DavidKeys.com

The human family tree just became even more complicated. Scientists have discovered genetic evidence of two previously unknown human lineages hidden within the DNA of people living today. Unlike Neanderthals and Denisovans, these mysterious ancestors have never been identified from a sequenced genome. Instead, researchers worked backward from the DNA of modern humans to uncover evidence that our ancestors repeatedly encountered and interbred with other human groups. The findings, published in the journal Science, suggest that human evolution was not...Click for full post

For centuries, scientists have imagined a vacuum as the ultimate form of nothingness—a region completely devoid of matter, particles and activity. But modern physics has long suggested that the vacuum of space may be far stranger than it appears. Now, astronomers studying one of the most extreme objects in the universe may have found the strongest evidence yet that empty space can actually change the way light travels. The discovery centers on a bizarre quantum phenomenon known as vacuum birefringence,...Click for full post

Imagine standing in a forest 165 million years ago. Dinosaurs may have been moving through the vegetation, but they weren't the only animals making noise. High above the forest floor and among the plants, ancient cricket and katydid relatives were producing calls that may have filled the Jurassic night. Now, scientists have reconstructed what some of those 165-million-year-old Jurassic insect sounds may have been like. The research, published in the Proceedings of the National Academy of Sciences, combines fossil evidence...Click for full post