Uncategorized
- Earth
Only a third of Earth’s longest rivers still run free
Mapping millions of kilometers of waterways shows that just 37 percent of rivers longer than 1,000 kilometers remain unchained by human activities.
- Archaeology
Ancient South American populations dipped due to an erratic climate
Scientists link bouts of intense rainfall and drought around 8,600 to 6,000 years ago to declining numbers of South American hunter-gatherers.
- Health & Medicine
50 years ago, scientists tried to transplant part of a human eye
In 1969, a doctor tried and failed to restore a 54-year-old man’s vision. Fifty years later, scientists are still struggling to make eye transplants work.
