![]() Insolation cycles as a major control of equatorial Indian Ocean primary production. Orbitally forced climate signals in mid-Pliocene nannofossil assemblages. Decrease in coccolithophore calcification and CO 2 since the middle Miocene. Reduced continental weathering and marine calcification linked to late Neogene decline in atmospheric CO 2. Calcareous nannoplankton evolution: a tale of two oceans. Extreme Lewontin’s paradox in ubiquitous marine phytoplankton species. Coccolithophore size rules-reconstructing ancient cell geometry and cellular calcite quota from fossil coccoliths. Journal of Nannoplankton Research, Special Issue 1, 1–132 (2003). A guide to extant coccolithophore taxonomy. The role of the global carbonate cycle in the regulation and evolution of the Earth system. ![]() The colonization of the oceans by calcifying pelagic algae. Ratio of coccolith CaCO 3 to foraminifera CaCO 3 in late Holocene deep sea sediments. PISCES-v2: an ocean biogeochemical model for carbon and ecosystem studies. IPSL-CM5A2-an Earth System Model designed for multi-millennial climate simulations. Northern Hemisphere climate regimes during the past 3 Ma: possible tectonic connections. Repeated species radiations in the recent evolution of the key marine phytoplankton lineage Gephyrocapsa. The Gephyrocapsa sea surface palaeothermometer put to the test: comparison with alkenone and foraminifera proxies off NW Africa. Sensitivity of coccolithophores to carbonate chemistry and ocean acidification. We recommend that you refer to the project website: for a proper installation and compilation of the environment.īeaufort, L. The login/password combination requested at first use to download the ORCHIDEE component is anonymous/anonymous. branches/publications/ORCHIDEE_IPSLCM5A2.1.r53 and OASIS3-MCT 2.0_branch (rev 4775 IPSL server). The mod.def file provides information regarding the different revisions used, namely: NEMOGCM branch nemo_v3_6_STABLE revision 6665 XIOS2 branchs/xios-2.5 revision 1763 IOIPSL/src svn tags/v2_2_2 LMDZ5 branches/IPSLCM5A2. IPSL-CM5A2 source code is publicly available through svn, with the following commands line : svn co modipsl cd modipsl/util. OASIS-MCT is released under the terms of the Lesser GNU General Public License (LGPL). LMDZ, XIOS, NEMO and ORCHIDEE are released under the terms of the CeCILL license. We posit that eccentricity pacing of phytoplankton evolution contributed to the strong 405,000-year cyclicity that is seen in global carbon cycle records.Īll coccolith morphological data, as well as all model outputs described in the paper (including NPP and main oceanic and atmospheric variables) are archived at the SEANOE open access data repository. Reduced seasonality in surface ocean conditions favours species with mid-size coccoliths, increasing coccolith carbonate export and burial whereas enhanced seasonality favours a larger range of coccolith sizes and reduced carbonate export. Simulations with an Earth System Model 5 coupled with an ocean biogeochemical model 6 show a strong eccentricity modulation of the seasonal cycle, which we suggest directly affects the diversity of ecological niches that occur over the annual cycle in the tropical ocean. Here, using high-resolution coccolith data, we show that during the last 2.8 million years the morphological evolution of coccolithophores was forced by Earth’s orbital eccentricity with rhythms of around 100,000 years and 405,000 years-a distinct spectral signature to that of coeval global climate cycles 4. Evolutionary genetic analyses have linked broad changes in Pleistocene fossil coccolith morphology to species radiation events 3. The fossil remains of coccolithophores, a key calcifying phytoplankton group, enable a detailed assessment of the effect of cyclic orbital-scale climate changes on evolution because of their abundance in marine sediments and the preservation of their morphological adaptation to the changing environment 1, 2. Although the role of Earth’s orbital variations in driving global climate cycles has long been recognized, their effect on evolution is hitherto unknown.
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