Since Darwin revealed his seminal theory of evolution by natural selection, human beings have endeavored to understand their own evolutionary origins and history. A lot of questions still remain, but these mainly pertain to the specifics. Today, paleoanthropologists understand in great detail the evolutionary emergence of a number of traits that we consider, at least superficially, unique to modern humans.Human beings and chimpanzees, our closest living genetic relatives, are thought to share a ...read more
On Sept. 1, 1859, the brunt of a solar storm collided with Earth, disabling much of the world’s telegraph system. Sparks reportedly flew from telegraph machines, and the night sky turned an apocalyptic red, causing birds to chirp at what they thought was dawn.Today, scientists believe that in 1859, Earth collided with a massive number of electrically charged particles shot from the sun, all part of a coronal mass ejection. The episode became known as the Carrington Event, after the amateur ast ...read more
Earth is a complicated planet, with a huge number of complex processes working together to make the place livable for humans and every other organism. Since the industrial revolution began — and perhaps earlier — humans have been changing many of these components directly by removing resources like stored carbon or fresh water from the system or indirectly by releasing wasteful byproducts such as aerosols, carbon dioxide and other kinds of pollution.Earth scientists have broken down the majo ...read more
Colloquially known as the "sunshine vitamin," our bodies make vitamin D when our skin is exposed to sunlight — a built-in production system that hints at just how essential vitamin D is for our health.However, modern lifestyles that keep us indoors don't lend themselves to getting enough sun for sufficient vitamin D production. As a result, experts estimate that nearly a quarter of Americans aren't getting enough vitamin D.Despite its significance, questions remain: How much is enough? Can s ...read more
Pity the poor pumpkin: Since its domestication by early farmers around 10,000 years ago, few cultivars have been more burdened by myth and misinformation than this unassuming winter squash. But pumpkins are good for much more than warding away evil spirits (when carved) or acting as a delivery system for nutmeg, cinnamon, ginger and cloves (when pureed for pie).As it happens, pumpkins are nutritional powerhouses, pharmacological wonders and offer tasty treats for both humans and their pets. Here ...read more