Biology & Paleo Environment Events
For upcoming seminars, see our calendar here.
Our new seminar day and time: Mondays at 12 pm, Comer Seminar Room
"A New View of Old Landscapes: Paleovegetation from Molecular Biomarkers
in East African Paleosols"
Geochemical data from terrestrial and marine sedimentary archives have greatly advanced our understanding of how African climate changed across key junctures in human evolution. An outstanding and significant challenge to investigating the role of climate in human evolution has been a lack of paleovegetation records from the same terrestrial sediments that host hominin fossils and therefore represent local ecological conditions. I apply the novel approach of measuring carbon isotope ratios from plant wax biomarkers in fossil soils, or paleosols, to reconstruct vegetation in the fossil-rich Lower Omo Valley in Ethiopia from 3.7 to 1.1 Ma. The new leaf wax isotope data yield two key results. The first is a significant increase in C4 grasses around 2.8 Ma, which is coincident with a major shift in faunal composition and in the diets of several mammalian lineages. This demonstrates a direct effect of vegetation change on fauna. Second, superimposed over a secular trend toward increased C4 biomass through time are frequent large swings in vegetation, possibly driven by orbital cyclicity. Landscape variability documented in the leaf wax isotope data provide evidence for highly variable environmental conditions that have been proposed as a critical selective pressure in human evolution.
- SPECIAL SEMINAR: Wednesday August 27th @ 11:00 am, Comer Seminar Room, Dr. Fulvio Boatta, University of Palermo. Visiting scientist at LDEO. Host: Joaquim Goes
- Monday September 8, 12 pm: Dr. Chris Brierley, UCL. "Pliocene Tropical Dynamics." Host: Peter deMenocal.
- Monday September 15, 12 pm: Jessica Moerman, PhD Student at Georgia Tech, "Improving tropical paleoclimate interpretations by monitoring modern water isotopes". Host: Maureen Raymo
- Monday September 22, 12 pm: Sloan Coats, PhD Candidate LDEO
- Monday September 29, 12 pm: Dr. Natalie Burls, Postdoctoral Associate, Yale, "A cloud albedo control on ocean temperature gradients and implications for early Pliocene warmth". Host: Heather Ford
- Monday October 6, 12 pm: Dr. Carly Buchwald, WHOI. Host: Kim Popendorf "Nitrogen cycling in the primary and secondary nitrite maxima of the Costa Rica Upwelling Dome."
- Monday October 13, 12 pm: Dr. Liz Corbett, Postdoctoral Research Fellow, LDEO. Host: Dorothy Peteet. "Quantifying the Microbial Utilization of Methanogenesis and Methane Loss from Northern Wetlands"
- Monday October 20, 12 pm: Tammo Reichgelt, PhD student, University of Otago, New Zealand, "Seasonal climatic gradients of Early Miocene New Zealand". Host: Billy d'Andrea
- Monday October 27, 12 pm: Dr. Paola Moffa Sanchez, Postdoctoral fellow, Rutgers University. Host: Billy d'Andrea
- Monday November 3, 12 pm: Dr. Kevin Uno, Postdoctoral Research Fellow, LDEO. Host: Peter deMenocal
- Monday November 10, 12 pm: Dr. Bethany Jenkins, Associate Professor, University of Rhode Island. Hosts: Hugh Ducklow and Sonya Dyhrman.
- Monday November 17, 12 pm: Dr. Heather Graham, Postdoctoral Fellow, NASA/GSFC. Host: Pratigya Polissar.
- Monday November 24, 12 pm: Dr. Etienne Boucher, Professor, Department of Geography and GEOTOP, Université du Québec à Montréal. "Data-model fusion in dendroclimatology: general ideas, applications, and research perspectives." Host: Laia Andreu
Additional talks can be seen on the