This paper focuses on inter-individual variability and temperature sensitivity of Mg incorporation in calcite shells of the benthic foraminifer Bulimina marginata. The manuscript is well-written; in particular, the Discussion section is well-thought-through. The topics attract many readers interested in biocalcification and paleo-temperature reconstructions. However, I consider this paper needs...

relates stream length (L, mi) to drainage-basin area (A, mi). In CG-6 (“Solving Problems,” May 1999), Stokes' Law was used to find the travel time for a dead foraminifer to settle to the abyssal plain. This equation, which relates settling velocity (v) of a small, spherical particle to the densities of the settling particle and fluid (ρs and ρf, respectively), the viscosity of the fluid (μ), an...

We made shell size measurements of the planktic foraminifer Neogloboquadrina pachyderma (sinistral) using samples from IODP Site U1304, the North Atlantic. We found that mean and maximum shell sizes began to increase around 1.1 Ma, and that several episodic changes in test size occurred during 0.6 – 0.35 Ma. Test size reached a maximum during the late Quaternary. Based on correlation with previ...

In this study, we show that the rate of shell precipitation in the extant planktic foraminifer Orbulina universa is sufficiently rapid that 12 h calcification periods in O-labeled seawater can be resolved and accurately measured using secondary ion mass spectrometry (SIMS) for in situ dO analyses. Calcifying O. universa held at constant temperature (22 C) were transferred every 12 h between amb...

[1] Proxy records from two piston cores in the Gulf of Mexico (GOM) provide a detailed (50–100 year resolution) record of climate variability over the last 14,000 years. Long-term (millennial-scale) trends and changes are related to the transition from glacial to interglacial conditions and movement of the average position of the Intertropical Convergence Zone (ITCZ) related to orbital forcing....

This article presents data derived by the USGS Pliocene Research, Interpretation and Synoptic Mapping (PRISM) Project. PRISM has generated planktic foraminifer census data from core sites and outcrops around the globe since 1988. These data form the basis of a number of paleoceanographic reconstructions focused on the mid-Piacenzian Warm Period (3.264 to 3.025 million years ago). Data are prese...

Genes encoding elongation factor-like (EFL) proteins, which show high similarity to elongation factor-1alpha (EF-1alpha), have been found in phylogenetically distantly related eukaryotes. The sporadic distribution of "EFL-containing" lineages within "EF-1alpha-containing" lineages indirectly, but strongly, suggests lateral gene transfer as the principal driving force in EFL evolution. However, ...

[1] Benthic foraminiferal Cd/Ca is an important proxy for seawater paleonutrient concentrations and therefore deep ocean paleocirculation. Although previous work suggests that the incorporation of Cd into benthic foraminiferal calcite is insensitive to temperature, at least one species of planktonic foraminifer appears to be strongly influenced. The present study provides a closer look at the r...