Abstract
A morphometric analysis of third metapodials and first phalanges of Middle Awash and Hadar hipparions dating from the 6.0-3.0 Ma interval was conducted using two methods. Morphological comparisons using standard metrics were made using: 1) log10 ratio diagrams; 2) size independent variables developed with reference to scaling trends for hipparions in general. Results of these analyses suggest that hipparion diversity during this temporal interval was relatively low. A single dominant gracile lineage of Eurygnathohippus Van Hoepen, 1930, most plausibly derived from the Lothagam (Kenya) species Eurygnathohippus feibeli (Bernor & Harris, 2003), would appear to have persisted throughout this interval and is marked by increases in size with measured change in metapodial and phalangeal morphology. A rarer, more robust form is found in the Ethiopian sample at 4.0 Ma and is morphometrically similar to Eurygnathohippus turkanense Hooijer & Maglio, 1973 from late Miocene horizons of Lothagam. Another smaller form, of uncertain systematic status, appears likely late in the Kada Hadar sequence, c. 3.0 Ma.
Original language | English (US) |
---|---|
Pages (from-to) | 133-158 |
Number of pages | 26 |
Journal | Geodiversitas |
Volume | 27 |
Issue number | 1 |
State | Published - Mar 2005 |
Externally published | Yes |
Keywords
- Equidae
- Ethiopia
- Evolution
- Hadar
- Hipparionine
- Mammalia
- Middle Awash
- Morphometrics
- Postcranials
ASJC Scopus subject areas
- Geology
- Palaeontology