Diversification and extinction in the history of life

Science

Volumn 268, Issue 5207, 1995, Pages 52-58

  Benton, M J ^a  

^a UNIVERSITY OF BRISTOL   (United Kingdom)

Author keywords

[No Author keywords available]

Indexed keywords

ALGAE; ANIMALIA; ENTOVALVA; FUNGI; PROTISTA;

ANIMAL; ARTICLE; EVOLUTION; GENETIC SELECTION; PALEONTOLOGY; POPULATION DYNAMICS;

ANIMAL; EVOLUTION; PALEONTOLOGY; POPULATION DYNAMICS; SELECTION (GENETICS); SUPPORT, NON-U.S. GOV'T;

DIVERSITY; EXTINCTION; TEMPORAL VARIATION;

EID: 0029638366     PISSN: 00368075     EISSN: None     Source Type: Journal    
DOI: 10.1126/science.7701342     Document Type: Article

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47. J. J. Sepkoski Jr., Milw. Public Mus. Contrib. Biol. Geol. 51, 1 (1982); ibid. 83, 1 (1992).
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49. M. J. Benton, Mem. Soc. Geol. Fr. 150, 21 (1987); Philos. Trans. R. Soc. London Ser. B 325, 369 (1989); in Palaeontology and Evolution, D. E. G. Briggs and K. C. Allen, Eds. (Belhaven, London, 1989), pp. 218-241.
50. M. J. Benton, Mem. Soc. Geol. Fr. 150, 21 (1987); Philos. Trans. R. Soc. London Ser. B 325, 369 (1989); in Palaeontology and Evolution, D. E. G. Briggs and K. C. Allen, Eds. (Belhaven, London, 1989), pp. 218-241.
51. M. J. Benton, Mem. Soc. Geol. Fr. 150, 21 (1987); Philos. Trans. R. Soc. London Ser. B 325, 369 (1989); in Palaeontology and Evolution, D. E. G. Briggs and K. C. Allen, Eds. (Belhaven, London, 1989), pp. 218-241.
52. E. Jarzembowski and A. Ross, Geol. Today 9, 218 (1993); C. C. Labandeira and J. J. Sepkoski Jr., Science 261, 310 (1993).
53. E. Jarzembowski and A. Ross, Geol. Today 9, 218 (1993); C. C. Labandeira and J. J. Sepkoski Jr., Science 261, 310 (1993).
54. The only complete overview of the history of life, The Fossil Record [W. B. Harland et al., Eds. (Geological Society of London, London, 1967)], was not used extensively for studies of diversification and mass extinction, partly because it did not provide uniform coverage of all taxa (some groups were treated at the family level, but many were listed at the level of the order), and partly because it was perceived as out of date by the 1980s, when large-scale statistical analysis of the fossil record became commonplace.
55. M. J. Benton, Ed., The Fossil Record 2 (Chapman and Hall, London, 1993).
56. Data in The Fossil Record 2 are not entirely uniform in their presentation. Data were not listed to the family level for some groups of scorpions, Paleozoic crinoids, and asterozoans. Stratigraphic data are also rather coarse for some groups, including Foraminrfera and pre-Tertiary insects. Certain groups, including some problematic Paleozoic arthropods, are entirely omitted. Likewise, in a small number of cases, relevant experts were not available to complete compilations, and those affected chapters were completed by the editor. These technical problems affect about 10% of The Fossil Record 2 database, and they arose because of the usual logistical problems in completing a large compilaton of data. Only future checking will demonstrate whether these problems affect the macroevolutionary conclusions, although experience suggests [see (75, 76)] that they probably will not.
57. In the analyses reported here, data were coded as far as possible according to the intentions of the authors of each chapter. Hence, definite and questioned age assignments were distinguished. The minimum measure includes only families recorded as definitely present within each stratigraphic stage or as definitely spanning that stage, and only families designated as restricted solely to the marine or continental realm. The maximum measure also includes all doubtful stratigraphic attributions of families and all equivocal and shared habitat designations. The sum of the minimum measures for continental and marine organisms is equal to the minimum measure for all taxa together, but the sums of the maximum measures do not equal the maximum measure for all taxa, because families with equivocal environmental assignments and those which occur in both marine and continental settings are counted as both marine and continental.
58. Minimum and maximum estimates of diversity differ to a varying extent at different times. Most of the divergence between minimum and maximum diversity estimates in the continental (Fig. 1B) and marine (Fig. 1C) plots during the Cenozoic arises from the 100 or so families that certainly, or probably, occupied both marine and terrestrial realms. Such families were excluded from the minimum estimates of diversity, but they were included in the maximum estimates. Another major source of difference between both estimates arises from questionable dates of origin and extinction of families. This is particularly acute for continental records, where many insect families have stratigraphically imprecise dates of origin, and where palynological and whole-plant records of angiosperms differ substantially.
59. P. D. Ward, Geol. Soc. Am. Spec. Pap. 247, 425 (1990).
60. Geological time scales are based on W. B. Harland et al., A Geologic Time Scale 1990 (Cambridge Univ. Press, Cambridge, 1990).
61. M. Foote, Paleobiology 20, 424 (1994); J. J. Sepkoski Jr. and K. F. Koch, in Bio-Events and Event Stratigraphy, O. Walliser, Ed. (Springer-Verlag, Berlin, in press).
62. M. Foote, Paleobiology 20, 424 (1994); J. J. Sepkoski Jr. and K. F. Koch, in Bio-Events and Event Stratigraphy, O. Walliser, Ed. (Springer-Verlag, Berlin, in press).
63. I thank all contributors to The Fossil Record 2 and M. Benton for compiling the data into a computer-usable format. Also, many thanks to J. Sepkoski and an anonymous referee for their helpful comments on this article. This work was partially supported by the Leverhulme Trust, and compilation of the data was supported by the Royal Society, the Linnean Society (National Environment Research Council Taxonomic Publications Fund), and the Palaeontological Association. The data are available in electronic form through the World Wide Web (http://www.gly.bris.ac.uk/www/research/ palaeo/palaeo.html).