agnieszka biskup — writer & editor

The Voyager 1 space probe, launched in 1977, is now more than 8 billion miles from Earth, but whether it has actually left the outer limits of the solar system is still a matter of debate. In the Nov. 6 Nature, researchers led by Stamatios Krimigis of Johns Hopkins University report that the craft already has passed that historic milestone, entering the boundary marking the edge of the sun’s influence, known as the termination shock.  The termination shock arises from supersonic particles streaming from the sun (the solar wind) violently intersecting with particles from deep space. Krimigis and his team offer a drop in solar wind speed, among other data, as proof that Voyager journeyed through that barrier. Continue reading →

Roosters have a “sperm budget” and can be picky in allocating their limited resources, Tommaso Pizzari and his colleagues at the University of Leeds report in the Nov. 6 Nature. They have discovered that roosters give more sperm to a new mate than to a familiar one, more to females with larger combs, and more when rival males are present. Continue reading →

It appears that “Supermom” has a basis in fact. According to a study published in Physiology and Behavior, neuroscientist Craig Kinsley of the University of Richmond has found that motherhood makes females calmer when provoked and more courageous. Kinsley said he believes that the hormonal changes that occur during pregnancy may somehow change the brain to deal with the stresses of being a mother. Studying rats, Kinsley discovered that females who had had at least one litter of pups were less likely than “virgin” females to get upset when provoked. The rat moms were also more likely to explore new environments. Kinsley stressed out his rats by putting them in bright, open rooms with no places to hide and then measured the amount of a brain chemical linked with fear and stress. The rat moms had lower levels of the chemical and also showed less activity in their amygdalas, the fear center of the brain. And while the females who had never had a litter would freeze up in the unfamiliar environment, the rat moms would go exploring. Kinsley told Reuters: “There’s something about pregnancy and subsequent exposure to offspring that create a more-adaptive brain, one that’s generally less susceptible to fear and stress.”

This news brief appeared in the Random Data column of the Boston Globe’s Health/Science section on 11/04/2003.

Pterosaurs, the now-extinct flying reptiles that once dominated the skies (and bad caveman movies), may have been accomplished and agile aerial predators, report researchers in the Oct. 30 Nature. Lawrence Witmer of the University of Ohio and his colleagues ran pterosaur skulls through a high-resolution scanner to obtain digital 3-D reconstructions of the creatures’ brains. Overall, they found them rather birdlike, but the pterosaurs had much larger floccular lobes, a part of the brain that controls movement. (The floccular lobes took up 7.5 percent of a pterosaur’s total brain mass, compared to less than 2 percent in birds.) The researchers propose that the lobes were so big so they could gather information from the pterosaurs’ vast and sensitive wing membranes, helping them build up a detailed map of the forces the wings detected. “Equipped with their `smart’ wings, pterosaurs would have excellent flight control. Despite their antiquity, they could even have outperformed modern birds and bats,” wrote David Unwin of Berlin’s Humboldt University, in an accompanying commentary.

This news brief appeared in the Random Data column of the Boston Globe’s Health/Science section on 11/04/2003.

Female wolf spiders, being of a practical nature, commonly eat their suitors. Eileen Hebets, a Cornell University researcher, has some advice for the males who’d like to better their chances of surviving a tryst: Perhaps an introduction might be in order. It appears that female spiders can recognize one male spider from another and familiar-looking spiders have a better chance of not being cannibalized. Males of most other spider species appear alike, but each male wolf spider has its own special look: Some have ornamental tufts of hair on their legs and their exoskeletons come in different colors. As Hebets reported in the Proceedings of the National Academy of the Sciences last week, she introduced 81 sexually immature females to a variety of sexually mature males. She discovered that once the females were ready to mate, they consistently chose males that looked like the males they had been introduced to earlier. The females also were found to be more likely to devour spiders that looked completely unfamiliar to them. Stated Hebets: “This shows that invertebrates have social recognition.” Surprisingly enough, even for spiders, “social experience influences mate choice.”

This news brief appeared in the Random Data column of the Boston Globe’s Health/Science section on 11/04/2003.

Are you a health-conscious do-gooder worried about giving out sugary treats this Halloween that may rot children’s teeth and weigh them down with unnecessary calories? Forget the boxes of raisins (a lame treat anyway), and hand out nonedible toys instead, all without the worry of your house being egged in retaliation. According to a Yale study published in the Journal of Nutrition, Education and Behavior, children are just as likely to choose a toy as candy on Halloween. The study was conducted at seven homes in five Connecticut towns last Halloween and involved 284 children between the ages of 3 and 14. The kids were offered a choice between fruit-flavored candies, such as lollipops or chews, or toys, such as stretch pumpkin men or glow-in-the-dark insects. It was found that half of the children chose toys when offered both. “This finding may reassure adults that children will not be disappointed by noncandy treats,” said the study’s principal investigator, research scientist Marlene Schwartz of Yale’s Department of Psychology.

This news brief appeared in the Random Data column of the Boston Globe’s Health/Science section on 10/28/2003.

Joining the ranks of animals like humans and monkeys, walruses have been found to be mostly right-handed. The walrus prefers using its right flipper over its left one when foraging underwater for food buried in mud on the sea bed. A team of scuba-diving researchers from Denmark, Sweden, and Greenland filmed the animals digging for clams, a favorite food, and reported the discovery last week in the online journal, BMC Ecology. The videotapes revealed that the walruses had various other foraging methods, but using their flippers was the most-popular technique by far, being used 70 percent of the time. And when only flipper-use was considered, it was found that the right flipper was used 89 percent of the time. Anatomical studies of walrus skeletons in collections confirmed that the bones in their right limbs are longer than those in their left, an effect also seen in right-handed humans and that probably develops due to greater use of the right limb. “The implication of these findings,” the team stated, “suggest that tool use and object manipulation is not mandatory for the development of strong limb preferences or handedness.”

This news brief appeared in the Random Data column of the Boston Globe’s Health/Science section on 10/28/2003.

Do you think getting a head count of all the people living in the United States is hard? Try doing a census on everything that lives in the world’s oceans. The Census of Marine Life is a massive, billion-dollar, 10-year-long scientific collaboration involving more than 50 countries and hundreds of scientists that will attempt to identify and catalog life in the ocean. After three years of work, the first report was issued last week in Washington. More than 15,000 species of marine fish are now included in the census, but, according to the researchers, some 5,000 previously unknown ocean fish species are yet to be discovered. Currently 210,000 total species of marine life are known, but the scientists estimate that the actual number could be up to 10 times higher. More than identifying new species, the census is also tracking fish migration patterns, examining the degradation of coral reef ecosystems, and discovering areas that are aquatic-biodiversity hotspots. Despite its enormous importance to humans, much of the ocean remains unexplored and relatively little is known about its inhabitants. “This is the start of the first great voyage of discovery of the 21st century,” stated J. Frederick Grassle of Rutgers University, chairman of the Census Scientific Committee. “More importantly, it begins the first systematic global effort to measure our oceans’ vital signs, and guide what must be done to reverse their decline.”

This news brief appeared in the Random Data column of the Boston Globe’s Health/Science section on 10/28/2003.

Finally, what adulterous female songbirds have always wanted: Scientific proof of the evolutionary advantages of promiscuity. A team of researchers from the Max Planck Research Center for Ornithology in Germany and the Zoological Museum in Norway spent four years studying a population of songbirds known as blue tits breeding in the Viennese Forest in Austria. A female blue tit normally chooses a single social partner, a male to defend a territory and to help care for offspring, but she also occasionally mates with other males outside her breeding territory without her partner’s knowledge. The researchers report in the Oct. 16 Nature that they have found that the offspring from these extramarital affairs were more genetically varied than those sired by her social mate, and were more likely to survive and reproduce. Females from these extramarital couplings were found to produce larger clutches of eggs and lived longer. Males from these couplings also produced more surviving offspring. As an added bonus, these males also tended to have more elaborate head crests, assumed to make them more attractive to other females. The study supports the idea that females mate many times to get the best possible genes for their young and gives evidence that evolutionarily speaking — at least for female blue tits — promiscuity may be the way to go.

This news brief appeared in the Random Data column of the Boston Globe’s Health/Science section on 10/21/2003.

When you’re flying in a jumbo jet, do you ever think about how much of the plane’s holding capacity is devoted to carrying fuel? A team of researchers from NASA’s Marshall Space Flight Center in Huntsville, Ala., NASA’s Dryden Flight Research Center at Edwards, Calif., and the University of Alabama have thought about it quite a bit, and have come up with a way to eliminate aircraft from carrying fuel altogether. They have developed a model airplane that is powered and kept aloft by a laser beam delivered from the ground — no onboard fuel required. Tracking the aircraft in flight, the beam is directed to specially designed photovoltaic cells onboard, which power the plane’s propeller. Robert Burdine, Marshall’s laser project manager, said that “the craft could be kept flying as long as the energy source, in this case the laser beam, is uninterrupted.” So far, the technology has powered only a small, radio-controlled model airplane that was tested indoors, but hopes are high for its potential use in surveillance and telecommunications. “This is the first time that we know of that a plane has been powered only by the energy of laser light,” Burdine said. “It really is a ground-breaking development for aviation.”

This news brief appeared in the Random Data column of the Boston Globe’s Health/Science section on 10/21/2003.