Fossil evidence and stages of elongation of the Giraffa camelopardalis neck
Several evolutionary theories have been proposed to explain the adaptation of the long giraffe neck; however, few studies examine the fossil cervical vertebrae. We incorporate extinct giraffids, and the okapi and giraffe cervical vertebral specimens in a comprehensive analysis of the anatomy and elo...
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
The Royal Society
2015-01-01
|
| Series: | Royal Society Open Science |
| Subjects: | |
| Online Access: | https://royalsocietypublishing.org/doi/pdf/10.1098/rsos.150393 |
| _version_ | 1818341152520142848 |
|---|---|
| author | Melinda Danowitz Aleksandr Vasilyev Victoria Kortlandt Nikos Solounias |
| author_facet | Melinda Danowitz Aleksandr Vasilyev Victoria Kortlandt Nikos Solounias |
| author_sort | Melinda Danowitz |
| collection | DOAJ |
| description | Several evolutionary theories have been proposed to explain the adaptation of the long giraffe neck; however, few studies examine the fossil cervical vertebrae. We incorporate extinct giraffids, and the okapi and giraffe cervical vertebral specimens in a comprehensive analysis of the anatomy and elongation of the neck. We establish and evaluate 20 character states that relate to general, cranial and caudal vertebral lengthening, and calculate a length-to-width ratio to measure the relative slenderness of the vertebrae. Our sample includes cervical vertebrae (n=71) of 11 taxa representing all seven subfamilies. We also perform a computational comparison of the C3 of Samotherium and Giraffa camelopardalis, which demonstrates that cervical elongation occurs disproportionately along the cranial–caudal vertebral axis. Using the morphological characters and calculated ratios, we propose stages in cervical lengthening, which are supported by the mathematical transformations using fossil and extant specimens. We find that cervical elongation is anisometric and unexpectedly precedes Giraffidae. Within the family, cranial vertebral elongation is the first lengthening stage observed followed by caudal vertebral elongation, which accounts for the extremely long neck of the giraffe. |
| first_indexed | 2024-12-13T15:54:15Z |
| format | Article |
| id | doaj.art-dad6a18520534907820a6a2c0065fdf3 |
| institution | Directory Open Access Journal |
| issn | 2054-5703 |
| language | English |
| last_indexed | 2024-12-13T15:54:15Z |
| publishDate | 2015-01-01 |
| publisher | The Royal Society |
| record_format | Article |
| series | Royal Society Open Science |
| spelling | doaj.art-dad6a18520534907820a6a2c0065fdf32022-12-21T23:39:22ZengThe Royal SocietyRoyal Society Open Science2054-57032015-01-0121010.1098/rsos.150393150393Fossil evidence and stages of elongation of the Giraffa camelopardalis neckMelinda DanowitzAleksandr VasilyevVictoria KortlandtNikos SolouniasSeveral evolutionary theories have been proposed to explain the adaptation of the long giraffe neck; however, few studies examine the fossil cervical vertebrae. We incorporate extinct giraffids, and the okapi and giraffe cervical vertebral specimens in a comprehensive analysis of the anatomy and elongation of the neck. We establish and evaluate 20 character states that relate to general, cranial and caudal vertebral lengthening, and calculate a length-to-width ratio to measure the relative slenderness of the vertebrae. Our sample includes cervical vertebrae (n=71) of 11 taxa representing all seven subfamilies. We also perform a computational comparison of the C3 of Samotherium and Giraffa camelopardalis, which demonstrates that cervical elongation occurs disproportionately along the cranial–caudal vertebral axis. Using the morphological characters and calculated ratios, we propose stages in cervical lengthening, which are supported by the mathematical transformations using fossil and extant specimens. We find that cervical elongation is anisometric and unexpectedly precedes Giraffidae. Within the family, cranial vertebral elongation is the first lengthening stage observed followed by caudal vertebral elongation, which accounts for the extremely long neck of the giraffe.https://royalsocietypublishing.org/doi/pdf/10.1098/rsos.150393neckelongationgiraffidaesamotheriumcervical vertebrae |
| spellingShingle | Melinda Danowitz Aleksandr Vasilyev Victoria Kortlandt Nikos Solounias Fossil evidence and stages of elongation of the Giraffa camelopardalis neck Royal Society Open Science neck elongation giraffidae samotherium cervical vertebrae |
| title | Fossil evidence and stages of elongation of the Giraffa camelopardalis neck |
| title_full | Fossil evidence and stages of elongation of the Giraffa camelopardalis neck |
| title_fullStr | Fossil evidence and stages of elongation of the Giraffa camelopardalis neck |
| title_full_unstemmed | Fossil evidence and stages of elongation of the Giraffa camelopardalis neck |
| title_short | Fossil evidence and stages of elongation of the Giraffa camelopardalis neck |
| title_sort | fossil evidence and stages of elongation of the giraffa camelopardalis neck |
| topic | neck elongation giraffidae samotherium cervical vertebrae |
| url | https://royalsocietypublishing.org/doi/pdf/10.1098/rsos.150393 |
| work_keys_str_mv | AT melindadanowitz fossilevidenceandstagesofelongationofthegiraffacamelopardalisneck AT aleksandrvasilyev fossilevidenceandstagesofelongationofthegiraffacamelopardalisneck AT victoriakortlandt fossilevidenceandstagesofelongationofthegiraffacamelopardalisneck AT nikossolounias fossilevidenceandstagesofelongationofthegiraffacamelopardalisneck |