Evaluate the collective function of references cited together in a given text segment.
Classify their combined role into one of the following categories: 'method', 'background', or 'result'.

Text:2000; Bush & de Oliveira 2006) because it has been recognized that Tertiary Neogene tectonic and palaeogeographical reorganization have also been important drivers of the origin of Neotropical (Pennington et al. 2004; Hoorn et al. 2010; Rull 2011) and temperate biodiversity (Quiroga & Premoli 2010; S ersic et al.
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