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A growing number of molecular fossils are common and abundant in many Cretaceous and Tertiary sediments, but rare in older sediments.  The observed spatial and temporal distribution of the biomarker oleanane (and the widespread occurrence of functionalized oleanoids in living monocots and eudicots) has led to oleanane’s use as a qualitative indicator of angiosperm input in sediments.  Other potential molecules include des-A-oleanane (a putative byproduct of oleanane), and bicadinanes (known from dimerization and diagenesis of sesquiterpenoids in resinites from Dipterocarpaceae).  However, more precise interpretations of oleanane occurrence are limited by incomplete taxonomic surveys for oleanoid natural products in living angiosperms and other seed plants.  In particular, basal-most angiosperms had not been sampled.  To examine oleanoid distribution in the base of the angiosperm tree, we sample species from the three most basal orders, Amborellales, Nymphaeales and Austrobaileyales, as well as Chloranthales, Magnoliales, Laurales, Piperales, Acorales, Alismatales, Ceratophyllales and Ranunculales.  Living material was collected, identified and air dried.  Half the sample was mounted as a voucher and the other half was crushed and cut into small fragments for analysis.  The samples were then subjected to hydrous pyrolysis, extracted, hydrogenated using an ionic reduction procedure, and separated into saturate and aromatic fractions.  The presence of appropriate functionalized natural products was tested using GCMS and GC-MRM-MS techniques.  The procedure was designed to mimic conditions of diagenesis and burial which transforms diverse functionalized natural products into a limited number of identifiable molecular fossils.  Oleanoids were found in the most basal orders and a parsimony reconstruction supports the hypothesis that they are ancestral to angiosperms.  The two diagenetic transformation products, oleanane and des-A-oleanane, have similar distributions but des-A-oleanane is more easily measured in plant pyrolysates. This distribution is not surprising as oleanane and des-A-oleanane occurrence have been correlated (correlation coefficient 1.0) in a 100+ oil-sample set derived from source rocks of a wide variety of geologic ages and depositional environments.  Lastly, basal angiosperms do not seem to be a direct source for bicadinanes, supporting previous work showing low correlation to oleanane source rock occurrence, and suggesting they are usually the result of diagenesis and restructuring of existing sesquiterpenoid.  This project has involved colleagues at Stanford University as well as a recent graduate that work as an undergraduate, and new undergraduate.  During this grant period the first undergraduate was a coauthor on a second published abstract.  Although she has a job, I am including her in the process of writing the manuscript.  The second graduate student has been working do literature searches to see if we can identify other potential biomarkers by looking at the chemistry of living organisms.  She has gain much in her understanding of biogeochemistry and should be presenting her results this fall.  The funding was important for me as a provided me with the ability to have samples analyzed and to continue a long term collaboration on plant molecular fossils.  The project has made steady progress in the second of three reporting periods.  This includes analysis of additional samples, confirmation analysis of the original samples, and attendance at several meetings, trips to obtain samples.  We have also gathered several other types of data to support the des-A oleanane results.  Due to delays with equipment, the first manuscript has been delayed and we anticipate an initial submission of a manuscript by the next reporting period.