Notice: Undefined index: inst in /var/www/vhosts/cbrp.co.uk/svpca.org/form/fm_Abst.php on line 299

Notice: Undefined index: inst in /var/www/vhosts/cbrp.co.uk/svpca.org/form/fm_Abst.php on line 299

Notice: Undefined index: inst in /var/www/vhosts/cbrp.co.uk/svpca.org/form/fm_Abst.php on line 299
SVPCA
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.
 
Mesozoic dinosaur diversity: taxic, phylogenetic and sampling approaches
 
SVPCA Conference
 
Platform presentation (20 minutes)
Authors
 
*Paul M Barrett
 
 
Alistair McGowan
 
 
Victoria Page
 
Abstract
 
Patterns of species-diversity provide important macroevolutionary information. Previous work on non-avian dinosaur diversity has been used to investigate the K/T extinction, effects of sea level on preservation, clade-clade competition and possible coevolutionary scenarios (e.g. Wang & Dodson, 2006). Most of these studies simply counted taxa to estimate standing diversity (taxic approach), while several incorporated information on ghost lineages (phylogenetic approach) or used rarefaction techniques (one potential sampling approach).

Studies on marine invertebrates have shown that the rock record (outcrop area, number of localities etc.) has a strong influence on diversity patterns (e.g. Smith, 2001), but similar corrections have not been applied to terrestrial clades. We compiled diversity curves for dinosaurs as a whole (including Mesozoic birds) and various component clades. Taxic diversity curves were obtained for species and genera: these were corrected using ghost lineages obtained from phylogenetic analyses. Statistical tests (Pearsonís and Spearmanís correlations) revealed strong positive relationships between the species/genus curves and the taxic/phylogenetic curves. This indicates that the same signals were being sampled in each case. A model of expected species-richness was then constructed for each clade using the number of dinosaur bearing formations (DBFs) present in each time interval as a proxy for outcrop area. Comparisons between the models and the diversity curves indicate that apparent patterns in ornithischian and theropod diversity can be explained largely as a result of changes in the number of DBFs. Conversely, sauropodomorph diversity bears little resemblance to that expected from the model, suggesting that at least some features of this curve result from genuine evolutionary signals.

London 2020