David F. Wright

Fossil crinoids are exceptionally suited to deep-time studies of community paleoecology and niche partitioning. By merging ecomorphological trait and phylogenetic data, this Element summarizes niche occupation and community paleoecology of crinoids from the Bromide fauna of Oklahoma (Sandbian, Upper Ordovician). Patterns of community structure and niche evolution are evaluated over a ~5 million-year period through comparison with the Brechin Lagerstätte (Katian, Upper Ordovician). The authors establish filtration fan density, food size selectivity, and body size as major axes defining niche differentiation, and niche occupation is strongly controlled by phylogeny. Ecological strategies were relatively static over the study interval at high taxonomic scales, but niche differentiation and specialization increased in most subclades. Changes in disparity and species richness indicate the transition between the early-middle Paleozoic Crinoid Evolutionary Faunas was already underway by the Katian due to ecological drivers and was not triggered by the Late Ordovician mass extinction.

Macroevolutionary inference has historically been treated as a two-step process, involving the inference of a tree, and then inference of a macroevolutionary model using that tree. Newer models blend the two steps. These methods make more complete use of fossils than the previous generation of Bayesian phylogenetic models. They also involve many more parameters than prior models, including parameters about which empiricists may have little intuition. In this Element, we set forth a framework for fitting complex, hierarchical models. The authors ultimately fit and use a joint tree and diversification model to estimate a dated phylogeny of the Cincta (Echinodermata), a morphologically distinct group of Cambrian echinoderms that lack the fivefold radial symmetry characteristic of extant members of the phylum. Although the phylogeny of cinctans remains poorly supported in places, this Element shows how models of character change and diversification contribute to understanding patterns of phylogenetic relatedness and testing macroevolutionary hypotheses.

Recent advances in statistical approaches called phylogenetic comparative methods (PCMs) have provided paleontologists with a powerful set of analytical tools for investigating evolutionary tempo and mode in fossil lineages. However, attempts to integrate PCMs with fossil data often present workers with practical challenges or unfamiliar literature. This Element presents guides to the theory behind and the application of PCMs with fossil taxa. Based on an empirical dataset of Paleozoic crinoids, example analyses are presented to illustrate common applications of PCMs to fossil data, including investigating patterns of correlated trait evolution and macroevolutionary models of morphological change. The authors emphasize the importance of accounting for sources of uncertainty and discuss how to evaluate model fit and adequacy. Finally, the authors discuss several promising methods for modeling heterogeneous evolutionary dynamics with fossil phylogenies. Integrating phylogeny-based approaches with the fossil record provides a rigorous, quantitative perspective on understanding key patterns in the history of life.

These important and incisive essays, spanning more than two decades of research and engagement, probe facets and episodes of infant baptism's fortunes over twenty centuries. The story of pedobaptism is traced from its shadowy beginnings as a variant of faith-baptism, through inflated Reformation defenses as infant-baptism monopolized baptismal thought and practice, to biblical and ecumenical reevaluations and hopeful contemporary rapprochements across divisive waters.

These important and incisive essays, spanning more than two decades of research and engagement, probe facets and episodes of infant baptism's fortunes over twenty centuries. The story of pedobaptism is traced from its shadowy beginnings as a variant of faith-baptism, through inflated Reformation defenses as infant-baptism monopolized baptismal thought and practice, to biblical and ecumenical reevaluations and hopeful contemporary rapprochements across divisive waters.

These important and incisive essays, spanning more than two decades of research and engagement, probe facets and episodes of infant baptisms fortunes over twenty centuries. The story of paedo baptism is traced from its shadowy beginnings as a variant of faithbaptism, through inflated Reformation defenses as it monopolized baptismal thought and practice, to biblical and ecumenical reevaluations and hopeful contemporary rapprochements across divisive waters.