A quick surge of dopamine shifts mice into a dreamy stage of sleep. In the rodents’ brains, the chemical messenger triggers rapid-eye-movement sleep, or REM, researchers report in the March…
Category: Humans
How to interpret the CDC’s new mask guidelines
One moment, Campbell County in Wyoming’s northeastern corner was an area of high levels of transmission of the coronavirus, a scenario in which the U.S. Centers for Disease Control and…
How omicron’s mutations make it the most infectious coronavirus variant yet
In November, a new coronavirus variant took the world by storm. Omicron has since caused an unprecedented wave of infections, striking about 90 million people in just 10 weeks. That’s…
Fecal transplant pills helped some peanut allergy sufferers in a small trial
PHOENIX — Pills loaded with bacteria from other people’s poop might help adults who are highly allergic to peanuts safely eat the nuts in small amounts. In a small clinical…
50 years ago, freezing sperm faced scientific skepticism
The uncertainty of banking sperm – Science News, February 26, 1972 Many men contemplating vasectomies have been depositing a quantity of their semen with sperm banks where, for a fee,…
Africa’s oldest human DNA helps unveil an ancient population shift
Ancient Africans in search of mates traded long-distance travels for regional connections starting about 20,000 years ago, an analysis of ancient and modern DNA suggests. That shift occurred after treks…
Homo sapiens may have reached Europe 10,000 years earlier than previously thought
Stone Age Homo sapiens began migrating into Europe much longer ago than has typically been assumed. Discoveries at a rock-shelter in southern France put H. sapiens in Europe as early…
Homo sapiens bones in East Africa are at least 36,000 years older than once thought
Fossils from the oldest known Homo sapiens individual in East Africa are more ancient than previously thought. A partial H. sapiens skull and associated skeletal parts found in 1967 in…
‘Origin’ explores the controversial science of the first Americans
OriginJennifer RaffTwelve, $30 Scientific understanding of the peopling of the Americas is as unsettled as the Western Hemisphere once was. Skeletal remains, cultural artifacts such as stone tools and, increasingly,…
Clovis hunters’ reputation as mammoth killers takes a hit
An amateur archaeologist exploring a dried-out, ancient stream channel called Blackwater Draw near Clovis, New Mexico, made a startling discovery in 1929. He came across chiseled stone points strewn among…
