Q: They risk death for you, fight crime and are tough as superheroes to boot. Who are these praiseworthy folks?
A: No, they're not police officers or firefighters but rather everyday garbage collectors, who face dangerous situations more often than you might imagine, reports Samuel Anderson in "Mental Floss" magazine. "With 33 fatalities per 100,000 employees a year, sanitation work is one of America's deadliest jobs — two to three times as dangerous as being a police officer and seven times as dangerous as firefighting." Also, in some areas they're "neighborhood watchpeople" who report suspicious activity to police.
As to their superhero status, back in the 1940s, sanitation workers in New York City were required "to lift a 120-pound trash can onto a tall ledge, climb an eight-foot fence, and run a football field with 50 pounds in each hand" (the so-called "Superman" test, which has since been relaxed).
Interested in joining their ranks? Not so fast! In 2014, out of 96,000 job applicants in New York City, only 500 were hired, for an acceptance rate of less than one percent, making the field "more cutthroat than Harvard's six percent."
Q: He was said to be "the merchant of death" — quite a powerful indictment. But did the pronouncement get it right?
A: Gunpowder goes back to ninth-century China but not until the mid-1800s were detonators developed and dynamite invented, reports "Time" magazine's special edition on "Great Scientists." The inventor was Swedish chemist, engineer and arms manufacturer Alfred Nobel (1833-1896) and his invention made him rich. But a year before he died, he redirected his fortune to establish the Nobel Prizes, perhaps after reading "his own obituary" in a French newspaper: "The merchant of death is dead. Dr. Alfred Nobel, who became rich by finding ways to kill more people faster than ever before, died yesterday." Actually it was Alfred's brother Ludvig who had died, but the mistake proved consequential to Nobel's place in history.
Q: This is not to say that mosquitoes are smarter than you, but as "Science News" magazine puts it, "Good luck outsmarting one of them." Why?
A: The ways mosquitoes have for sensing the presence of bitable bodies are "annoyingly robust," says the magazine's Susan Milius. As chemical ecologist Ben Webster noted in one study, the carbon dioxide (CO2) in exhaled breath betrays a living target, and "blood-hunting mosquitoes prove sensitive to the merest whiff of CO2," even as little as 0.015 percent above regular air.
Now a new report in "Current Biology" by Floris van Breugel of Caltech suggests that mosquitoes use other clues since CO2 plumes can get scattered. For example, researchers found that plastic filters and dark spots that contrasted with the flooring piqued the insects' interest. Added to visual contrasts was the lure of heat since warm objects didn't require the puff of CO2 as a trigger. Their conclusion: "The interactions of these clues mean that a mosquito catching an exhalation of CO2 can fumble along until some visually interesting or warm object invites closer scrutiny."
A final warning comes from the study's co-author, neuroscientist Michael Dickinson: Mosquitoes make mistakes, "but when they fly to a rock instead of a person, they pull back and try again. And again. 'It's the relentlessness that ensures success.'" Watch out!
Send STRANGE questions to brothers Bill and Rich at email@example.com