One way to build larger, more comprehensive phylogenies is to combine the vast amount of
phylogenetic information already available. We review the two main strategies for …

EXECUTIVE SUMMARY A Biological Review Team (BRT) convened by the National Marine
Fisheries Service assessed the best available information concerning the status of ringed …

The distribution, physical development, pelage, dentition, feeding behavior, reproduction,
causes of mortality, and population structure of the Pacific walrus (Odobenus rosmarus …

Avian paleontology has long been a poor stepsister to its mammalian counterpart, a fact that
may be attributed in some measure to an insufRciency of qualified workers and to the …

When the Bering Strait between Alaska and Siberia opened about 3.5 Ma during the early
Pliocene, cool-temperate and polar marine species were able to move between the North …

Lactation represents a major proportion of maternal reproductive effort. In ungulates the
energetic costs of lactation comprise 75–80% of the total energetic costs of reproduction …

ABSTRACT A 30‐year renaissance in research on fossil marine mammals has brought
advances on several fronts and suggests potential directions for future study. Gingerich and …

The freshwater ecosystem may be as old as most life. Although freshwater life is
taxonomically impoverished in comparison with marine and terrestrial biotas and ultimately …

Background Phylogenetic comparative methods are often improved by complete
phylogenies with meaningful branch lengths (eg, divergence dates). This study presents a …

Previous hypotheses for the origin and diversification of pinnipeds have followed a narrative
approach based mostly on dispersalist (ie, center of origin) explanations. Using an analytical …