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Questions about the evolution of material culture are widespread in the humanities and social sciences. Statistical modeling of long-term changes in material culture is less common due to a lack of appropriate frameworks. Our goal is to close this gap and provide robust statistical methods for examining changes in the diversity of material culture. We provide an open-source and quantitative workflow for estimating rates of origination, extinction, and preservation, as well as identifying key shift points in the diversification histories of material culture. We demonstrate our approach using two distinct kinds of data: age ranges for the production of American car models, and radiocarbon dates associated with archaeological cultures of the European Neolithic. Our approach improves on existing frameworks by disentangling the relative contributions of origination and extinction to diversification. Our method also permits rigorous statistical testing of competing hypotheses to explain changes in diversity. Finally, we stress the value of a flexible approach that can be applied to data in various forms; this flexibility allows scholars to explore commonalities between forms of material culture and ask questions about the general properties of cultural change., Competing Interests: The authors have declared that no competing interests exist.

In 2005 the then ESA Directorate for Human Spaceflight, Microgravity and Exploration (D-HME) commissioned a study from the European Science Foundation's (ESF) European Space Sciences Committee (ESSC) to examine the science aspects of the Aurora Programme in preparation for the December 2005 Ministerial Conference of ESA Member States, held in Berlin. A first interim report was presented to ESA at the second stakeholders meeting on 30 and 31 May 2005. A second draft report was made available at the time of the final science stakeholders meeting on 16 September 2005 in order for ESA to use its recommendations to prepare the Executive proposal to the Ministerial Conference. The final ESSC report on that activity came a few months after the Ministerial Conference (June 2006) and attempted to capture some elements of the new situation after Berlin, and in the context of the reduction in NASA's budget that was taking place at that time; e.g., the postponement sine die of the Mars Sample Return mission. At the time of this study, ESSC made it clear to ESA that the timeline imposed prior to the Berlin Conference had not allowed for a proper consultation of the relevant science community and that this should be corrected in the near future. In response to that recommendation, ESSC was asked again in the summer of 2006 to initiate a broad consultation to define a science-driven scenario for the Aurora Programme. This exercise ran between October 2006 and May 2007. ESA provided the funding for staff support, publication costs, and costs related to meetings of a Steering Group, two meetings of a larger ad hoc group (7 and 8 December 2006 and 8 February 2007), and a final scientific workshop on 15 and 16 May 2007 in Athens. As a result of these meetings a draft report was produced and examined by the Ad Hoc Group. Following their endorsement of the report and its approval by the plenary meeting of the ESSC, the draft report was externally refereed, as is now normal practice with all ESSC-ESF reports, and amended accordingly. The Ad Hoc Group defined overarching scientific goals for Europe's exploration programme, dubbed "Emergence and co-evolution of life with its planetary environments," focusing on those targets that can ultimately be reached by humans, i.e., Mars, the Moon, and Near Earth Objects. Mars was further recognized as the focus of that programme, with Mars sample return as the recognized primary goal; furthermore the report clearly states that Europe should position itself as a major actor in defining and leading Mars sample return missions. The report is reproduced in this article. On 26 November 2008 the Ministers of ESA Member States decided to give a high strategic priority to the robotic exploration programme of Mars by funding the enhanced ExoMars mission component, in line therefore with the recommendations from this ESSC-ESF report.