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Change of pace day. No Washington horrors.
Current Cicada concepts from Scientific American
All the hoopla over the 17-year cicadas, set to emerge any day now in the Northeast, has so far missed one of the greatest facts about them. Sure, it’s no surprise for grand gatherings of male animals to get together and sing their hearts out. Frogs do it, crickets do it, and we all know that humans do it. In animals it’s called a lek, in humans it’s called a rock band, and these words basically mean the same thing.
That’s what we thought 17-year cicadas were up to—they emerge only in these rare prime-numbered years after slowly growing underground to live just a few weeks high in the trees to sing, fly, mate and die. The females are just attracted to all this noise and mating then happens.
That’s as much of the story as we knew until seventeen years ago, when John Cooley and David Marshall discovered that in fact these remarkable insects have a three-part complex mating ritual, where the males begin with the distinctive “phaaaaarooooah” sound, but don’t stop there. They are only encouraged to move on when the females make a tiny flick of their wings, which leads them on to a second sound, “phaaaroah phaaaroah phaaaroah” and then after a second wing flick, the males move on to a third sound, “te te te te te te te te te” and only after all three sounds does he climb aboard and mating begins.
Two hundred years studying periodical cicadas and no one had ever noticed this until these two young scientists figured it out seventeen years ago and wrote their dissertations revealing a mating ritual far more complicated than that engaged in by any other insect. …
Free Republic tells us the story of one of China’s environmental disasters.
Back in the 1950s, China was going through its Great Leap Forward, an effort to transform China from a largely agrarian nation to a thriving industrial Marxist powerhouse. These sweeping (and often brutal) reforms, touched virtually every facet of Chinese life — and as one particular episode in China’s history points out, the animal kingdom was also far from immune. In 1958, China ordered the extermination of several pests, including sparrows — an ill-fated campaign that eventually led to catastrophe.
The Four Pests campaign
Chinese leader Mao Zedong initiated the Four Pests campaign after reaching the conclusion that several blights needed to be exterminated — namely mosquitoes, flies, rats, and sparrows. While many people nowadays would regard tampering with the ecosystem in such a radical way as a shockingly irresponsible idea, this was a classic case of something appearing like a good idea at the time. And according to environmental activist Dai Qing, “Mao knew nothing about animals. He didn’t want to discuss his plan or listen to experts. He just decided that the ‘four pests’ should be killed.”
Moreover, the idea fit in quite well with Mao’s hard-line totalitarian Communist ideology. Marx himself was far from an environmentalist, proclaiming that nature should be fully exploited by humans for production purposes (a legacy which may explain China’s poor environmental track record to this very day).
Now, while the Chinese citizens were called upon to wage war against all four of these pests, the government was particularly annoyed by the sparrow, or more specifically, the Eurasian Tree Sparrow. The Chinese were having a rough go of it as it was, adapting to collectivization and the re-invention of farming, so they felt particularly victimized by this bird which had a particular fondness for eating grain seeds. Chinese scientists had calculated that each sparrow consumed 4.5kg of grain each year — and that for every million sparrows killed, there would be food for 60,000 people. Armed with this information, Mao launched the Great Sparrow Campaign to address the problem. …
What-If posts on human being’s unique throwing abilities. The sport of baseball uses skills we needed so we could live and prosper as a species.
Humans are good at throwing things. In fact, we’re great at it; no other animal can throw stuff like we can.
It’s true that chimpanzees hurl feces (and, on rare occasions, stones), but they’re not nearly as accurate or precise as humans.[1][2] Antlions throw sand, but they don’t aim it. Archerfish hunt insects by throwing water droplets, but they use specialized mouths instead of arms. Horned lizards shoot jets of blood from their eyes for distances of up to five feet. I don’t know why they do this because whenever I reach the phrase “shoot jets of blood from their eyes” in an article I just stop there and stare at it until I need to lie down.
So while there are other animals that use projectiles, we’re just about the only animal that can grab a random object and reliably nail a target. In fact, we’re so good at it that some researchers have suggested rock-throwing played a central role in the evolution of the modern human brain.[3][4]
Throwing is hard. In order to deliver a baseball to a batter, a pitcher has to release the ball at exactly the right point in the throw. A timing error of half a millisecond in either direction is enough to cause the ball to miss the strike zone.[5]
To put that in perspective, it takes about five milliseconds for the fastest nerve impulse to travel the length of the arm.[6] That means that when your arm is still rotating toward the correct position, the signal to release the ball is already at your wrist. In terms of timing, this is like a drummer dropping a drumstick from the 10th story and hitting a drum on the ground on the correct beat. …
Next time you think you need a healthy snack, go to the freezer and get some ice cream. Seriously! Dig this from Nature Magazine.
Late in the morning on 20 February, more than 200 people packed an auditorium at the Harvard School of Public Health in Boston, Massachusetts. The purpose of the event, according to its organizers, was to explain why a new study about weight and death was absolutely wrong.
The report, a meta-analysis of 97 studies including 2.88 million people, had been released on 2 January in the Journal of the American Medical Association (JAMA)1. A team led by Katherine Flegal, an epidemiologist at the National Center for Health Statistics in Hyattsville, Maryland, reported that people deemed ‘overweight’ by international standards were 6% less likely to die than were those of ‘normal’ weight over the same time period.
The result seemed to counter decades of advice to avoid even modest weight gain, provoking coverage in most major news outlets — and a hostile backlash from some public-health experts. “This study is really a pile of rubbish, and no one should waste their time reading it,” said Walter Willett, a leading nutrition and epidemiology researcher at the Harvard school, in a radio interview. Willett later organized the Harvard symposium — where speakers lined up to critique Flegal’s study — to counteract that coverage and highlight what he and his colleagues saw as problems with the paper. “The Flegal paper was so flawed, so misleading and so confusing to so many people, we thought it really would be important to dig down more deeply,” Willett says.
But many researchers accept Flegal’s results and see them as just the latest report illustrating what is known as the obesity paradox. Being overweight increases a person’s risk of diabetes, heart disease, cancer and many other chronic illnesses. But these studies suggest that for some people — particularly those who are middle-aged or older, or already sick — a bit of extra weight is not particularly harmful, and may even be helpful. (Being so overweight as to be classed obese, however, is almost always associated with poor health outcomes.) …
And we have some beautiful pictures from Earth Science Picture of the Day.