EXTINCTION FILTERS AND CURRENT RESILIENCE - THE SIGNIFICANCE OF PAST SELECTION PRESSURES FOR CONSERVATION BIOLOGY

There is now little reasonable doubt about the scale of the present ex tinction crisis: recent and ongoing rates of species loss exceed backg round levels by two to three orders of magnitude. Nevertheless, specie s differ widely in their vulnerability to current threats. Growing evi dence from both palaeontology and conservation biology suggests that p ast events may help to explain this variation. Communities appear far more resilient to particular threats if they have faced similar challe nges in the past. This intuitive but poorly reported phenomenon has po tentially far-reaching implications for attempts to focus conservation efforts on those areas most at risk from contemporary human activity.