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Quaternary tectonic and denudation rates are investigated for an actively growing basement anticline: the Sierra Pie de Palo range, which belongs to the Andean foreland of Northwestern Argentina (28°S–33°S). In this study, a detailed morphometric analysis of the topography is combined with in situ-produced cosmogenic10Be concentrations measured in (1) surface boulders abandoned on alluvial terraces affected by fault activity (along the north bounding fault) and growth of the basement fold (along the southeastern border), (2) bedrock outcrops corresponding to an exhumed and folded, regional erosion surface, and (3) fluvial sediments sampled at the outlets of several watersheds. Along the eastern and northern borders of the range, incision and uplift rates have been estimated at approximately 0.5 and 1 mm/yr when integrated on Holocene and Pleistocene time scales, in close agreement with both long-term (structural and basin evolution data) and short-term (GPS-derived velocity field) analyses. Cosmogenic-derived denudation and uplift rates combined with geomorphic characteristics of watersheds and river channels allows estimating the onset of the uplift at 4–6 Ma, followed by a more recent period of topographic rejuvenation at roughly 1–2 Ma, probably synchronous with steepening of the eastern and northern flanks of the anticline.

Participatory research (PR) has been analyzed and documented from different points of view, with emphasis on the benefits generated for farmers. The effect of PR on organizational learning has, however, received little attention. This paper analyzes the interaction between a research and a development institution, the International Potato Center (CIP) and CARE in Peru, respectively, and makes the case that PR can contribute to creating a collaborative learning environment among organizations. The paper describes the evolution of the inter-institutional collaborative environment between the two institutions for more than a decade, including an information-transfer period (1993–1996), an action-learning period (1997–2002), and a social-learning period (2003–2007). Several lessons learned from each period are described, as are changes in institutional contexts and stakeholders’ perceptions. The case shows that research and development-oriented organizations can interact fruitfully using PR as a mechanism to promote learning, flexibility in interactions, and innovation. Interactions foster the diffusion of information and the sharing of tacit knowledge within and between organizations, which in turn influences behavior. However, the paper also argues that long-term inter-organizational interactions are needed to facilitate learning, which can be used to influence the way organizations implement their interventions in a constantly changing environment.