneumaticity Diplodocus