I investigate the impact of changes in environment and climate on living organisms on various time scales, from millions of years to decades, with the common focal point of benthic foraminifera (eukaryotic unicellular organisms). Foraminifera live in salt or at least brackish water, so I concentrate on the oceans, from the deep sea up into tidal salt marshes. The deep sea is the largest habitat on Earth, supports a high diversity of organisms, but is one of the least known. I am interested in understanding the development of high-diversity deep-sea faunas through periods of major climate change and mass extinction, such as the mass extinction caused by meteorite impact at the end of the Cretaceous (65 million years ago), which did not affect benthic foraminifera significantly. I participated in Ocean Drilling Program Leg 208 in the South East Atlantic Ocean, studying causes and consequences of extreme warm climates on Earth, including the extinction of deep-sea benthic foraminifera at the end of the Paleocene (55 million years ago), linked to an early greenhouse episode. I also look at changes in deep-sea faunas during other periods of global change, such as the earliest Oligocene (~33.5 million years ago) when the Antarctic ice sheet originated, and am interested in possible links between glaciation and initiation of the AntArctic Circumpolar Current. I look into the climate swings of ice ages during the last few hundred thousands of years. Together with Joop Varekamp I work at the edge of the oceans in coastal salt marshes in Connecticut and New Jersey, trying to understand the ecology of salt marshes as well as rates of relative sea-level rise during the last 2000 years. We also cooperate in research on the changing environments and ecosystems in Long Island Sound, at time scales varying from the last 15,000 years to the time since European settlement and industrial revolution, and the eutrophication caused by human presence.
Cretaceous-Tertiary Boundary
Surviving mass extinction by bridging the benthic/planktic divide (with Kate F. Darling, Simone A. Kasemann, Heidi A. Seears, Christopher W. Smart, and Christopher M. Wade), Proc. Natl. Acad. Sci. USA (2009)
Evolution of planktic organisms from benthic ancestors is commonly thought to represent unidirectional expansion into...
Cenozoic Mass Extinctions in the Deep Sea; What Disturbs the Largest Habitat on Earth?, Geological Society of America Special Paper (2007)
Deep-sea benthic foraminifera live in the largest habitat on Earth, constitute an important part of...
Deep Sea Environments Across the Cretaceous/Paleogene boundary in the eastern South Atlantic Ocean, Marine Micropaleontology (2007)
Cretaceous/Paleogene Boundary Bathyal Paleo-Environments in the Central North Pacific (DSDP Site 465), the Northwestern Atlantic (ODP Site 1049), the Gulf of Mexico and the Tethys: The Benthic Foraminiferal Record, Palaeogeography, Palaeoclimatology, Palaeoecology (2005)
Uppermost Maastrichtian benthic foraminiferal assemblages (N 63 Am) are diverse, indicating mesotrophic conditions in lower...
Benthic Foraminiferal Faunal Turnover Across the Cretaceous/Tertiary Boundary at Agost (Southeastern Spain): Paleoenvironmental Inferences, Marine Micropaleontology (2003)
Pleistocene-Recent
Surviving mass extinction by bridging the benthic/planktic divide (with Kate F. Darling, Simone A. Kasemann, Heidi A. Seears, Christopher W. Smart, and Christopher M. Wade), Proc. Natl. Acad. Sci. USA (2009)
Evolution of planktic organisms from benthic ancestors is commonly thought to represent unidirectional expansion into...
Balancing the Deglacial Global Carbon Budget: The Hydrate Factor, Quarternary Science Reviews (2003)
Productivity Control of Fine Particle Transport to Equatorial Pacific Sediment, Global Biogeochemical Cycles (2000)
Paleocene-Eocene and Greenhouse World
Surviving mass extinction by bridging the benthic/planktic divide (with Kate F. Darling, Simone A. Kasemann, Heidi A. Seears, Christopher W. Smart, and Christopher M. Wade), Proc. Natl. Acad. Sci. USA (2009)
Evolution of planktic organisms from benthic ancestors is commonly thought to represent unidirectional expansion into...
Cenozoic Mass Extinctions in the Deep Sea; What Disturbs the Largest Habitat on Earth?, Geological Society of America Special Paper (2007)
Deep-sea benthic foraminifera live in the largest habitat on Earth, constitute an important part of...