Washington: The ongoing global growth in the human population has the potential to threaten hundreds of mammals and birds species with extinction within 40 years, a new study has warned.
Scientists at The Ohio State University have determined that the average growing nation should expect at least 3.3 per cent more threatened species in the next decade and an increase of 10.8 per cent species threatened with extinction by 2050.
In a previous study, researchers had created a model based on 2000 data to forecast future threatened species connected to human population growth projections, and published the predictions in 2004.
In this new study, that model`s predictions were confirmed by 2010 actual figures. The scientists then used the same model, containing data on 114 countries, to extend their predictions to the middle of this century.
"The data speak 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," said Jeffrey McKee, professor of anthropology at Ohio State and lead author of the study.
"Our projection is based on human population density alone. It doesn`t take into account climate change, industrialisation or wars. So the actual numbers that we predict for 2050 will be very different because everything we do will exacerbate the problem," he said.
McKee collected data on threatened species from the International Union for Conservation of Nature Red List, and obtained human census data for 2000 and 2010 from the world database of the US Census Bureau.
Overall species richness data came from the United Nations Environment Programme-World Conservation Monitoring Centre`s Animals of the World Database. He created a model using equations to analyse relationships among these variables.
After using 2010 data to confirm that the decade-old predictions came true, the researchers used the same equations to determine that between now and 2050, the nations that see the most population density growth will experience higher numbers of species facing new threats of extinction.
The US ranks sixth in the world in the number of new species expected to be threatened by 2050, the research found. The Democratic Republic of the Congo tops the list, with a predicted new threat to more than 20 species in that time frame.
The analysis suggests about 11 species will be newly threatened with extinction in the US.
The model also suggests that the 21 countries with projected declining human populations by 2050 will see an average reduction in threatened species of 2.5 per cent.
The study was published in the journal Human Ecology.