The "challenge hypothesis" first put forth in 1990 in an article in The American Naturalist states that, as an evolutionary holdover from the need to guard mates and progeny, testosterone levels in males are high after vicious competition. Evidence to support the hypothesis has been found in birds. And in human competitors following various types of sporting competitions, elevated testosterone levels have been found--but only in winners. Even politics can provide a testosterone boost, and not only to the direct competitors. For example, right after the 2008 elections, researchers found higher testosterone levels in men who voted for Barack Obama than in men who voted for John McCain.
Now, demonstrating perhaps that the exquisitely sensitive thumb Google has on the pulse of our nation can serve as an epidemiological assay of biomarkers, researchers from Villanova and Rutgers Universities have been following the search terms used in red and blue states. They report that people in traditionally Republican states conducted Google searches for pornography keywords more often after the 2010 midterm elections (widely seen as a Republic victory) than after the 2008 elections (widely seen as a Democratic victory). On the other hand, people from Democratic states searched for pornography terms less frequently after the 2010 Democratic loss than after the 2006 Democratic win. The study assumes a direct correlation between testosterone levels and interest in pornography. It is "Pornography Seeking Behaviors Following Midterm Political Elections in the United States: A Replication of the Challenge Hypothesis," in the May 2011 issue of Computers in Human Behavior.
Wednesday, May 11, 2011
Monday, May 02, 2011
In Scientific American This Month: Coral in Love
In May's Scientific American:
It is hard to court the opposite sex when you are cemented in place, which explains why polyps—the tiny creatures whose exoskeletons form corals—do not reproduce by mating. Instead they cast millions of sperm and eggs into the sea, where they drift up to the ocean surface, collide, form larvae and float away to form new coral reefs....
Read article.
It is hard to court the opposite sex when you are cemented in place, which explains why polyps—the tiny creatures whose exoskeletons form corals—do not reproduce by mating. Instead they cast millions of sperm and eggs into the sea, where they drift up to the ocean surface, collide, form larvae and float away to form new coral reefs....
Read article.
In Discover Magazine This Month: 20 Things You Didn't Know about Cyrstals
In May's Discover Magazine:
1 It’s all about the rhythm: Crystals are repeating, three-dimensional arrangements of atoms, ions, or molecules.
2 Almost any solid material can crystallize—even DNA. Chemists from New York University, Purdue University, and the Argonne National Laboratory recently created DNA crystals large enough to see with the naked eye. The work could have applications in nanoelectronics and drug development.
3 One thing that is not a crystal: leaded “crystal” glass, like the vases that so many newlyweds dread. (Glass consists of atoms or molecules all in a jumble, not in the well-patterned order that defines a crystal.)
See "things" 4-20.
1 It’s all about the rhythm: Crystals are repeating, three-dimensional arrangements of atoms, ions, or molecules.
2 Almost any solid material can crystallize—even DNA. Chemists from New York University, Purdue University, and the Argonne National Laboratory recently created DNA crystals large enough to see with the naked eye. The work could have applications in nanoelectronics and drug development.
3 One thing that is not a crystal: leaded “crystal” glass, like the vases that so many newlyweds dread. (Glass consists of atoms or molecules all in a jumble, not in the well-patterned order that defines a crystal.)
See "things" 4-20.
Wednesday, April 20, 2011
Women Think Venus Is Funny; Men Prefer Mars
Gender Differences in How We Process Humor
Functional MRI images have shown gender differences in emotion processing, and behavioral studies have found gender differences in humor processing. In "Gender Differences in the Neural Correlates of Humor Processing: Implications for Different Processing Modes" (in the April issue of Neuropsychologia) an international team of investigators report on an experiment assessing the reactions of 14 females and 15 males to cartoons. Blood oxygenation levels were assessed alongside fMRIs. Women, it seems, process humor primarily in the part of the cortical processing system associated with primitive emotions and motivations. While men, too, engage those deep brain structures, more than women they also engage parts of the cortex associated with evaluative thinking.
Functional MRI images have shown gender differences in emotion processing, and behavioral studies have found gender differences in humor processing. In "Gender Differences in the Neural Correlates of Humor Processing: Implications for Different Processing Modes" (in the April issue of Neuropsychologia) an international team of investigators report on an experiment assessing the reactions of 14 females and 15 males to cartoons. Blood oxygenation levels were assessed alongside fMRIs. Women, it seems, process humor primarily in the part of the cortical processing system associated with primitive emotions and motivations. While men, too, engage those deep brain structures, more than women they also engage parts of the cortex associated with evaluative thinking.
Tuesday, April 05, 2011
Which Came First, the Tool or the Hand Size?
Did Technology Drive Human Evolution?
140 years ago Charles Darwin speculated that tool use may have influenced the evolution of the human hand. Now, in "Technology Based Evolution? A Biometric Test of the Effects of Handsize Versus Tool Form on Efficiency in an Experimental Cutting Task," in-press at the Journal of Archeological Science, two anthropologists at the University of Kent in Canterbury are investigating the particulars of that idea. Through a series of experiments with stone flake tools (similar to the those used by African hominids 2.6 million years ago) and un-handled steel blades, they have shown that bigger hands use those tools more efficiently. The scientists speculate that just as opposable thumbs may have enabled tool use, tool use may have influenced the biological evolution of hand size—and of musculature and bone structure in the hand. As eons ticked on, it was the hominids with genes coding for hands adept at tool use that survived.
140 years ago Charles Darwin speculated that tool use may have influenced the evolution of the human hand. Now, in "Technology Based Evolution? A Biometric Test of the Effects of Handsize Versus Tool Form on Efficiency in an Experimental Cutting Task," in-press at the Journal of Archeological Science, two anthropologists at the University of Kent in Canterbury are investigating the particulars of that idea. Through a series of experiments with stone flake tools (similar to the those used by African hominids 2.6 million years ago) and un-handled steel blades, they have shown that bigger hands use those tools more efficiently. The scientists speculate that just as opposable thumbs may have enabled tool use, tool use may have influenced the biological evolution of hand size—and of musculature and bone structure in the hand. As eons ticked on, it was the hominids with genes coding for hands adept at tool use that survived.
Saturday, April 02, 2011
In Scientific American This Month: Outsmarting Dengue Fever
In April's Scientific American
Just after sunrise in early January, a delivery van trundled along a suburban street in Queensland, Australia. Inside were tubs filled with a type of mosquito that carries dengue fever, the flu-like illness that annually sickens 50 million to 100 million people worldwide. Workers inside the van stopped at every fourth house, took out what resembled a small Chinese food container and released 40 mosquitoes into the wild. After a week, they had filled the air with 6,000 insects. By early March they had launched 72,000....
Read the article.
Just after sunrise in early January, a delivery van trundled along a suburban street in Queensland, Australia. Inside were tubs filled with a type of mosquito that carries dengue fever, the flu-like illness that annually sickens 50 million to 100 million people worldwide. Workers inside the van stopped at every fourth house, took out what resembled a small Chinese food container and released 40 mosquitoes into the wild. After a week, they had filled the air with 6,000 insects. By early March they had launched 72,000....
Read the article.
Thursday, March 03, 2011
Shaky Reasoning
In 2008, the Vermont Yankee nuclear power plant in Vernon, Vermont began storing high-level radioactive waste in 19-foot tall dry casks outdoors, on a concrete slab 254 feet away from the bank of the Connecticut River.
That's a foot and a half beyond what Dr. Leslie Kanat, a Geology Professor at Johnston State College, calls the "Probable Maximum Flood Level."
I am more than a bit concerned about those casks, but maybe I ought to feel relieved--even if a foot and a half doesn't sound like much. Maybe I also ought to feel relieved that Holtec International, the company supplying the casks, reports that their casks stay operational even when submerged at 50 feet for 8 hours. But while Holtec's tests have reassured me that river water would not be a problem for those dry casks, I'm not so sure about river mud.
Holtec's dry casks have vent holes at top and bottom. They are designed for air to enter at bottom, cool the waste, and exit at top.
What would happen if those vents were blocked? Did Holtec run tests for that?
It did not. But in 2002, Dr. Marvin Resnikoff, an international consultant on radioactive waste management, was asked by The Connecticut Yankee Decommissioning Advisory Committee how long it would take for a cask to overheat if vents were blocked. His answer: Maybe a week.
"Maybe." And, again, maybe I should feel relieved. After, all, there's a nice margin of safety in that hypothetical week. I can imagine fire engines arriving at the high-level radioactive waste storage slab right after helping little old ladies out of their collapsed homes, and taking care to hose down the casks after hosing down the fires decimating Main Street. But what about the fact that guesses are sometimes off the mark? What if there were not a week to spare but only two days or three? Would emergency workers even know to abandon their attempts to help survivors and begin to frantically deal with muddy dry casks?
And what about the fact that, during his testimony to the Connecticut Yankee Decommissioning Advisory Committee, Dr. Resnikoff explained that each dry cask contains a Cesium and Strontium inventory equal to 10 Hiroshima bombs?
Entergy, the plant's corporate owner, has never actually acknowledged that mud could reach the vents of the dry casks at Vermont Yankee. Their directors and administrators keep the conversation focused solely on water. But Ray Shadis, technical director for the anti-nuclear watchdog group New England Coalition, is concerned about the combination of Cesium, Strontium, and high temperatures due to a failed, mud-dependent cooling system. In a not-too-difficult-to-imagine scenario, Shadis suggests that the ground surrounding the concrete slab that holds the casks could become wet with river water. Consequently (he says), the slab could become unstable.
And then what?
Well, if you shake even relatively dry soil really, really hard, its strength and stiffness are reduced. That's called "liquefaction." It's responsible for much of the damage during earthquakes. If you actually add liquid to the mix, you create something like quicksand.
What if the Connecticut River Valley suffered a double whammy of flood plus even a minor earthquake? Could the ground around the slab holding the dry casks become like quicksand? Could an edge of the slab shift or, worse, tip?
Even Entergy has suggested that the ground around the concrete slab could get an occasional and maybe even regular soaking soaking from river water. What they haven't gone out of their way to point out is that Vermont is in a bit of an earthquake zone. We have been significantly rattled 15 times since 1900.
Most scientists agree that we are entering an unstable time weather-wise, with melting ice caps, rising waters, and the possibility of more frequent flooding. Given that, I can't help but question Entergy's foresight in trying to get a license extension allowing them to create another 20 years of radioactive waste, only to store it in an earthquake zone near a population center at river's edge.
This is adapted from a Vermont Public Radio commentary by the author.
That's a foot and a half beyond what Dr. Leslie Kanat, a Geology Professor at Johnston State College, calls the "Probable Maximum Flood Level."
I am more than a bit concerned about those casks, but maybe I ought to feel relieved--even if a foot and a half doesn't sound like much. Maybe I also ought to feel relieved that Holtec International, the company supplying the casks, reports that their casks stay operational even when submerged at 50 feet for 8 hours. But while Holtec's tests have reassured me that river water would not be a problem for those dry casks, I'm not so sure about river mud.
Holtec's dry casks have vent holes at top and bottom. They are designed for air to enter at bottom, cool the waste, and exit at top.
What would happen if those vents were blocked? Did Holtec run tests for that?
It did not. But in 2002, Dr. Marvin Resnikoff, an international consultant on radioactive waste management, was asked by The Connecticut Yankee Decommissioning Advisory Committee how long it would take for a cask to overheat if vents were blocked. His answer: Maybe a week.
"Maybe." And, again, maybe I should feel relieved. After, all, there's a nice margin of safety in that hypothetical week. I can imagine fire engines arriving at the high-level radioactive waste storage slab right after helping little old ladies out of their collapsed homes, and taking care to hose down the casks after hosing down the fires decimating Main Street. But what about the fact that guesses are sometimes off the mark? What if there were not a week to spare but only two days or three? Would emergency workers even know to abandon their attempts to help survivors and begin to frantically deal with muddy dry casks?
And what about the fact that, during his testimony to the Connecticut Yankee Decommissioning Advisory Committee, Dr. Resnikoff explained that each dry cask contains a Cesium and Strontium inventory equal to 10 Hiroshima bombs?
Entergy, the plant's corporate owner, has never actually acknowledged that mud could reach the vents of the dry casks at Vermont Yankee. Their directors and administrators keep the conversation focused solely on water. But Ray Shadis, technical director for the anti-nuclear watchdog group New England Coalition, is concerned about the combination of Cesium, Strontium, and high temperatures due to a failed, mud-dependent cooling system. In a not-too-difficult-to-imagine scenario, Shadis suggests that the ground surrounding the concrete slab that holds the casks could become wet with river water. Consequently (he says), the slab could become unstable.
And then what?
Well, if you shake even relatively dry soil really, really hard, its strength and stiffness are reduced. That's called "liquefaction." It's responsible for much of the damage during earthquakes. If you actually add liquid to the mix, you create something like quicksand.
What if the Connecticut River Valley suffered a double whammy of flood plus even a minor earthquake? Could the ground around the slab holding the dry casks become like quicksand? Could an edge of the slab shift or, worse, tip?
Even Entergy has suggested that the ground around the concrete slab could get an occasional and maybe even regular soaking soaking from river water. What they haven't gone out of their way to point out is that Vermont is in a bit of an earthquake zone. We have been significantly rattled 15 times since 1900.
Most scientists agree that we are entering an unstable time weather-wise, with melting ice caps, rising waters, and the possibility of more frequent flooding. Given that, I can't help but question Entergy's foresight in trying to get a license extension allowing them to create another 20 years of radioactive waste, only to store it in an earthquake zone near a population center at river's edge.
This is adapted from a Vermont Public Radio commentary by the author.
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