FIGURE 3.1 Synthesis of global deep-sea benthic foraminiferal oxygen isotope records, based on analyses of cores from Deep Sea Drilling Program and Ocean Drilling Program sites, updated with high-resolution records for the interval spanning the middle Eocene to the middle Miocene. Raw data were smoothed using a 5-point running mean. The conversion of oxygen isotope data to a temperature scale was computed for an ice-free ocean, and therefore only applies to the portion of the curve older than about 35 Ma. Note the strong cooling trend, with only minor perturbations, over the past 8 Ma. SOURCE: Modified from Zachos et al. (2008).

FIGURE 3.1 Synthesis of global deep-sea benthic foraminiferal oxygen isotope records, based on analyses of cores from Deep Sea Drilling Program and Ocean Drilling Program sites, updated with high-resolution records for the interval spanning the middle Eocene to the middle Miocene. Raw data were smoothed using a 5-point running mean. The conversion of oxygen isotope data to a temperature scale was computed for an ice-free ocean, and therefore only applies to the portion of the curve older than about 35 Ma. Note the strong cooling trend, with only minor perturbations, over the past 8 Ma. SOURCE: Modified from Zachos et al. (2008).

Straits of Gibraltar, and the Indonesia seaway). Despite this broad understanding of the history of global environmental change, there is limited understanding of the regional environments in which hominins evolved, and an incomplete understanding of the processes that have forced these global and regional climatic and environmental changes over the past 8 Ma.

Did climate change shape human evolution, and if so, how? As noted above, there is now evidence that several major junctures in human evolution and behavior were coincident with fundamental changes in global and regional climate. As intriguing as these temporal coincidences are, demonstrating a causal linkage between them is a much more challenging and intensive task. This chapter defines a set of research activities that will develop the paleoclimatic, paleoanthropological, and archaeological observations needed to test hypotheses linking climatic and biotic change that encompass the major events in hominin evolution. A range of potential research topics and initiatives to clarify the relationships and interactions between these evolutionary and environmental histories were advanced by the wider community during the open workshop held as part of this study. The committee assessed these topics, and identified the following two high-priority research themes as having the greatest potential to transform our understanding of the origin of human adaptations to environmental change.



The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement