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The Probable Datum Method (PDM): a technique for estimating the age of origination or extinction of nannoplankton

Published online by Cambridge University Press:  08 April 2016

Jonathan D. Schueth
Department of Geosciences, Pennsylvania State University, University Park, Pennsylvania 16802, U.S.A. E-mail:
Klaus Keller
Department of Geosciences and Earth and Environmental Systems Institute, Pennsylvania State University, University Park, Pennsylvania 16802, U.S.A., and Department of Engineering and Public Policy, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, U.S.A.
Timothy J. Bralower
Department of Geosciences, Pennsylvania State University, University Park, Pennsylvania 16802, U.S.A. E-mail:
Mark E. Patzkowsky
Department of Geosciences, Pennsylvania State University, University Park, Pennsylvania 16802, U.S.A. E-mail:
E-mail address:


Accurate interpretation of origination and extinction of fossil species is crucial to answering a variety of questions in paleontology. Fossil datums, the observed age of first or last occurrences, are subject to sampling error as a result of preservation and low abundances near range endpoints. This sampling error can cause local range offset, an age difference between the observed first or last occurrence of a species and its true origination or extinction. Here, we develop and test a new technique, the Probable Datum Method (PDM), that can be used to assess the extent of local range offset for nannofossil species. The PDM estimates the original abundance of a taxon and its probable true age of first or last occurrence. The PDM uses a model in which original abundance is related to count abundance through preservation and the counting process. This model is empirically parameterized, including an experimental determination of false positive and error rates of a nannofossil count. The model is simulated then inverted to estimate likely original abundance and true datum age from count abundance data. We first test the PDM in a positive control experiment with known parameter values. This experiment shows that the PDM is robust and returns known values accurately. Next we apply the method to the origination of nannoplankton after the Cretaceous/Paleogene boundary to test whether first occurrences were synchronous between widely spaced locations. The PDM results suggest that observed diachrony of K/Pg originations cannot be explained by the effects of local range offset; rather, in some cases they indicate truly diachronous first occurrences between localities. Although the technique was developed to analyze nannoplankton ranges, the statistical nature of the PDM, its experimentally derived parameters, and its parsimonious nature should make it applicable to many micropaleontological studies that interpret patterns of origination and extinction.

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Alegret, L., Molina, E., and Thomas, E. 2003. Benthic foraminiferal turnover across the Cretaceous/Tertiary boundary at Agost (southeastern Spain): paleoenvironmental inferences. Marine Micropaleontology 48:251279.CrossRefGoogle Scholar
Alroy, J. 2001. A multispecies overkill simulation of the end-Pleistocene megafaunal mass extinction. Science 292:18931896.CrossRefGoogle ScholarPubMed
Andronova, N. G., and Schlesinger, M. E. 2001. Objective estimation of the probability density function for climate sensitivity. Journal of Geophysical Research 106:2260522611.CrossRefGoogle Scholar
Andruleit, H. 1996. A filtration technique for quantitative studies of coccoliths. Micropaleontology 42:403406.CrossRefGoogle Scholar
Andruleit, H. 1997. Coccolithophore fluxes in the Norwegian–Greenland Sea: seasonality and assemblage alterations. Marine Micropaleontology 31:4564.CrossRefGoogle Scholar
Arenillas, I., Arz, J. A., Molina, E., and Dupuis, C. 2000. An independent test of planktic foraminiferal turnover across the Cretaceous/Paleogene (K/P) boundary at El Kef, Tunisia: catastrophic mass extinction and possible survivorship. Micropaleontology 46:3149.Google Scholar
Backman, J., and Raffi, I. 1997. Calibration of Miocene nannofossil events to orbitally tuned cyclostratigraphies from Ceara Rise. InShackleton, N. J., Curry, W. B., Richter, C., and Bralower, T. J., eds. Proceedings of the Ocean Drilling Program, Scientific Results 154:8399.Google Scholar
Backman, J., and Shackleton, N. J. 1983. Quantitative biochronology of Pliocene and early Pleistocene calcareous nannofossils from the Atlantic, Indian, and Pacific oceans. Marine Micropaleontology 8:141170.CrossRefGoogle Scholar
Baker, P. A., Gieskes, J. M., and Elderfield, H. 1982. Diagenesis of carbonates in deep-sea sediments: evidence from Sr/Ca ratios and interstitial dissolved Sr2+ data. Journal of Sedimentary Petrology 52:7182.Google Scholar
Baumann, K.-H., Andruleit, H., Böckel, B., Geisen, M., and Kinkel, H. 2005. The significance of extant coccolithophores as indicators of ocean water masses, surface water temperature, and paleoproductivity: a review. Paläontologische Zeitschrift 79:93112.CrossRefGoogle Scholar
Beaufort, L. 1991. Adaptation of the random settling method for quantitative studies of calcareous nannofossils. Micropaleontology 37:415418.CrossRefGoogle Scholar
Berger, W. H. 1975. Dissolution of deep-sea carbonates: an introduction. Journal of Foraminiferal Research Special Publication 13:710.Google Scholar
Berger, W. H. 1978. Sedimentation of deep-sea carbonate: maps and models of variations and fluctuations. Journal of Foraminiferal Research 8:286302.CrossRefGoogle Scholar
Berger, W. H., and Winterer, E. L. 1974. Plate stratigraphy and the fluctuating carbonate line. InHsü, K. J. and Jenkyns, H. C., eds. Pelagic sediments: on land and under the sea. Blackwell Publishing, Oxford.Google Scholar
Bernaola, G., and Monechi, S. 2007. Calcareous nannofossil extinction and survivorship across the Cretaceous/Paleogene boundary at Walvis Ridge (ODP Hole 1262C, South Atlantic Ocean). Palaeogeography, Palaeoclimatology, Palaeoecology 255:132156.CrossRefGoogle Scholar
Bleiweiss, R. 1998. Fossil gap analysis supports early Tertiary origin of trophically diverse avian orders. Geology 26:323326.2.3.CO;2>CrossRefGoogle Scholar
Bollman, J., Brabec, B., Cortés, M. Y., and Geisen, M. 1999. Determination of absolute coccolith abundances in deep-sea sediments by spiking with microbeads and spraying (SMS-method). Marine Micropaleontology 48:2938.CrossRefGoogle Scholar
Bown, P. 2005. Selective calcareous nannoplankton survivorship at the Cretaceous/Tertiary boundary. Geology 33:653656.CrossRefGoogle Scholar
Bown, P. R., and Young, J. R. 1998. Techniques. Pp. 1628inBown, P. R., ed. Calcareous nannofossil biostratigraphy. Kluwer Academic, Boston.CrossRefGoogle Scholar
Bown, P. R., Lees, J. A., and Young, J. R. 2004. Calcareous nannoplankton evolution and diversity through time. Pp. 481508inThierstein, H. R. and Young, J. R., eds. Coccolithophores: from molecular processes to global impact. Springer, New York.CrossRefGoogle Scholar
Bramlette, M. N. 1961. Pelagic sediments. InSears, M., ed. Oceanography. American Association of the Advancement of Sciences Publication 67:345366.Google Scholar
Broecker, W. S., and Peng, T.-H. 1982. Tracers in the sea. Lamont-Doherty Geological Observatory, Palisades, N.Y.Google Scholar
Broecker, W. S., 1987. The role of CaCO3 compensation in the glacial to interglacial atmospheric CO2 change. Global Biogeochemical Cycles 1:1529.CrossRefGoogle Scholar
Broecker, W. S., and Takahashi, T. 1977. The solubility of calref in seawater. Pp. 365379inGraser, D. G., ed. Thermodynamics in geology. Reidel, Dordrecht.CrossRefGoogle Scholar
Bross, I. 1954. Misclassification in 2 × 2 tables. Biometrics 10:478486.CrossRefGoogle Scholar
Coccioni, R., and Marsili, A. 2007. The response of benthic foraminifera to the K/Pg boundary biotic crisis at Elles (northwestern Tunisia). Palaeogeography, Palaeoclimatology, Palaeoecology 255:157180.CrossRefGoogle Scholar
Davis, J. C. 2002. Statistics and data analysis in geology, 3rd ed. Wiley, New York.Google Scholar
Ehrendorfer, T., and Aubry, M-P. 1992. Calcareous nannoplankton changes across the Cretaceous/Paleocene boundary in the southern Indian Ocean (Site 750). InWise, S. W., Schlich, R., et al., eds. Proceedings of the Ocean Drilling Program, Scientific Results 120:451470.Google Scholar
Erba, E., Bottini, C., Weissert, H. J., and Keller, C. E. 2010. Calcareous nannoplankton response to surface water acidification around anoxic event 1a. Science 329:428432.CrossRefGoogle ScholarPubMed
Fantle, M. S., and DePaolo, D. J. 2006. Sr isotopes and pore fluid chemistry in carbonate sediment of the Ontong Java Plateau: calref recrystallization rates and evidence for rapid rise in seawater Mg over the last 10 million years. Geochimica et Cosmochimica Acta 70:38833904.CrossRefGoogle Scholar
Fantle, M. S., Maher, K. M., and DePaolo, D. J. 2010. Isotopic approaches for quantifying the rates of marine burial diagenesis. Reviews of Geophysics 48:138.CrossRefGoogle Scholar
Foote, M. 1997. The evolution of morphological diversity. Annual Review of Ecology and Systematics 28:129152.CrossRefGoogle Scholar
Fuqua, L. M., Bralower, T. J., Arthur, M. A., and Patzkowsky, M. E. 2008. Evolution of calcareous nannoplankton and the recovery of marine food webs after the Cretaceous–Paleogene mass extinction. Palaios 23:185194.CrossRefGoogle Scholar
Gibbs, S. J., Young, J. R., Bralower, T. J., and Shackleton, N. J. 2005. Nannofossil evolutionary events in the mid-Pliocene: an assessment of the degree of synchrony in the extinctions of Reticulofenestra pseudoumbilicus and Sphenolithus abies. Palaeogeography, Palaeoclimatology, Palaeoecology 217:155172.CrossRefGoogle Scholar
Hageman, S. J. 1992. Alternative methods for dealing with nonnormality and heteroscedasticity in paleontological data. Journal of Paleontology 66:857867.CrossRefGoogle Scholar
Hales, B. 2003. Respiration, dissolution, and the lysocline. Paleoceanography 18:1099.CrossRefGoogle Scholar
Heath, G. R., and Culberson, C. 1970. Calref: degree of saturation, rate of dissolution, and the compensation depth in the deep oceans. Geological Society of America Bulletin 81:31573160.CrossRefGoogle Scholar
Henrich, R., and Wefer, G. 1986. Dissolution of biogenic carbonates: effects of skeletal structure. Marine Geology 71:341362.CrossRefGoogle Scholar
Holland, S. M. 1995. The stratigraphic distribution of fossils. Paleobiology 21:92109.CrossRefGoogle Scholar
Holland, S. M. 2003. Confidence limits on fossil ranges that account for facies changes. Paleobiology 29:468479.2.0.CO;2>CrossRefGoogle Scholar
Holland, S. M., and Patzkowsky, M. E. 1999. Models for simulating the fossil record. Geology 27:491494.2.3.CO;2>CrossRefGoogle Scholar
Holland, S. M., 2002. Stratigraphic variation in the timing of first and last occurrences. Palaios 17:134146.2.0.CO;2>CrossRefGoogle Scholar
Honjo, S. 1976. Coccoliths: production, transportation and sedimentation. Marine Micropaleontology 1:6579.CrossRefGoogle Scholar
Hüneke, H., and Henrich, R. 2011. Pelagic sedimentation in modern and ancient oceans. Pp. 215352inHüneke, H. and Mulder, T., eds. Deep-sea sediments. Elsevier, Oxford.CrossRefGoogle Scholar
Jahnke, R. A., and Jahnke, D. B. 2004. Calcium carbonate dissolution in deep sea sediments: reconciling microelectrode, pore water, and benthic flux chamber results. Geochimica et Cosmochimica Acta 68:4759.CrossRefGoogle Scholar
Jaynes, E. T. 2003. Probability theory: the logic of science. Cambridge University Press, Cambridge.CrossRefGoogle Scholar
Jiang, S., Bralower, T. J., Patzkowsky, M. E., Kump, L. R., and Schueth, J. D. 2010. Geographic controls on nannoplankton extinction across the Cretaceous/Paleogene boundary. Nature Geosciences 3:280285.CrossRefGoogle Scholar
Jin, Y. G., Wang, Y., Wang, W., Shang, Q. H., Cao, C. Q., and Erwin, D. H. 2000. Pattern of marine mass extinction near the Permian/Triassic boundary in South China. Science 289:432436.CrossRefGoogle Scholar
Kalb, A. K., and Bralower, T. J. 2012. Nannoplankton origination events and environmental changes in the late Paleocene and early Eocene. Marine Micropaleontology 92–93:115.CrossRefGoogle Scholar
Keller, G., Stinnesbeck, W., Adatte, T., and Stüben, D. 2003. Multiple impacts across the Cretaceous/Tertiary boundary. Earth-Science Reviews 62:327363.CrossRefGoogle Scholar
Keller, G., Adatte, T., Berner, Z., Harting, M., Baum, G., Prauss, M., Tantawy, A., and Stueben, D. 2007. Chicxulub impact predates K/T boundary: new evidence from Brazos, Texas. Earth and Planetary Science Letters 255:339356.CrossRefGoogle Scholar
Killingley, J. S. 1983. Effects of diagenetic recrystallization on 18O/16O values of deep-sea sediments. Nature 301:594597.CrossRefGoogle Scholar
Liow, L. H., Skaug, H. J., Ergon, T., and Schweder, T. 2010. Global occurrence trajectories of microfossils: environmental volatility and the rise and fall of individual species. Paleobiology 36:224252.CrossRefGoogle Scholar
Lloyd, G. T., Smith, A. B., and Young, J. R. 2011. Quantifying the deep-sea rock and fossil record bias using coccolithophores. InMcGowan, A. and Smith, A. B., eds. Comparing the geological and fossil records: implications for biodiversity studies. Geological Society of London Special Publication 358:167177.CrossRefGoogle Scholar
Marshall, C. R. 1990. Confidence intervals on stratigraphic ranges. Paleobiology 16:110.CrossRefGoogle Scholar
Marshall, C. R. 1994. Confidence intervals on stratigraphic ranges: partial relaxation of the assumption of randomly distributed fossil horizons. Paleobiology 20:459469.CrossRefGoogle Scholar
Marshall, C. R. 1997. Confidence intervals on stratigraphic ranges with nonrandom distributions of fossil horizons. Paleobiology 23:165173.CrossRefGoogle Scholar
Marshall, C. R., and Ward, P. D. 1996. Sudden and gradual molluscan extinctions in the latest Cretaceous of western European Tethys. Science 274:13601363.CrossRefGoogle ScholarPubMed
Monechi, S., Vandenberghe, N., and Alegret, L. 2013. Paleogene events, evolution and stratigraphy. Ciências da Terra 18.Google Scholar
Mullen, K. M., Ardia, D., Gil, D., Windover, D., and Cline, J. 2011. DEoptim: an R package for global optimization by differential evolution. Journal of Statistical Software 40:126.CrossRefGoogle Scholar
Newell, N. D. 1959. The nature of the fossil record. Proceedings of the American Philosophical Society 103:264285.Google Scholar
Okada, H. 1992. Use of microbeads to estimate the absolute abundance of nannofossils. International Nannoplankton Association Newsletter 14:9697.Google Scholar
Pälike, H., Lyle, M. W., Nishi, H., Raffi, I., Ridgwell, A., Gamage, K., Klaus, A., et al. 2012. A Cenozoic record of the equatorial Pacific carbonate compensation depth. Nature 488:609614.CrossRefGoogle ScholarPubMed
Patzkowsky, M. E., and Holland, S. M. 2012. Stratigraphic paleobiology: understanding the distribution of fossil taxa in time and space. University of Chicago Press, Chicago.CrossRefGoogle Scholar
Payne, J. L. 2003. Applicability and resolving power of statistical tests for simultaneous extinction events in the fossil record. Paleobiology 29:3751.2.0.CO;2>CrossRefGoogle Scholar
Petersen, L. C., and Prell, W. L. 1985. Carbonate dissolution in recent sediments of the eastern equatorial Indian Ocean: preservation patterns and carbonate loss above the lysocline. Marine Geology 64:259290.CrossRefGoogle Scholar
Pinheiro, J., Bates, D., DebRoy, S., Sarkar, D., and the R Development Core Team. 2013. nlme: linear and nonlinear mixed effects models. R package, Version 3.1–111.Google Scholar
R Development Core Team. 2013. R: a Language and environment for statistical computing. R Foundation for Statistical Computing, Vienna. Scholar
Raffi, I., Backman, J., Rio, D., and Shackleton, N. J. 1993. Plio-Pleistocene nannofossil biostratigraphy and calibration to oxygen isotope stratigraphies from Deep Sea Drilling Project Site 670 and Ocean Drilling Program Site 677. Paleoceanography 8:387408.CrossRefGoogle Scholar
Raffi, I., Backman, J., Fornaciari, E., Pälike, H., Rio, D., Lourens, L., and Hilgen, F. 2006. A review of calcareous nannofossil astrobiochronology encompassing the past 25 million years. Quaternary Science Reviews 25:31133137.CrossRefGoogle Scholar
Rea, D. K., and Lyle, M. W. 2005. Paleogene calref compensation depth in the eastern subtropical Pacific: answers and questions. Paleoceanography 20:PA1012.CrossRefGoogle Scholar
Richter, F. M. 1996. Models for the coupled Sr-sulfate budget in deep-sea carbonates. Earth and Planetary Science Letters 141:199211.CrossRefGoogle Scholar
Richter, F. M., and DePaolo, D. J. 1987. Numerical models for diagenesis and the Neogene Sr isotopic evolution of seawater from DSDP site 590B. Earth and Planetary Science Letters 83:2738.CrossRefGoogle Scholar
Richter, F. M., 1988. Diagenesis and Sr isotopic evolution of seawater using data from DSDP-590B and DSDP-575. Earth and Planetary Science Letters 90:382394.CrossRefGoogle Scholar
Richter, F. M., and Liang, Y. 1993. The rate and consequences of Sr diagenesis in deep-sea carbonates. Earth and Planetary Science Letters 117:553565.CrossRefGoogle Scholar
Samtleben, C., and Schröder, A. 1992. Living coccolithophore communities in the Norwegian–Greenland Sea and their record in sediments. Marine Micropaleontology 19:333354.CrossRefGoogle Scholar
Sayles, F. L. 1979. Composition and diagenesis of interstitial solutions. I. Fluxes across the seawater-sediment interface in the Atlantic Ocean. Geochimica et Cosmochimica Acta 43:527545.CrossRefGoogle Scholar
Sayles, F. L. 1981. The composition and diagenesis of interstitial solutions. II. Fluxes and diagenesis at the water–sediment interface in the high-latitude North and South Atlantic. Geochimica et Cosmochimica Acta 45:10611086.CrossRefGoogle Scholar
Sepkoski, J. J. 1979. A kinetic model of Phanerozoic taxonomic diversity. II. Early Phanerozoic families and multiple equilibria. Paleobiology 5:222251.CrossRefGoogle Scholar
Sepkoski, J. J., and Koch, C. F. 1996. Evaluating paleontologic data relating to bio-events. Pp. 2134inWalliser, O H., ed. Global events and event stratigraphy in the Phanerozoic. Springer, Berlin.CrossRefGoogle Scholar
Shen, S., Crowley, J. L., Wang, Y., Bowring, S. A., Erwin, D. H., Sadler, P. M., Cao, C., Rothman, D. H., Henderson, C. M., Ramezani, J., Zhang, H., Shen, Y., Wang, X., Wang, W., Mu, L., Li, W., Tang, Y., Liu, X., Liu, L., Zeng, Y., Jiang, Y., and Jin, Y. 2011. Calibrating the End-Permian mass extinction. Science 334:13671372.CrossRefGoogle ScholarPubMed
Shipboard Scientific Party. 2002. Site 1210. InBralower, T. J., Premoli Silva, I., Malone, M. J., et al. Proceedings of the Ocean Drilling Program, Initial Reports 198:189.Google Scholar
Shipboard Scientific Party 2004. Site 1262. InZachos, J. C., Kroon, D., Blum, P., et al. Proceedings of the Ocean Drilling Program, Initial Reports 208:192.Google Scholar
Signor, P. W. III, and Lipps, J. H. 1982. Sampling bias, gradual extinction patterns and catastrophes in the fossil record. InSilver, L. T. and Schultz, P. H., eds. Geological implications of impacts of large asteroids and comets on the earth. Geological Society of America Special Papers 190:291296.CrossRefGoogle Scholar
Smit, J., and Hertogen, J. 1980. An extraterrestrial event at the Cretaceous/Tertiary boundary. Nature 285:198200.CrossRefGoogle Scholar
Solow, A. R. 2003. Estimation of stratigraphic ranges when fossil finds are not randomly distributed. Paleobiology 29:181185.CrossRefGoogle Scholar
Solow, A. R., and Smith, W. 1997. On fossil preservation and the stratigraphic ranges of taxa. Paleobiology 23:271277.CrossRefGoogle Scholar
Solow, A. R., Roberts, D. L., and Robbirt, K. M. 2006. On the Pleistocene extinctions of Alaskan mammoths and horses. Proceedings of the National Academy of Sciences USA 103:73517353.CrossRefGoogle ScholarPubMed
Spencer-Cervato, C. 1998. Changing depth distribution of hiatuses during the Cenozoic. Paleoceanography 13:178182.CrossRefGoogle Scholar
Spencer-Cervato, C, Thierstein, H. R., Lazarus, D. B., and Beckmann, J.-P. 1994. How synchronous are Neogene marine plankton events? Paleoceanography 9:739763.CrossRefGoogle Scholar
Sriver, R. L., Urban, N. M., Olson, R., and Keller, K. 2012. Toward a physically plausible upper bound of sea-level rise projections. Climate Change 115:893902.CrossRefGoogle Scholar
Strauss, D., and Sadler, P. M. 1987. Confidence intervals for the ends of local taxon ranges. Technical Report 158. Department of Statistics, University of California, Riverside.Google Scholar
Strauss, D., 1989. Classical confidence intervals and Bayesian probability estimates for ends of local taxon ranges. Mathematical Geology 21:411427.CrossRefGoogle Scholar
Suchéras-Marx, B., Mattiali, E., Pittet, B., Escarguel, G., and Suan, G. 2010. Astronomically paced coccolith size variations during the early Pliensbachian (Early Jurassic). Palaeogeography, Palaeoclimatology, Palaeoecology. 295:281292.CrossRefGoogle Scholar
Tenenbein, A. 1970. A double sampling scheme for estimating from binomial data with misclassifications. Journal of the American Statistical Association 65:13501361.CrossRefGoogle Scholar
Thierstein, H. R. 1979. Paleoceanographic implications of organic carbon and carbonate distribution in Mesozoic deep-sea sediments. Pp. 249274inTalwani, M., Hay, W., and Ryan, W. B. F., eds. Deep drilling results in the Atlantic Ocean: continental margins and paleoenvironment. American Geophysical Union, Washington, D.C.CrossRefGoogle Scholar
Thierstein, H. R. 1980. Selective dissolution of late Cretaceous and earliest Tertiary calcareous nannofossils: experimental evidence. Cretaceous Research 1:165176.CrossRefGoogle Scholar
Thierstein, H. R., Geitzenauer, K. R., and Molfino, B. 1977. Global synchroneity of the Late Quaternary coccolith datum levels: validation by oxygen isotopes. Geology 5:400404.2.0.CO;2>CrossRefGoogle Scholar
Thunell, R. C. 1982. Carbonate dissolution and abyssal hydrography in the Atlantic Ocean. Marine Geology 47:165180.CrossRefGoogle Scholar
Vinod, H. D. 2006. Maximum entropy ensembles for time series inference in economics. Journal of Asian Economics 17:955978.CrossRefGoogle Scholar
Vinod, H. D., and López-de-Lacalle, J. 2009. Maximum entropy bootstrap for time series: the meboot R Package. Journal of Statistical Software 29:119.CrossRefGoogle Scholar
Wang, P., Zhao, Q., Jian, Z., Cheng, X., Huang, W., Tian, J., Wang, J., Li, Q., Li, B., and Su, X. 2003. Thirty million year deep sea records in the South China Sea. Chinese Science Bulletin 48:25242535.CrossRefGoogle Scholar
Wang, S. C., and Everson, P. J. 2007. Confidence intervals for pulsed mass extinction events. Paleobiology 33:324336.CrossRefGoogle Scholar
Wang, S. C., Chudzicki, D. J., and Everson, P. J. 2009. Optimal estimators of the position of a mass extinction when recovery potential is uniform. Paleobiology 35:447459.CrossRefGoogle Scholar
Wang, S. C., Zimmerman, A. E., McVeigh, B. S., Everson, P. J., and Wong, H. 2012. Confidence intervals for the duration of mass extinction. Paleobiology 38:265277.CrossRefGoogle Scholar
Ward, P. D. 1995. After the fall: lessons and directions from the K/T debate. Palaios 10:530538.CrossRefGoogle Scholar
Wei, W., and Pospichal, J. J. 1991. Danian calcareous nannofossil succession at Site 738 in the southern Indian Ocean. InBarron, J., Larson, B., et al., eds. Proceedings of the Ocean Drilling Program, Scientific Results 119:495512.Google Scholar
Weiss, R. E., and Marshall, C. R. 1999. The uncertainty in the true end point of a fossil's stratigraphic range when stratigraphic sections are sampled discretely. Mathematical Geology 31:435453.CrossRefGoogle Scholar
Weiss, R. E., Basu, S., and Marshall, C. R. 2004. A framework for analyzing fossil record data. Pp. 215232inBuck, C. E. and Millard, A. R., eds. Tools for constructing chronologies: crossing disciplinary boundaries. Springer, London.Google Scholar
Westerhold, T., Röhl, U., Raffi, I., Fornaciari, E., Monechi, S., Reale, V., Bowles, J., and Evans, H. F. 2008. Astronomical calibration of Paleocene time. Palaeogeography, Palaeoclimatology, Palaeoecology 257:377403.CrossRefGoogle Scholar
Wilf, P., and Johnson, K. R. 2004. Land plant extinction at the end of the Cretaceous: a quantitative analysis of the North Dakota megafloral record. Paleobiology 30:347368.2.0.CO;2>CrossRefGoogle Scholar
Williams, J. R., and Bralower, T. J. 1995. Nannofossil assemblages, fine fraction stable isotopes, and the paleoceanography of the Valanginian-Barremian (Early Cretaceous) North Sea basin. Paleoceanography 10:815839.CrossRefGoogle Scholar
Zar, J. 1984. Biostatistical analysis. Prentice-Hall, Englewood Cliffs, N.J.Google Scholar

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