Western Equatorial Pacific Middle Miocene Fohsellid Stable Isotope Data ----------------------------------------------------------------------- World Data Center for Paleoclimatology, Boulder and NOAA Paleoclimatology Program ----------------------------------------------------------------------- NOTE: PLEASE CITE CONTRIBUTORS WHEN USING THIS DATA!!!!! NAME OF DATA SET: Western Equatorial Pacific Middle Miocene Fohsellid Stable Isotope Data LAST UPDATE: 7/2006 (Original receipt by WDC Paleo) CONTRIBUTOR: D. Clay Kelly, University of Wisconsin. IGBP PAGES/WDCA CONTRIBUTION SERIES NUMBER: 2006-067 SUGGESTED DATA CITATION: Eisenach, A.R. and D.C. Kelly. 2006. Western Equatorial Pacific Middle Miocene Fohsellid Stable Isotope Data. IGBP PAGES/World Data Center for Paleoclimatology Data Contribution Series # 2006-067. NOAA/NCDC Paleoclimatology Program, Boulder CO, USA. ORIGINAL REFERENCE: Eisenach, A.R. and D.C. Kelly. 2006. Coiling Preferences and Evolution in the Middle Miocene Fohsella Chronocline. Marine Micropaleontology, in press. ABSTRACT: Micropaleontologists have traditionally recognized the mid-Miocene Fohsella lineage as a flagship for phyletic gradualism within the planktic foraminifera. However, study of a deep-sea record from the western equatorial Pacific (ODP Site 806B) reveals that coiling ratios within this clade suddenly (<5 kyr) shift after a prolonged, ancestral state of near randomness (~50%) to a transient phase (13.42 – 13.43 Ma) of dextral dominance (~75%) immediately following the first common occurrence of keeled fohsellids. This brief period of dextral dominance was abruptly (<5 kyr) succeeded by an irreversible change to sinistral dominance (~96%). Fohsellid abundances decline markedly through the interval in which the sinistral preference is established. The shift to sinistrality (13.42 Ma) predated the deepening of fohsellid depth ecology by ~240 – 488 kyr, indicating that these two events were unrelated. This view is supported by a lack of d18O evidence for depth-habitat differences between the two chiral forms, which refutes the notion that sinistral fohsellids were "pre-adapted" for ensuing hydrographic change because they occupied a deeper depth habitat than their dextral counterparts. Planktic foraminiferal assemblages become strongly oligotrophic in character through the interval in which the fohsellid d18O increase is recorded, indicating that the migration to deeper depths was fostered by an expansion of the mixed layer in the western equatorial Pacific. Salient aspects of this brief, but conspicuous faunal change are a marked increase in the abundance of symbiont-bearing globigerinoidids, a concomitant collapse of local Jenkinsella mayeri/siakensis populations, and reduced fohsellid abundances. The rapid and permanent nature of the Fohsella sinistral shift provides a distinct, unequivocal datum that may prove useful for correlating mid-Miocene sections throughout the Caribbean Sea and tropical regions in the western sectors of the Pacific and Atlantic. The coiling ratio changes that occurred during the evolution of the Fohsella chronocline probably reflect changing population dynamics between cryptic genotypes or demes with opposite coiling preferences. GEOGRAPHIC REGION: Western equatorial Pacific Ocean PERIOD OF RECORD: ~13-12 MMYrBP DESCRIPTION: Middle Miocene fohsellid stable isotope data across the dextral to sinistral dominance transition. ODP Site 806B, atop Ontong Java Plateau: 0°19.11’ N, 159°21.69’ E; 2519 m water depth DATA: Table 2. Stable isotope data for fohsellids from ODP Site 806B. Column 1: Hole Column 2: Core-Section Column 3: Interval (cm) Column 4: Age Column 5: Depth, Meters below seafloor Column 6: Species. R = dextrally-coiled, L = sinistrally-coiled, praefsi= praefohsi, Column 7: Mass mg. Column 8: d13C Column 8: d18O Hole C-Sec. Int. Age Mbsf Species Mass d13C d18O 806B 45H-06 55 12.402 424.64 fohsi-R 29 1.334 -0.898 806B 45H-06 55 12.402 424.64 fohsi-R 34 1.678 -0.498 806B 45H-06 55 12.402 424.64 fohsi-L 37 1.546 -0.877 806B 45H-06 55 12.402 424.64 fohsi-L 34 1.72 -0.548 806B 45H-06 55 12.402 424.64 fohsi-L 42 1.524 -1.104 806B 45H-06 55 12.402 424.64 fohsi-L 52 1.63 -0.632 806B 45H-06 55 12.402 424.64 fohsi-L 36 1.696 -0.594 806B 45H-06 55 12.402 424.64 robusta-L 55 1.441 -0.427 806B 45H-06 55 12.402 424.64 robusta-L 56 1.54 -0.855 806B 45H-06 55 12.402 424.64 robusta-L 50 1.475 -0.944 806B 46H-02 101 12.579 428.51 robusta-R 58 1.635 -0.823 806B 46H-02 101 12.579 428.51 robusta-R 51 1.48 -1.209 806B 46H-02 101 12.579 428.51 fohsi-L 40 1.623 -0.775 806B 46H-02 101 12.579 428.51 fohsi-L 44 1.455 -0.825 806B 46H-02 101 12.579 428.51 fohsi-L 50 1.696 -0.573 806B 46H-02 101 12.579 428.51 fohsi-L 39 1.528 -0.906 806B 46H-02 101 12.579 428.51 fohsi-L 42 1.663 -0.796 806B 46H-02 101 12.579 428.51 fohsi-L 51 1.584 -0.727 806B 46H-02 101 12.579 428.51 robusta-L 67 1.579 -0.94 806B 46H-02 101 12.579 428.51 robusta-L 71 1.565 -0.838 806B 46H-02 101 12.579 428.51 robusta-L 50 1.699 -0.746 806B 46H-02 101 12.579 428.51 robusta-L 55 1.636 -0.631 806B 46H-05 5 12.741 432.04 fohsi-R 42 1.418 -0.426 806B 46H-05 5 12.741 432.04 fohsi-R 33 1.545 -0.409 806B 46H-05 5 12.741 432.04 robusta-R 61 1.436 0.265 806B 46H-05 5 12.741 432.04 robusta-R 54 1.547 -0.069 806B 46H-05 5 12.741 432.04 robusta-R 53 1.57 -0.911 806B 46H-05 5 12.741 432.04 fohsi-L 30 1.435 -0.724 806B 46H-05 5 12.741 432.04 fohsi-L 36 1.443 -0.476 806B 46H-05 5 12.741 432.04 fohsi-L 32 1.604 -0.873 806B 46H-05 5 12.741 432.04 fohsi-L 31 1.423 -0.611 806B 46H-05 5 12.741 432.04 fohsi-L 36 1.279 -0.662 806B 46H-05 5 12.741 432.04 fohsi-L 32 1.45 -0.768 806B 46H-05 5 12.741 432.04 fohsi-L 26 1.389 -0.499 806B 46H-05 5 12.741 432.04 fohsi-L 42 1.621 -0.636 806B 46H-05 5 12.741 432.04 fohsi-L 44 1.641 -0.428 806B 46H-05 5 12.741 432.04 fohsi-L 45 1.45 -0.792 806B 46H-05 5 12.741 432.04 fohsi-L 45 1.667 -0.659 806B 46H-05 5 12.741 432.04 robusta-L 45 1.426 -0.785 806B 46H-05 5 12.741 432.04 robusta-L 54 1.424 -0.496 806B 46H-05 5 12.741 432.04 robusta-L 67 1.34 -0.718 806B 46H-05 5 12.741 432.04 robusta-L 61 1.51 -0.713 806B 46H-05 5 12.741 432.04 robusta-L 56 1.703 -0.571 806B 46H-05 5 12.741 432.04 robusta-L 60 1.351 -0.619 806B 46H-05 5 12.741 432.04 robusta-L 55 1.528 -0.483 806B 46H-05 5 12.741 432.04 robusta-L 60 1.512 -0.912 806B 46H-05 5 12.741 432.04 robusta-L 62 1.599 -0.94 806B 46H-05 5 12.741 432.04 robusta-L 57 1.468 -0.975 806B 46H-05 5 12.741 432.04 robusta-L 61 1.546 -0.879 806B 46H-06 3 12.808 433.52 fohsi-R 34 1.271 -1.158 806B 46H-06 3 12.808 433.52 fohsi-R 35 1.708 -0.623 806B 46H-06 3 12.808 433.52 fohsi-R 24 1.686 -0.402 806B 46H-06 3 12.808 433.52 robusta-R 50 1.711 -0.791 806B 46H-06 3 12.808 433.52 robusta-R 38 1.56 -0.718 806B 46H-06 3 12.808 433.52 robusta-R 50 1.795 -0.666 806B 46H-06 3 12.808 433.52 robusta-R 58 1.755 -0.38 806B 46H-06 3 12.808 433.52 robusta-R 60 1.748 -0.825 806B 46H-06 3 12.808 433.52 fohsi-L 43 1.713 -1.045 806B 46H-06 3 12.808 433.52 robusta-L 50 1.791 -0.374 806B 46H-06 3 12.808 433.52 robusta-L 56 1.766 -0.893 806B 46H-06 3 12.808 433.52 robusta-L 53 1.725 -0.853 806B 46H-06 3 12.808 433.52 robusta-L 51 1.785 -0.799 806B 46H-06 3 12.808 433.52 robusta-L 41 1.882 -0.309 806B 46H-06 3 12.808 433.52 robusta-L 53 1.707 -0.293 806B 46H-06 3 12.808 433.52 robusta-L 57 1.794 -0.846 806B 46H-06 126 12.865 434.76 fohsi-R 35 1.726 -0.238 806B 46H-06 126 12.865 434.76 fohsi-R 22 1.695 -0.595 806B 46H-06 126 12.865 434.76 fohsi-L 27 1.821 -0.088 806B 46H-06 126 12.865 434.76 fohsi-L 34 1.799 -0.53 806B 46H-06 126 12.865 434.76 fohsi-L 47 1.634 -0.531 806B 46H-06 126 12.865 434.76 fohsi-L 33 1.811 -0.665 806B 46H-06 126 12.865 434.76 fohsi-L 34 1.85 -0.607 806B 46H-06 126 12.865 434.76 robusta-L 41 1.651 -0.772 806B 46H-06 126 12.865 434.76 robusta-L 45 1.839 -0.637 806B 46H-06 126 12.865 434.76 robusta-L 42 1.748 -0.457 806B 46H-06 126 12.865 434.76 robusta-L 71 1.621 -0.853 806B 47H-02 55 12.993 437.55 fohsi-R 35 1.811 -0.466 806B 47H-02 55 12.993 437.55 fohsi-R 30 1.577 -0.972 806B 47H-02 55 12.993 437.55 fohsi-R 32 1.513 -0.695 806B 47H-02 55 12.993 437.55 fohsi-R 41 1.608 -0.988 806B 47H-02 55 12.993 437.55 fohsi-R 50 1.597 -0.734 806B 47H-02 55 12.993 437.55 robusta-R 60 1.602 -1.073 806B 47H-02 55 12.993 437.55 robusta-R 54 1.628 -0.968 806B 47H-02 55 12.993 437.55 fohsi-L 51 1.689 -0.881 806B 47H-02 55 12.993 437.55 fohsi-L 42 1.704 -1.073 806B 47H-02 55 12.993 437.55 fohsi-L 44 1.673 -0.965 806B 47H-02 55 12.993 437.55 robusta-L 49 1.598 -0.837 806B 47H-02 55 12.993 437.55 robusta-L 40 1.632 -0.533 806B 47H-02 55 12.993 437.55 robusta-L 56 1.578 -1.12 806B 47H-02 55 12.993 437.55 robusta-L 59 1.78 -0.874 806B 47H-02 55 12.993 437.55 robusta-L 52 1.759 -1.088 806B 48H-01 126 13.179 443.65 praefsi-R 28 1.658 -1.125 806B 48H-01 126 13.179 443.65 praefsi-R 21 1.646 -0.506 806B 48H-01 126 13.179 443.65 praefsi-R 18 1.446 -1.093 806B 48H-01 126 13.179 443.65 praefsi-R 20 1.591 -1.259 806B 48H-01 126 13.179 443.65 praefsi-R 19 1.655 -0.743 806B 48H-01 126 13.179 443.65 praefsi-R 18 1.832 -0.983 806B 48H-01 126 13.179 443.65 praefsi-R 22 1.645 -1.268 806B 48H-01 126 13.179 443.65 praefsi-R 19 1.655 -0.541 806B 48H-01 126 13.179 443.65 fohsi-R 37 1.65 -1.193 806B 48H-01 126 13.179 443.65 fohsi-R 42 1.695 -1.002 806B 48H-01 126 13.179 443.65 fohsi-R 34 1.874 -1.343 806B 48H-01 126 13.179 443.65 fohsi-R 38 1.794 -1.152 806B 48H-01 126 13.179 443.65 praefsi-L 56 1.831 -0.798 806B 48H-01 126 13.179 443.65 praefsi-L 60 1.735 0.07 806B 48H-01 126 13.179 443.65 praefsi-L 55 1.467 -1.156 806B 48H-01 126 13.179 443.65 praefsi-L 60 1.678 -0.99 806B 48H-01 126 13.179 443.65 praefsi-L 62 1.61 -0.95 806B 48H-01 126 13.179 443.65 praefsi-L 57 1.812 -1.175 806B 48H-01 126 13.179 443.65 praefsi-L 61 1.377 -1.135 806B 48H-01 126 13.179 443.65 praefsi-L 29 1.731 -0.948 806B 48H-01 126 13.179 443.65 praefsi-L 31 1.711 -0.907 806B 48H-01 126 13.179 443.65 praefsi-L 38 1.64 -1.077 806B 48H-01 126 13.179 443.65 praefsi-L 30 1.562 -1.101 806B 48H-01 126 13.179 443.65 fohsi-L 36 1.749 -1.281 806B 48H-01 126 13.179 443.65 fohsi-L 32 1.55 -0.835 806B 48H-01 126 13.179 443.65 fohsi-L 31 1.896 -1.194 806B 48H-01 126 13.179 443.65 fohsi-L 32 1.846 -1.103 806B 48H-01 126 13.179 443.65 fohsi-L 32 1.739 -1.179 806B 48H-01 126 13.179 443.65 fohsi-L 27 1.731 -0.708 806B 48H-01 126 13.179 443.65 fohsi-L 45 1.785 -0.68 806B 48H-01 126 13.179 443.65 fohsi-L 61 1.489 -0.798 806B 48H-01 126 13.179 443.65 fohsi-L 54 1.706 -0.913 806B 49H-01 53 13.323 452.72 praefsi-R 20 1.253 -1.995 806B 49H-01 53 13.323 452.72 praefsi-R 17 1.182 -1.779 806B 49H-01 53 13.323 452.72 fohsi-R 23 1.516 -1.524 806B 49H-01 53 13.323 452.72 fohsi-R 22 1.785 -1.302 806B 49H-01 53 13.323 452.72 fohsi-R 35 1.605 -0.874 806B 49H-01 53 13.323 452.72 fohsi-R 27 1.524 -1.218 806B 49H-01 53 13.323 452.72 fohsi-R 23 1.819 -1.18 806B 49H-01 53 13.323 452.72 praefsi-L 22 1.528 -1.571 806B 49H-01 53 13.323 452.72 praefsi-L 24 1.351 -1.956 806B 49H-01 53 13.323 452.72 praefsi-L 25 1.536 -0.875 806B 49H-01 53 13.323 452.72 praefsi-L 18 1.565 -0.974 806B 49H-01 53 13.323 452.72 praefsi-L 17 1.494 -0.969 806B 49H-01 53 13.323 452.72 praefsi-L 20 1.761 -1.699 806B 49H-01 53 13.323 452.72 fohsi-L 24 1.678 -1.291 806B 49H-01 53 13.323 452.72 fohsi-L 30 1.672 -1.199 806B 49H-01 53 13.323 452.72 fohsi-L 25 1.64 -1.349 806B 49H-01 53 13.323 452.72 fohsi-L 34 1.871 -1.212 806B 49H-01 53 13.323 452.72 fohsi-L 22 1.109 -1.36 806B 49H-01 53 13.323 452.72 fohsi-L 19 1.523 -1.8 806B 49H-05 78 13.423 458.97 praefsi-R 22 1.769 -0.747 806B 49H-05 78 13.423 458.97 praefsi-R 25 1.508 -0.853 806B 49H-05 78 13.423 458.97 praefsi-R 23 1.509 -0.902 806B 49H-05 78 13.423 458.97 praefsi-R 24 1.813 -0.912 806B 49H-05 78 13.423 458.97 praefsi-R 22 2.105 -0.869 806B 49H-05 78 13.423 458.97 praefsi-R 23 1.674 -0.778 806B 49H-05 78 13.423 458.97 praefsi-R 22 1.432 -0.947 806B 49H-05 78 13.423 458.97 praefsi-R 23 1.718 -1.01 806B 49H-05 78 13.423 458.97 praefsi-R 22 1.453 -1.171 806B 49H-05 78 13.423 458.97 praefsi-R 29 1.365 -1.667 806B 49H-05 78 13.423 458.97 praefsi-R 22 1.841 -1.016 806B 49H-05 78 13.423 458.97 praefsi-R 23 1.417 -1.159 806B 49H-05 78 13.423 458.97 praefsi-R 25 1.887 -0.744 806B 49H-05 78 13.423 458.97 praefsi-R 21 1.489 -0.615 806B 49H-05 78 13.423 458.97 praefsi-R 20 1.659 -0.817 806B 49H-05 78 13.423 458.97 praefsi-R 21 1.587 -0.808 806B 49H-05 78 13.423 458.97 praefsi-R 24 1.732 -1.129 806B 49H-05 78 13.423 458.97 fohsi-R 23 1.683 -0.954 806B 49H-05 78 13.423 458.97 fohsi-R 25 1.704 -0.828 806B 49H-05 78 13.423 458.97 fohsi-R 28 1.812 -0.969 806B 49H-05 78 13.423 458.97 fohsi-R 30 1.583 -1.028 806B 49H-05 78 13.423 458.97 fohsi-R 27 1.878 -1.049 806B 49H-05 78 13.423 458.97 fohsi-R 24 1.668 -0.591 806B 49H-05 78 13.423 458.97 fohsi-R 28 1.566 -1.129 806B 49H-05 78 13.423 458.97 fohsi-R 20 1.619 -0.882 806B 49H-05 78 13.423 458.97 fohsi-R 17 1.63 -0.902 806B 49H-05 78 13.423 458.97 fohsi-R 25 1.678 -0.801 806B 49H-05 78 13.423 458.97 fohsi-R 20 1.495 -0.926 806B 49H-05 78 13.423 458.97 praefsi-L 20 1.67 -0.684 806B 49H-05 78 13.423 458.97 praefsi-L 23 1.796 -0.482 806B 49H-05 78 13.423 458.97 praefsi-L 23 1.658 -1.084 806B 49H-05 78 13.423 458.97 praefsi-L 22 1.342 -0.895 806B 49H-05 78 13.423 458.97 praefsi-L 26 1.808 -0.863 806B 49H-05 78 13.423 458.97 praefsi-L 22 1.377 -0.772 806B 49H-05 78 13.423 458.97 fohsi-L 27 1.794 -0.879 806B 49H-05 78 13.423 458.97 fohsi-L 28 1.735 -0.986 806B 49H-05 78 13.423 458.97 fohsi-L 26 1.924 -0.917 806B 49H-05 78 13.423 458.97 fohsi-L 28 1.751 -0.902 806B 49H-05 78 13.423 458.97 fohsi-L 25 1.665 -0.888 806B 49H-05 78 13.423 458.97 fohsi-L 22 1.904 -0.876 806B 49H-05 126 13.43 459.45 praefsi-R 22 1.689 -1.012 806B 49H-05 126 13.43 459.45 praefsi-R 16 1.643 -0.881 806B 49H-05 126 13.43 459.45 praefsi-R 21 1.75 -0.96 806B 49H-05 126 13.43 459.45 praefsi-R 25 1.819 -1.197 806B 49H-05 126 13.43 459.45 praefsi-R 27 1.658 -0.853 806B 49H-05 126 13.43 459.45 praefsi-R 19 1.976 -0.69 806B 49H-05 126 13.43 459.45 praefsi-R 23 1.723 -0.829 806B 49H-05 126 13.43 459.45 praefsi-R 19 1.819 -0.986 806B 49H-05 126 13.43 459.45 praefsi-R 18 1.671 -1.358 806B 49H-05 126 13.43 459.45 praefsi-R 22 1.806 -1.174 806B 49H-05 126 13.43 459.45 praefsi-R 26 1.593 -0.931 806B 49H-05 126 13.43 459.45 praefsi-R 29 1.985 -0.941 806B 49H-05 126 13.43 459.45 praefsi-R 20 1.751 -1.115 806B 49H-05 126 13.43 459.45 praefsi-R 27 1.637 -0.988 806B 49H-05 126 13.43 459.45 fohsi-R 21 1.91 -0.591 806B 49H-05 126 13.43 459.45 fohsi-R 24 1.811 -0.872 806B 49H-05 126 13.43 459.45 fohsi-R 24 1.754 -0.917 806B 49H-05 126 13.43 459.45 fohsi-R 24 1.871 -1.058 806B 49H-05 126 13.43 459.45 fohsi-R 27 1.981 -1.152 806B 49H-05 126 13.43 459.45 fohsi-R 23 1.778 -0.884 806B 49H-05 126 13.43 459.45 fohsi-R 30 1.91 -1.06 806B 49H-05 126 13.43 459.45 fohsi-R 29 1.613 -0.94 806B 49H-05 126 13.43 459.45 fohsi-R 20 1.683 -0.75 806B 49H-05 126 13.43 459.45 fohsi-R 26 1.791 -0.861 806B 49H-05 126 13.43 459.45 fohsi-R 21 1.77 -0.977 806B 49H-05 126 13.43 459.45 fohsi-R 30 1.805 -1.202 806B 49H-05 126 13.43 459.45 fohsi-R 24 1.691 -1.046 806B 49H-05 126 13.43 459.45 fohsi-R 23 1.762 -1.07 806B 49H-05 126 13.43 459.45 fohsi-R 19 1.771 -0.709 806B 49H-05 126 13.43 459.45 fohsi-R 28 1.702 -0.887 806B 49H-05 126 13.43 459.45 fohsi-R 19 1.888 -0.596 806B 49H-05 126 13.43 459.45 fohsi-R 19 1.697 -1.021 806B 49H-05 126 13.43 459.45 fohsi-R 19 2.068 -0.646 806B 49H-05 126 13.43 459.45 fohsi-R 22 1.842 -0.932 806B 49H-05 126 13.43 459.45 fohsi-R 19 1.946 -0.782 806B 49H-05 126 13.43 459.45 fohsi-R 30 1.74 -1.104 806B 49H-05 126 13.43 459.45 fohsi-R 19 1.835 -0.705 806B 49H-05 126 13.43 459.45 fohsi-R 29 1.599 -0.89 806B 49H-05 126 13.43 459.45 praefsi-L 20 1.919 -1.101 806B 49H-05 126 13.43 459.45 praefsi-L 24 1.884 -0.902 806B 49H-05 126 13.43 459.45 praefsi-L 21 1.984 -0.887 806B 49H-05 126 13.43 459.45 praefsi-L 26 2.044 -1.127 806B 49H-05 126 13.43 459.45 praefsi-L 24 1.657 -0.982 806B 49H-05 126 13.43 459.45 praefsi-L 24 2.219 -1.201 806B 49H-05 126 13.43 459.45 praefsi-L 27 1.858 -1.119 806B 49H-05 126 13.43 459.45 fohsi-L 27 1.87 -0.965 806B 49H-05 126 13.43 459.45 fohsi-L 21 1.882 -0.631 806B 49H-05 126 13.43 459.45 fohsi-L 25 2.066 -1.304 806B 49H-05 126 13.43 459.45 fohsi-L 24 1.941 -1.091 806B 49H-05 126 13.43 459.45 fohsi-L 28 1.722 -0.953 806B 49H-05 126 13.43 459.45 fohsi-L 24 1.892 -0.403 806B 49H-05 126 13.43 459.45 fohsi-L 27 1.881 -1.201 806B 49H-05 126 13.43 459.45 fohsi-L 26 1.843 -0.725 806B 49H-05 126 13.43 459.45 fohsi-L 17 1.7 -1.008 806B 49H-05 126 13.43 459.45 fohsi-L 20 1.942 -1.144