carbon dioxide emissions

Worldwide efforts to protect plant and animal species may not be enough to avoid a mass extinction in the face of unexpected climate changes and global warming, says an international team of researchers. While the Earth’s climate is never stable, natural records of the past — such as fossils, ice cores, corals, and lake sediments — reveal that the species and ecosystems of today evolved within a specific range of climate conditions. The scientists are concerned that human activities, such as increased carbon dioxide emissions into the atmosphere, may push the climate outside of its current range, with devastating impacts on species around the globe.