STRANGE BUT TRUE
Q: Economic inequality has long been documented, but how long is that? When researchers examined 62 archeological sites dating from 10,000 to 250 years ago, what did they unearth? How did the Old World and New World differ?
A: Using house size as a proxy for wealth and a measure called the Gini coefficient, archaeologist Tim Kohler and his colleagues (Nature) found that inequality gradually increased as societies moved from hunting and gathering to farming. Gini coefficients range from zero, if wealth is uniformly distributed, to one, if all wealth is concentrated in a single person. About 2,500 years after the start of agriculture, both the Old World and New World had average Gini coefficients of 0.35. New World inequality didn’t change much after that, but that of the Old World climbed to about 0.6 by the time of the destruction of Pompeii in ancient Rome. Perhaps this was because the Old World had draft animals (oxen, horses) and the economic capital associated with owning these animals accrued from generation to generation.
Describing the work in Science magazine, reporter Lizzie Wade notes, “Those numbers are far below the wealth inequality seen today in the United States and China, which have Gini coefficients of 0.8 and 0.73, respectively.”
Q: If you asked a pack of wild dogs what they thought about democracy, you might get a surprising answer.
A: When deciding whether or not to move to a new location, a pack of African wild dogs will gather in a “social rally,” a high-energy greeting ceremony where individuals “vote” to move by emitting audible rapid nasal exhalations (“sneezing”). Writing in “Proceedings of the Royal Society B,” Brown University researcher Reena Walker and her colleagues report that more sneezes mean a higher probability that a pack will move. Wild dog packs have a strong dominance hierarchy, and rallies initiated by dominant individuals require only a few sneezes to elect relocation. But even without leader support, the rank-and-file can force relocation with enough sneezes. Conclude the authors, “We found that sneezes, a previously undocumented unvoiced sound in the species ..., may function as a voting mechanism to establish group consensus in an otherwise despotically driven social system.”
Q: What remarkable feat did scientists achieve by taking strontium atoms, putting them in grid-like patterns and then stacking them?
A: They created the most precise atomic clock ever, reports New Scientist magazine. With most atomic clocks, time is measured using microwaves emitted by the electrons around atoms of the isotope caesium-133, which jump between lower and higher orbits as they absorb and then lose energy from a laser. But the transition frequency of these electrons is limited to 9 billion times per second.
Enter University of Colorado’s Jun Ye and his team that used strontium atoms instead, whose electrons can transition nearly 1 million billion times per second. They put the atoms into a 3-D lattice structure, then cooled it to near absolute zero temperature, “which turned the atoms into what’s called a quantum gas. Instead of colliding, the particles ‘move like waves — they start to avoid each other,’” Ye says.
The result? A clock that would lose or gain only about one second in 90 billion years, more than six times the age of the universe!
Send questions to brothers Bill and Rich Sones at sbtcolumn@gmail.com.