Functional and Character Disparity Are Decoupled in Turtle Mandibles.

Turtles have high shape variation of their mandibles, likely reflecting adaptations to a broad variety of food items and ingestion strategies. Here, we compare functional disparity measured by biomechanical proxies and character disparity measured by discrete morphological characters. Functional and character disparities vary between clades and ecological groups and are thus decoupled.

Abundance does not predict extinction risk in the fossil record of marine plankton.

A major premise of ecological neutral theory is that population size is inversely related to extinction risk. This idea is central to modern biodiversity conservation efforts, which often rely on abundance metrics to partially determine species extinction risk. However, limited empirical studies have tested whether extinction is indeed more probable for species with low abundances.

Late Neogene Lophophaenidae (Nassellaria, Radiolaria) from the eastern equatorial Pacific.

Lophophaenidae is a clade of polycystine radiolarians that was highly abundant and diverse in the Late NeogeneRecent eastern equatorial Pacific (EEP). Despite their importance in fossil plankton assemblages, lophophaenids have been neglected because of their generally small size, complex morphology, and weak taxonomic framework. These challenges have left many lophophaenid concepts poorly defined or lacking formal description.

Triton, a new species-level database of Cenozoic planktonic foraminiferal occurrences.

Planktonic foraminifera are a major constituent of ocean floor sediments, and thus have one of the most complete fossil records of any organism. Expeditions to sample these sediments have produced large amounts of spatiotemporal occurrence records throughout the Cenozoic, but no single source exists to house these data. We have therefore created a comprehensive dataset that integrates numerous sources for spatiotemporal records of planktonic foraminifera.

Marine plankton show threshold extinction response to Neogene climate change.

Ongoing climate change is predicted to trigger major shifts in the geographic distribution of marine plankton species. However, it remains unclear whether species will successfully track optimal habitats to new regions, or face extinction. Here we show that one significant zooplankton group, the radiolaria, underwent a severe decline in high latitude species richness presaged by ecologic reorganization during the late Neogene, a time of amplified polar cooling.