Appendix S1 Details of population data.

Appendix S2 Climate data.

Appendix S3 Setting of cooling and warming thresholds.

Appendix S4 Data concerning the direct triggers of population collapses.

Appendix S5 Details of population collapse incidents in the Northern Hemisphere, 800–1900.

Appendix S6 The average duration of war in the Northern Hemisphere.

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GEB_625_sm_AppendixS5.doc221KSupporting info item
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