Fossil vertebrates commonly are preserved in paleosols that originally formed on the floodplains of ancient rivers. Laterally adjacent paleosols that differ in terms of their chemistry and morphology due to geological and environmental gradients on the ancient floodplain are called pedofacies. Vertebrate fossil assemblages from the Willwood Formation (Bighorn Basin, Wyoming) are investigated to determine if there is a relationship between faunal composition and pedofacies. This question is particularly important for the Willwood Formation because it records dramatic temporal changes in both faunal composition and pedofacies across the Paleocene–Eocene boundary—an interval marked by pronounced global warming. To understand the underlying causes of these temporal patterns, it is important to know the degree to which pedofacies and faunal composition are linked. Two separate analyses are conducted to investigate the relationship between pedofacies and faunal composition. Analysis 1 evaluates faunal compositions of established localities that are stratigraphically adjacent but characterized by different mean pedofacies. Results indicate that faunal compositions of these localities are not related to pedofacies but instead correspond to differences in the estimated body masses of the taxa. Results of Analysis 2, which evaluates new paleosol-specific collections from the same stratigraphic interval, indicate that different pedofacies are characterized by nearly identical faunas. The only exception is lizards, which are significantly more abundant in mature paleosols. Environmental gradients on the ancient floodplain seem to have exerted very little control on faunal composition at this spatial scale, but size sorting may have been an important taphonomic process in these Willwood collections.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.
Vol. 20 • No. 4