Body mass patterns predict invasions and extinctions in transforming landscapes

Scale-specific patterns of resource distribution on landscapes entrain attr ibutes of-resident animal communities such that species body-mass distribut ions are organized into distinct aggregations. Species within each aggregat ion respond to resources over the same range of scale. This discontinuous p attern has predictive power: invasive species and extinct or declining spec ies in landscapes subject to human transformation tend to be located at the edge of body-mass aggregations (P < 0.01), which may be transition zones b etween distinct ranges of scale. Location at scale breaks affords species g reat opportunity, but also potential crisis.