Notice: Undefined index: inst in /var/www/vhosts/ on line 299
Please check the details of your abstract, then click the 'Submit Abstract' button if you are satisfied.
If you want to edit the content, click on the 'Edit Submission' button.
Dawn horses and the North American connection
SVPCA Conference
Platform presentation (20 minutes)
*Jerry J Hooker
There is a particularly dense stratigraphic record of primitive equoids (dawn horses) in the North American Early Eocene (Gingerich, 1991). The same does not hold true for Europe, where remains are usually either rare or fragmentary (Hooker, 1994). Europe is also where the endemic equoid family Palaeotheriidae evolved. The shortcoming of the European record has been partially rectified by long-term collecting at one Early Eocene site, that of Abbey Wood, UK. Here, a substantial assemblage belonging to the genus Pliolophus has been accumulated. In addition, the first upper dentition since the 19th century of the type species of Hyracotherium, H. leporinum Owen, 1841, has recently been found in the London Clay near the type locality of Studd Hill, Herne Bay, Kent. These new finds begin to address the tangled taxonomic and palaeobiogeographic problems that surround North American and European dawn horses, which are largely due to extensive intraspecific variation. Coding the variable characters for cladistic analysis is not straightforward, particularly when including small as well as large assemblages. Nevertheless, the weight of evidence favours independent evolution in the two continents, following a single phase of dispersal from Europe to North America at the beginning of the Eocene.
London 2020