A new approach to determining the habitual neck
A new approach to determining the habitual neck posture of sauropods based on the behaviour of extant animals Michael P. Taylor 1 Mathew J. Wedel 2 Darren Naish 1 1 Palaeobiology Research Group, School of Earth and Environmental Sciences, University of Portsmouth, Burnaby Building, Burnaby Road, Portsmouth PO 1 3 QL, UK 2 Department of Anatomy and College of Podiatric Medicine, Western University of Health Sciences, 309 E. Second Street, Pomona, California 91766 -1854, USA.
Historical background The earliest sauropod reconstructions had horizontal necks Camarasaurus (Ryder 1877) Reprinted by Osborn and Mook (1921: plate LXXXII)
Historical background The earliest sauropod reconstructions had horizontal necks Brontosaurus (Marsh 1883: plate I)
Historical background The earliest sauropod reconstructions had horizontal necks Diplodocus carnegii (Hatcher 1901: plate VIII)
Historical background Later sauropod reconstructions had raised necks Camarasaurus (Osborn and Mook 1921: plate LXXXIV)
Historical background Later sauropod reconstructions had raised necks Brachiosaurus brancai (Janensch 1950 b: plate VIII)
Historical background Later sauropod reconstructions had raised necks Brachiosaurus brancai (Paul 1988: fig. 1)
Historical background Later sauropod reconstructions had raised necks ? ! Brachiosaurus brancai (Paul 1988: fig. 1)
Historical background Later sauropod reconstructions had raised necks Brontosaurus (Zallinger's 1947 mural at YPM)
Recent work has reverted to horizontal Necks considered low and inflexible Leicester City Museum Cetiosaurus oxoniensis
Recent work Necks considered low and inflexible Martin (1987: fig. 2)
Recent work Osteological neutral pose (ONP) Stevens and Parrish (2005 b: fig. 10. 3 A) – same specimen
Recent work Osteological neutral pose (ONP) Stevens and Parrish (2005 a: fig. 6. 5 B) – Diplodocus carnegii
Recent work (Giraffes are different: ONP gives rise to an erect neck) Stevens and Parrish (2005 a: fig. 6. 2) – Giraffe
Recent work Sauropod necks considered low and inflexible Stevens and Parrish (2005 a: fig. 6. 14) – Diplodocus carnegii
Recent work Necks considered low and inflexible Stevens and Parrish (1999: fig. 2 B) – Diplodocus carnegii Dino. Morph
Recent work Necks considered low and inflexible Stevens and Parrish (1999: 798, 800)
Recent work Necks considered low and inflexible Stevens and Parrish (1999: 798, 800)
Recent work Necks considered low and inflexible Stevens and Parrish (1999: 798, 800)
Recent work Necks considered low and inflexible Claim: ONP is sub-horizontal in all sauropods
Recent work Necks considered low and inflexible Claim: ONP is sub-horizontal in all sauropods Claim: ONP is the habitual posture
Recent work Neck held high Christian and Dzemski (2007) – stress patterns
Recent work Neck held high Similar findings by. . . Christian and Dzemski (2007) – stress patterns
Recent work Neck held high Similar findings by. . . Christian and Heinrich (1998) Christian and Dzemski (2007) – stress patterns
Recent work Neck held high Similar findings by. . . Christian and Heinrich (1998) Christian (2002 a) Christian and Dzemski (2007) – stress patterns
Recent work Neck held high Similar findings by. . . Christian and Heinrich (1998) Christian (2002 a) Christian (2002 b) Christian and Dzemski (2007) – stress patterns
Recent work Neck held high Similar findings by. . . Christian and Heinrich (1998) Christian (2002 a) Christian (2002 b) Christian (2004) Christian and Dzemski (2007) – stress patterns
Recent work Neck held high n a m e n O ? e d a s u r c Similar findings by. . . Christian and Heinrich (1998) Christian (2002 a) Christian (2002 b) Christian (2004) Christian and Dzemski (2007) – stress patterns
The state of the art Low necks popularised by the BBC (and AMNH)
The state of the art Low necks popularised by the BBC (and AMNH) n o d e s a b l l A P N O
But
But What do extant animals do?
Habitual posture of extant animals Vidal et al (1986) on “unrestrained awake animals” Cat, sitting and standing (Vidal et al. 1986: fig. 3)
Habitual posture of extant animals Vidal et al (1986) on “unrestrained awake animals” But what about nice, cuddly bunny-rabbits?
Habitual posture of extant animals Nice, cuddly bunny-rabbits have vertical necks, too. Rabbit in semi-alert posture (Vidal et al. 1986: fig. 4)
Habitual posture of extant animals And so do rats and guinea pigs Rat and guinea pig (Vidal et al. 1986: fig. 5 B-C)
Habitual posture of extant animals And so do rats and guinea pigs ? s l a m m a m t s u j t i Is Rat and guinea pig (Vidal et al. 1986: fig. 5 B-C)
Habitual posture of extant animals What about the humble chicken?
Habitual posture of extant animals Chicken necks habitually bend backwards! (Vidal et al. 1986: fig. 7)
Vidal et al. 's (1986) key findings Habitual posture is not ONP
Vidal et al. 's (1986) key findings Habitual posture is not ONP Cervicodorsal joint is maximally extended
Vidal et al. 's (1986) key findings Habitual posture is not ONP Cervicodorsal joint is maximally extended Craniocervical joint is maximally flexed
Vidal et al. 's (1986) key findings Habitual posture is not ONP Cervicodorsal joint is maximally extended Craniocervical joint is maximally flexed Median part of neck is mostly held rigid
Vidal et al. 's (1986) key findings Habitual posture is not ONP Cervicodorsal joint is maximally extended Craniocervical joint is maximally flexed Median part of neck is mostly held rigid The neck is raised and lowered at end joints
Cold-blooded/sprawling amniotes Alligator (Claessens, unpublished photo)
Cold-blooded/sprawling amniotes Unspecified lizard (Vidal et al. 1986: fig. 8 A) Varanid lizard (Brainerd and Owekowicz 2006: fig. 4)
Cold-blooded/sprawling amniotes Turtle (Landberg et al. 2003: fig. 8)
Non-amniote tetrapods Salamander (Simons et al. 2000: fig. 4)
Neck posture mapped onto cladogram
Neck posture mapped onto cladogram
Neck posture mapped onto cladogram Upright posture
Neck posture mapped onto cladogram Upright posture Homeothermy
Diplodocus carnegii (based on Hatcher 1901) (Skull orientation based on occipital condyle)
Dicraeosaurus deathmatch! Janensch (1936: plate 16) vs. Wilson (2002: fig. 1)
Dicraeosaurus deathmatch! Janensch (1936: plate 16) vs. Wilson (2002: fig. 1)
Also. . . what does “neutral” actually mean? Modified from Stevens and Parrish (2005 b: fig. 6. 8) Neutral pose
Also. . . what does “neutral” actually mean? Modified from Stevens and Parrish (2005 b: fig. 6. 8) Ventrally deflected by 8°
Also. . . what does “neutral” actually mean? Modified from Stevens and Parrish (2005 b: fig. 6. 8) Dorsally deflected by 8°
Thanks for listening Your neck (all seven vertebrae) Sauroposeidon C 8 (one vertebra) Visit our blog: Sauropod Vertebra Picture of the Week http: //svpow. wordpress. com/
- Slides: 59