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Body size downgrading of mammals over the late Quaternary

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Science  20 Apr 2018:
Vol. 360, Issue 6386, pp. 310-313
DOI: 10.1126/science.aao5987
  • Fig. 1 Distribution of body size selectivity coefficients over the Cenozoic mammal record.

    All selectivity coefficients reflect change in the natural logarithm of the odds of extinction associated with a one-log10-unit change in body mass. Values of zero indicate no bias, positive values indicate bias against larger size, and negative values indicate bias against smaller size. LQ, average of all late Quaternary (LP to H) extinctions; LP, late Pleistocene; EP, end Pleistocene; TP, terminal Pleistocene; H, Holocene; and F, future extinctions.

  • Fig. 2 Analyses of size bias in the mammalian fossil record.

    (A and B) Global patterns of extinction. (A) Difference in the mean of log-transformed sizes of victims versus survivors for intervals across the late Quaternary. (B) Selectivity coefficients measuring the association between body size and extinction probability derived from logistic regression of extinction status as a function of body mass. Multiple regressions controlling for the additive contributions of continental location and trophic guild yield even stronger associations between extinction status and body mass (table S5) (21). (C and D) Extinction patterns on each continent. (C) Size differences. (D) Size selectivity coefficients. (E and F) Influence of trophic guild on extinction risk. (E) Size differences. (F) Size selectivity coefficients. Bars indicate 95% confidence interval (CI).

  • Fig. 3 Body size and its influence on extinction risk.

    (A) Global mean body size over the Cenozoic (65 to 1 Ma ago). (B) Mean body size by continent over the late Quaternary (past 125 ka). (C) Maximum body size across the Cenozoic by continent. (D) Maximum body size over the late Quaternary and into the future. (E) Size selectivity coefficients across the entire Cenozoic fossil record. (F) Size selectivity of late Quaternary extinctions. Bars indicate 95% CI. All masses are in kilograms. Light blue shading indicates late Pleistocene, white shading indicates Holocene, and gray shading indicates the future (+200 years). Ages here and elsewhere are plotted as midpoint of time interval.

  • Fig. 4 The body size distribution of terrestrial, nonvolant mammals on each continent over the late Quaternary.

    (A) Africa. (B) Eurasia. (C) Australia. (D) North America. (E) South America. Body sizes for each temporal interval are plotted; distributions are overlaid from oldest to youngest. Yellow shading indicates the predicted distribution in the future, if vulnerable species go extinct.

Supplementary Materials

  • Body size downgrading of mammals over the late Quaternary

    Felisa A. Smith, Rosemary E. Elliott Smith, S. Kathleen Lyons, Jonathan L. Payne

    Materials/Methods, Supplementary Text, Tables, Figures, and/or References

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    • Materials and Methods 
    • Figs. S1 to S4
    • Tables S1 to S7 
    • References 

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