crops, to guide field logistics, and to formulate national research and conservation strategies (Asfaw et al., 1990). The ground surveys following this preparatory work led to the discovery of new sites and important new fossils.

There are a variety of satellite and aerial imagery techniques available that would aid in locating probable fossiliferous areas. These could be applied in a hierarchical sequence, with lower resolution but broader scale satellite analyses to identify promising areas (Figure 4.1A) being succeeded by progressively more focused and higher resolution satellite3 and aerial imagery. Ultimately, we envision very high resolution multispectral imagery, perhaps collected by Unmanned Aerial Vehicles (UAVs) configured for civilian scientific research (Figure 4.1B). Enhancing discovery at the other end of the spectrum—actually finding hominin fossils—requires trained eyes to scan the surface of fossiliferous sediments for suitable fossils (Figure 4.1C). This component of the process can be optimized by an increase in the number of skilled observers, who would ideally be trained people from the particular country of research.

As a consequence of various human impacts (e.g., settlement), hominin fossils are a severely diminishing resource. Existing sites are being depleted, and are largely nonrenewable because of the long time periods needed for material to weather out from the subsurface (e.g., White, 2004). It is crucially important that an enhanced exploration program be carried out soon, before vital information about our deep past history and its relation to climatic change vanishes completely. This program of work cannot be deferred, or the results will diminish significantly.

This proposed venture will inject into the process of discovery a major multidisciplinary initiative to finance extensive remote sensing operations for the detection of new fossiliferous areas and sites, and to promote a substantially enhanced program of ground exploration. One outcome will be to redress the narrow focus that has resulted from relatively small, individual research groups tending to return to well-known areas and regions where the potential for success is thought to be highest. In Africa, for example, it will extend the range of exploration well beyond the confines of the Rift Valley. The initiative proposed here will greatly increase the potential for the discovery of new fossiliferous regions, new sites, and new information about human ancestry. Integrating these data with

3

MODIS (Moderate Resolution Imaging Spectroradiometer) has a resolution of about 250 m to a pixel, or about 500 m in color, and such data are suitable for producing large-scale base maps. Elevation maps from the SRTM (Shuttle Radar Topography Mission) are resolvable to 90 m, and these data permit slopes and aspect to be calculated. LANDSAT, to be supplemented by the Landsat Data Continuity Mission (LDCM) from summer 2011, has provided great coverage since 1972 with a resolution of 20-30 m per pixel. These data are not only more finely resolved, but provide the advantage of enabling land cover classification. ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) is still higher resolution (15 m, or 30 m in color). ASTER also permits the analysis of shortwave bands that are suitable for distinguishing different minerals, and hence provides potential to identify rock types. There are also higher resolution systems—ALOS (Advanced Land Observing Satellite) can resolve to 10 m in color; IKONOS can resolve from 3.2 m to 82 cm; and QUICKBIRD is advertised as achieving a pixel resolution of 61 cm in panchromatic bands.



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