title: "Tertius gaudens": germplasm exchange networks and agroecological knowledge among home gardeners in the Iberian Peninsula.
abstract: BACKGROUND
  The idea that knowledge flows through social networks is implicit in research on traditional knowledge, but researchers have paid scant attention to the role of social networks in shaping its distribution. We bridge those two bodies of research and investigate a) the structure of network of exchange of plant propagation material (germplasm) and b) the relation between a person's centrality in such network and his/her agroecological knowledge.
  
  
  METHODS
  We study 10 networks of germplasm exchange (n = 363) in mountain regions of the Iberian Peninsula. Data were collected through participant observation, semi-structured interviews, and a survey.
  
  
  RESULTS
  The networks display some structural characteristics (i.e., decentralization, presence of external actors) that could enhance the flow of knowledge and germplasm but also some characteristics that do not favor such flow (i.e., low density and fragmentation). We also find that a measure that captures the number of contacts of an individual in the germplasm exchange network is associated with the person's agroecological knowledge.
  
  
  CONCLUSIONS
  Our findings highlight the importance of social relations in the construction of traditional knowledge.
authors.affiliation: ICREA and Institut de Ciència i Tecnologia Ambientals, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain.
authors.forename: Victoria
authors.initials: V
authors.lastname: Reyes-García
authors.forename: José Luis
authors.initials: JL
authors.lastname: Molina
authors.forename: Laura
authors.initials: L
authors.lastname: Calvet-Mir
authors.forename: Laura
authors.initials: L
authors.lastname: Aceituno-Mata
authors.forename: Juan J
authors.initials: JJ
authors.lastname: Lastra
authors.forename: Ricardo
authors.initials: R
authors.lastname: Ontillera
authors.forename: Montse
authors.initials: M
authors.lastname: Parada
authors.forename: Manuel
authors.initials: M
authors.lastname: Pardo-de-Santayana
authors.forename: Montse
authors.initials: M
authors.lastname: Rigat
authors.forename: Joan
authors.initials: J
authors.lastname: Vallès
authors.forename: Teresa
authors.initials: T
authors.lastname: Garnatje
mesh_terms: D000383:Agriculture; D017753:Ecosystem; D005260:Female; D006801:Humans; D019359:Knowledge; D008297:Male; D012944:Social Support; D013030:Spain