The document discusses improvements made to the conventional species-area model (SAM) for predicting biodiversity loss due to changes in habitat area. The conventional SAM assumes habitat loss fragments are completely inhospitable and does not account for edge effects between habitat and surrounding land. The improved "matrix-calibrated species-area model" (MC SAM) accounts for how species respond to the composition and quality of surrounding land and the effects of habitat edges. When tested against data, the MC SAM was over 13 times more strongly supported than the next best model.