Pii: S0025-5564(99)00054-1

Multi-species Lotka±Volterra models exhibit greater instability with an increase in diversity and/or connectance. These model systems, however, lack the likely behavior that a predator will prey more heavily on some species if other prey species decline in relative abundance. We ®nd that stability does not depend on diversity and/or connectance in multi-species Lotka±Volterra models with this `predator switching'. This conclusion is more consistent with several empirical observations than the classic conclusion, suggesting that large complex ecosystems in nature may be more stable than previously supposed. Ó 2000 Elsevier Science Inc. All rights reserved.