CANBERRA, AUSTRALIA—Scientists estimate that some 1,000 species of birds were eradicated when humans migrated into the Pacific region. The plump, flightless birds had evolved on the islands without major predators, and probably became an easy food source for humans. Those that weren’t eaten may have lost their habitats to land clearing practices. Conservation ecologist Richard Duncan of the University of Canberra and his team developed a statistical model to estimate the number of undiscovered, extinct, non-perching land birds that may have been lost by comparing the fossil record to species that are still alive today. “The proportion of living birds that we know are missing from the fossil record gives you an idea of how many extinct species are [also] missing,” he said. The team concludes that roughly ten percent of the world’s bird species were lost.