Outlook grim for mammals and birds.

• Position: Ecology - Brief article

The ongoing global growth in the human population inevitably crowds out mammals and birds and has the potential to threaten hundreds of species with extinction within 40 years, maintains research in Human Ecology. Scientists have determined that the average growing nation should expect at least 3.3% more threatened species in the next decade and an increase of 10.8% species threatened with extinction by 2050. The U.S. ranks sixth in the world in the number of new species expected to be threatened by 2050.

"The data speaks loud and clear that not only human population density, but the growth of the human population, is still having an effect on extinction threats to other species," says anthropologist Jeffrey McKee, lead author of the study.

The findings suggest that any truly meaningful biodiversity conservation efforts must take the expanding human population...