Benthic foraminiferal Mn / Ca ratios reflect microhabitat preferences

Application of benthic foraminiferal Mg/Ca ratios to questions of Cenozoic climate change

We investigate the evolution of Cenozoic climate and ice volume as evidenced by the oxygen isotopic composition of seawater (NOsw) derived from benthic foraminiferal Mg/Ca ratios to constrain the temperature effect contained in foraminiferal N18O values. We have constructed two benthic foraminiferal Mg/Ca records from intermediate water depth sites (Ocean Drilling Program sites 757 and 689 from...

A culture-based calibration of benthic foraminiferal paleotemperature proxies: delta O-18 and Mg/Ca results

Benthic foraminifera were cultured for five months at four temperatures (4, 7, 14 and 21 C) to establish the temperature dependence of foraminiferal calcite δ18O and Mg/Ca. Two Bulimina species (B. aculeata and B. marginata) were most successful in terms of calcification, adding chambers at all four temperatures and reproducing at 7 and 14 C. Foraminiferal δ18O values displayed ontogenetic vari...

Cenozoic deep-Sea temperatures and global ice volumes from Mg/Ca in benthic foraminiferal calcite

A deep-sea temperature record for the past 50 million years has been produced from the magnesium/calcium ratio (Mg/Ca) in benthic foraminiferal calcite. The record is strikingly similar in form to the corresponding benthic oxygen isotope (delta(18)O) record and defines an overall cooling of about 12 degrees C in the deep oceans with four main cooling periods. Used in conjunction with the benthi...

Benthic Predators Influence Microhabitat Preferences and Settlement Success of Crown-of-Thorns Starfish (Acanthaster cf. solaris)

Like most coral reef organisms, crown-of-thorns starfish (Acanthaster spp.) are expected to be highly vulnerable to predation as they transition from a planktonic larval phase to settling among reef habitats. Accordingly, crown-of-thorns starfish might be expected to exhibit behavioural adaptations which moderate exposure to predation at this critical stage in their life history. Using pairwise...

Paleoceanographical proxies based on deep-sea benthic foraminiferal assemblage characteristics