Animals within social groups respond to costs and benefits of sociality by adjusting the proportion of time they spend in close proximity to other individuals in the group (cohesion). Variation in cohesion between individuals, in turn, shapes important group‐level processes such as subgroup formation and fission–fusion dynamics. Although critical to animal sociality, a comprehensive understanding of the factors influencing coh...

We investigated the controls on the δ 15 N values of shell‐bound organic matter of planktonic foraminifera (foraminifera‐bound δ 15 N, or FB‐ δ 15 N). The bulk biomass δ 15 N of live foraminifera collected from plankton tows at Sta. S in the Sargasso Sea is within ∼1‰ of the FB‐ δ 15 N of the same species picked from surface sediments from the low‐latitude North Atlantic. The FB‐ δ 15 N value in the surface sediments is strong...