Pacific rats trace 2,000 years of human impact on island ecosystems

Chemical analysis of the remains of rats from archaeological sites spanning the last 2,000 years on three Polynesian island systems has shown the impact that humans have had on local environments. The analysis by an international team of scientists allowed the researchers to reconstruct the rats’ diets — and through them the changes made by humans to local ecosystems, including native species extinctions and changes to food webs and soil nutrients.