Networks and Innovation: The Role of Social Assets in Explaining Firms' Innovative Capacity

The claim of a positive association between a firm's social assets and its innovative capacity is a widely debated topic in the literature. Although controversial, such an argument has informed recent innovation policy across Germany, increasingly directed to the cluster formation. In the light of the growing attention and financial efforts that cluster-based innovation policies are receiving, it is worth answering two main questions. First, are firms with a relatively high level of social capital likely to be more innovative? Secondly, do companies pursuing innovation in partnership innovate more? This paper empirically answers these questions by exploring a cross-sectoral sample of 248 firms based in the Jena region. On the one hand, the extent to which a firm is integrated in its community life does not contribute to an explanation of its innovative performance. On the other hand, directed cooperation with the specific goal of innovating shows a positive impact on innovative performance. However, the correlation between the extent of the network of co-innovators and firms' innovative capacity presents an inverted U-shaped relation: there is a threshold in the number of co-innovators justified by the costs of innovating by interacting. A policy lesson can be drawn from these findings: cluster-based policies are to be treated with caution as firms face costs of networking and not merely benefits.     

Humans,climate or introduced rats – which is to blame for the woodland destruction on prehistoric Rapa Nui (Easter Island)?

When the first Polynesian settlers arrived on Rapa Nui, about 70% of the island was covered with dense woodland in which Jubaea palms dominated. Our investigations of extended soil profiles provide evidence that more than 16 million palm trees grew on the island. Nearly all palms were removed by the 16th century. Teeth marks on nutshells of the Jubaea palms from the 13th or 14th centuries attest to the activity of Pacific rats (Rattus exulans) on Rapa Nui, which were probably imported there by the first Polynesians settlers. Did the rats perhaps prevent the germination of palm seeds and thus the regeneration of the dense palm woodland of Rapa Nui?     

Cave Art in Context: Methods for the Analysis of the Spatial Organization of Cave Sites

Investigations of prehistoric cave art have long neglected the surrounding context: space, archaeological objects, and imprints. As a result, an integrative structural approach that analyzes cave art as part of an anthropomorphized landscape has not been available. This article draws on urban planning and the physiology of the human eye to provide an innovative archaeospatial analysis of cave sites. A set of relevant features from the caves of Bédeilhac, Fontanet, and Le Portel was selected and defined (light zone, chamber type, path network, mode of movement, and available space). An analysis of the prehistoric remains in the caves allows the reconstruction of different concentrations of human activities (cave art, archaeological objects, and imprints). The projection of these concentrations onto the structured map of the caves results in four types of locations: drawing location, supply location, drawing location with substantial activities, and drawing location with consumption activities. This approach opens new avenues for the archaeological perception of caves and their inhabitants: Upper Paleolithic humans were very familiar with caves and probably followed a master plan during their stay in the dark.