Biogeographic network analysis of South American Ephemeroptera

DOMÍNGUEZ, E.; MOLINERI, C.; NIETO, C. & DOS SANTOS, D.

Stuttgart, Alemania

Congreso; XII International Conference on Ephemeroptera; 2008

Staatliches Museum fur Naturkunde

There are several theoretical and methodological problems in the current procedures used to propose hypotheses of simpatry and determination of the basic units of biogeography. The current methods assume sympatry by distributional co-ocurrence into predefined spatial units(generally square grids). These procedures are especially unsuitable for the study of riverine organisms, whose distributions are coupled with the linear and convoluted trajectory of the rivers they inhabit. We present here, exemplified with South American Ephemeroptera data, a method recently developed. This new method is capable of deriving sympatry hypotheses from dot maps, without appealing to a grid pre-processing of records. Then, these sympatry hypotheses are submitted to a network analysis, from where isolated groups of sympatric species (units of co-occurrence) are extracted. The areas occupied by these units become the candidates to aeas of endemism.