To untangle the relationship between climate change, fall foliage and national park visitors, researchers are asking tourists to check their old photo albums for snapshots that could hold valuable data.
Many deciduous trees put on a dazzling fall foliage display. But coniferous evergreens hold on to their needles and stay green. A biologist breaks down these different survival strategies.
Global phosphate production is set to peak in 2030, around the same time the world’s population will reach nine billion. As a finite resource, a phosphate shortage will effect global food production.