Why did the hominin cross the plain? We may never know. But anthropologists are pretty sure that a smattering of bare footprints preserved in volcanic ash in Laetoli, Tanzania bear witness to an evolutionary milestone. These small steps, taken roughly 3.5 million years ago, mark an early successful attempt by our common human ancestor to stand upright and stride on two feet, instead of four.
Nearly 50 years ago, Neil Armstrong also took a few small steps. On the moon. His bootprints, al ...read more
Supermassive black holes lurk in the hearts of every large galaxy. Some blast out jets that can spill into its host galaxy or even beyond. The energy carried by the jets is deposited in the surrounding material, playing a crucial role in the evolution of the galaxy and, in extreme cases, other galaxies nearby. And thanks to recent observations of the famous galaxy Cygnus A with the Chandra X-ray Observatory, astronomers have gotten a closer glimpse at just how those jets work — and ho ...read more
Tears often leave our faces feeling (and tasting) salty, but a closer look reveals the intricate patterns they can leave behind.
Norm Barker, director of pathology photography at Johns Hopkins University School of Medicine, focused his microscope on a human teardrop, using a lighting technique to enhance contrast. Barker saw that as it started to dry, the salt and other substances in the teardrop bunched together and crystalized in these intricate, snowflakelike shapes.
The picture ran ...read more
As technology advances, so do our fears about it. Socrates himself didn’t care for the new advancement of writing. And my parents were always on me to watch less TV.
Yet now as a parent, I’m always trying to limit how much screentime my 3-year-old spends with a phone or tablet. After all, everyone knows little kids are drawn to those portable devices like moths to a touch-sensitive flame, right?
Not so fast, suggests a study this week in JAMA Pediatrics. De ...read more
The town of Kabwe sits about 70 miles north of Zambia’s capital, Lusaka, as the crow flies. Just over 200,000 people live in this major transportation crossroads. Like most of this south-central African nation, Kabwe is perched on a high and vast plateau, a land of red soils dotted with shrubby legumes and canopies of small, spindly miombo trees.
Kabwe’s story is defined in part by a mine that opened in the early 1900s after rich deposits of lead and zinc were discovered on the edge ...read more
Author Vishay SinghPosted on Categories Discover Magazine