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Chinese women at least 75 years of agedipped in the week before the HarvestMoon Festival and rose in the week after.

Smith’s data analysis reveals no sign ofdeath postponement before the HarvestMoon Festival for Chinese-, Korean-, andVietnamese-Americans. This result held,regardless of whether he defined elderly asbeing a minimum of 65 years old or 75 yearsold. It also made no difference whetherdeaths on the day of the festival were clas-sified as occurring before or after the event.

Moreover, Smith found that the originaldata from 1960 to 1984 exhibit a death-postponement pattern only if deaths on thefestival day are classified as having occurredafter the festival. That statistical partitionmakes no sense, he argues, because the fes-tival’s central ritual—a family meal—takesplace at midnight at the end of the holiday.

Other prior investigations of this allegeddelayed-death effect are also suspect, con-tend Judith A. Skala and Kenneth E.Freedland, both of Washington UniversitySchool of Medicine in St. Louis. Theyreviewed 18 such studies publishedbetween 1973 and 2001.

For example, a 1987 report found a 20 per-cent rise in deaths shortly after Christmas inOhio but no corresponding decline in deathsbefore Christmas. Reanalysis of the data indi-cated that the surge in deaths actually began5 days before the holiday and peaked onChristmas Day, the researchers say.

“Research . . . has failed to provide con-vincing evidence that psychological phe-nomena such as ‘giving up’ or ‘holding on’can influence the timing of death,” Skalaand Freedland conclude.

Smith’s findings and those of Skala andFreeland appear in the May/June Psycho-somatic Medicine.

In a commentary published with the newreports, Ellen L. Idler and Stanislav Kasl,both of Rutgers University in NewBrunswick, N.J., argue that there is still rea-son to suspect that deaths occur less fre-quently before major religious holidays thanafter them. In a 1992 study of elderly resi-dents of New Haven, Conn., Idler and Kaslreported a death-postponement pattern forobservant Jews around Yom Kippur andPassover and for observant Christiansaround Christmas and Easter. —B. BOWER

Geyser BashingDistant quake alterstiming of eruptions

A powerful earthquake that struck centralAlaska on Nov. 3, 2002, did more than justshake up the locals: It changed the eruptionschedule of some geysers in Wyoming’s Yel-lowstone National Park, more than 3,100kilometers away.

Yellowstone, one of the most activehydrothermal regions on Earth, containsmore than 10,000 geysers, hot springs,and steaming volcanic vents. As seismicwaves from the Alaskan quake rolledthrough the park, several small, normallycalm hot springs suddenly surged into aheavy boil, with some eruptions reachingheights of 1 meter or more, says Robert B.Smith of the University of Utah in SaltLake City. Another hot spring nearby,which normally discharges clear water,suddenly turned muddy.

Scientists and park rangers also notedbig changes in the eruption frequencies of8 of the 22 Yellowstone geysers that are con-stantly monitored with instruments. For afew weeks after the quake, Daisy Geyserblew its top more often than normal. LonePine Geyser, on the other hand, eruptedless frequently during the same period. Theresearchers suggest that seismic vibrationsmay have shaken loose some of the mineraldeposits that normally constrict the gey-sers’ subterranean plumbing, therebychanging their flow rates.

In contrast, Old Faithful, possibly theworld’s most renowned geyser, wasn’taffected by the remote temblor. Smith andhis colleagues report their findings in theJune Geology.

In the past, large quakes near Yellow-stone have influenced the eruption fre-quencies of some of the park’s geysers. The

influence of the Alaskan quake on Yellow-stone’s geysers is “the most distant trigger-ing [of changes in hydrothermal activity]that I’m aware of,” says Robert L. Chris-tiansen of the U.S. Geological Survey inMenlo Park, Calif.

In the first 6 hours after seismic wavesfrom the magnitude-7.9 Alaskan temblorpassed through Yellowstone, clusters ofquakes of magnitude 2 or smaller occurredaround several of the park’s majorhydrothermal systems. Although Yellow-stone has experienced clusters of quakesbefore, the November 2002 tremors markthe first time that multiple clusters havebeen observed there simultaneously.

In just 1 week, more than 1,000 quakeshit the park. It’s not clear whether the localtremors triggered the changes in hydrother-mal activity or vice versa, says Smith.

The study by Smith’s group suggests thateven small seismic triggers can have signif-icant effects, Christiansen notes. —S. PERKINS

Gender Neutral Men, women face samecancer risk from smoking

Over the past decade, the scientific com-munity has turned up conflicting evidenceregarding whether cigarettes impart agreater risk of lung cancer to women thanto men. In the largest comparison to date,researchers now report that the sexes sharea roughly equal risk of developing the can-cer from smoking.

The scientists also analyzed data from sixother studies and arrived at the same con-clusion. The findings appear in the June 2Journal of the National Cancer Institute.

“This paper does a good job of puttingthe debate to rest,” says Thomas V. Perneger,a physician at the University of Geneva inSwitzerland, who didn’t participate in thestudy.

Several studies in the 1990s had suggestedthat women who smoked fared worse thanmale smokers. However, those studies doc-umented smoking behavior on the basis ofpeople’s recollections, says Diane Feskanich,an epidemiologist at Harvard MedicalSchool and Brigham and Women’s Hospi-tal in Boston. She also notes that some stud-ies failed to compare women and men head-to-head and instead examined differences inlung cancer rates between smokers and non-smokers within each gender.

Feskanich and her colleagues used datafrom two massive studies—one of femalenurses and one of men in various healthprofessions—in which the participantscontributed updates on their health andlifestyle practices every 2 years. Theresearchers analyzed the data reportedbetween 1986 and 2000, comparing

THAR SHE BLOWS! Yellowstone’s CastleGeyser erupted less frequently after seismicwaves from a large quake in Alaska rippledthrough the park in November 2002.

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smoking behavior and the incidence oflung cancer for each group. The analysisaccounted for differences between the menand women such as body weight, height,age, cigarettes smoked per day, age at thestart of smoking, and time since formersmokers had quit.

The results indicate that women smok-ers are 10 percent more likely to developlung cancer, but this difference is smallenough that it could be due to chance, saysFeskanich. Moreover, even if the women’sexcess rate of contracting cancer has a validbiological basis, she says, the gender dif-ference pales in comparison to the dangerimparted by smoking itself, which boostsanybody’s risk of lung cancer by 10- to 20-fold over that of a nonsmoker.

When the researchers pored over sixother studies that had tracked people’ssmoking behaviors, the team found noexcess risk of lung cancer or death due tolung cancer in women.

“Gender is a bit of a hot topic, but it is notnecessarily relevant for all health problems,”Perneger says. Even so, gender might berelevant in designing smoking-preventionprograms, just as it has been in marketingcigarettes, he says. —N. SEPPA

Turtle TrekkersAtlantic leatherbacksscatter widely

Satellite surveillance of leatherback turtlesin the Atlantic Ocean is posing tricky newquestions for conservationists.

The data, the first of their kind to be pub-lished, reveal that these highly endangeredturtles range widely over the Atlanticinstead of sticking to “turtle corridors,” saysJean-Yves Georges of the National Centerfor Scientific Research in Strasbourg,France. That’s disappointing for conserva-tionists, he says, because satellite monitor-ing of Pacific turtles in the 1990s revealeda well-defined migration corridor thathelped focus conservation efforts. There’s nosuch luck in the Atlantic, Georges and hiscolleagues report in the June 3 Nature.

Another turtle-tracking paper in thesame issue of Nature highlights a secondcomplication. The leatherbacks dive mostlyto the depths targeted by long fishing linesthat hook commercially prized fish such astuna, report Graeme Hays of the Univer-sity of Wales in Swansea and his colleagues.

Leatherbacks are the biggest of themarine turtles, sometimes growing to alength of 6 feet. When a leatherback egghatches on a beach, the little turtle worksits way to the surf and paddles out to sea.What happens next has remained mostlyunknown. Mating apparently takes place atsea, since scientists see only female adults onland, when they make forays onto beachesto lay eggs, says Georges. No one knows howlong the turtles live, but speculation runs ashigh as 80 to 100 years.

The species as a whole isdeclining, says Georges. In1982, rough estimates ofnesting females worldwidereached 115,000. By 1995, thenumber had dropped to34,500. The Atlantic popula-tion is the biggest remainingone and therefore representsthe best hope for sustainingthe species, he says.

Georges, Sandra Ferraroli,and their colleagues fittedsmall backpack transmittersonto 31 female Atlantic leatherbacks onbeaches of French Guiana and Suriname.The team then followed the animals’ move-ments for up to 16 months. The turtlesfanned out to the north and to the east, andseveral looped around the mid-Atlantic.

The same travel pattern showed up inthe paths of the nine turtles that Hays andhis colleagues tracked to study diving depth.

The difference between Atlantic- andPacific-movement patterns in turtlesprobably stems from the differences inthe food-rich zones where warm and coldcurrents clash, comments Frank Paladinoof Indiana Purdue University at FortWayne. He welcomes the new studies as“important” for biologists trying to workout ways to keep commercial fisheriesfrom inadvertently killing endangeredsea turtles. —S. MILIUS

Got Milk?Dairy protein providesbone-forming boost

Calcium isn’t the only thing in milk that’sgood for bones, a new study suggests. A pro-tein present in cow’s milk, as well as inhuman breast milk, stimulates bone-form-ing cells in lab dishes and induces bonegrowth when injected into mice, research-ers have found.

The molecule, an iron-binding proteincalled lactoferrin, could form the basis of anew treatment for osteoporosis, says studyleader Jillian Cornish of the University ofAuckland in New Zealand.

When asked by the New Zealand dairyindustry to search for novel substances in

milk that might influence bone growth,Cornish was initially skeptical about find-ing anything new in what she considered tobe such a thoroughly studied substance.

Her skepticism is gone. While calciumprovides raw material for bone growth,other, unknown substances in milk appearto directly stimulate the activity ofosteoblasts, the cells that form new bone.Cornish and her colleagues homed in onlactoferrin, which is typically found in body

fluids such as tears, saliva,semen, and milk, as well as inseveral tissues. Immune cellscalled neutrophils also releaseit during inflammation, whenthe protein’s antimicrobialproperties come in handy.

The New Zealand teamfound that lactoferrin stimu-lates the proliferation andmaturation of osteoblasts inlab dishes. It also protects thecells from apoptosis, a processthat leads to cell death, theinvestigators report in an

upcoming Endocrinology. Lactoferrineven inhibits the generation of osteoclasts,cells that counter osteoblasts by resorb-ing bone.

“We were absolutely stunned,” says Cor-nish. Lactoferrin “was never known to bebone-active.”

To test the protein’s effects on live ani-mals, the investigators injected it under thescalps of adult mice for 5 consecutive days.The treatment significantly accelerated therate of new skull-bone formation. “It’s a verypotent molecule,” says Cornish.

In mammals, lactoferrin production risesin an embryo during the last half of gesta-tion, an indication that it promotes skele-tal development. Its high concentrations inmilk, particularly in colostrum, the richmilk produced immediately after a baby isborn, suggest that it might also be impor-tant to newborns, says Cornish.

In another report to appear in a forth-coming Molecular Endocrinology, Cornishand her colleagues present evidence thatlactoferrin affects osteoblasts by binding tocell-surface proteins called low-densitylipoprotein receptors.

Although there are drugs that preventbone resorption by osteoclasts, only oneFood and Drug Administration–approvedcompound, parathyroid hormone, stimu-lates bone formation. Cornish and her col-leagues may have unearthed a new bone-growing pathway, say other researchers.

“It’s very exciting. It opens up a wholenew area,” says osteoporosis researcherClifford J. Rosen of St. Joseph Hospital inBangor, Maine. For lactoferrin to serve asan osteoporosis drug, investigators needto show that it can reach bone throughoutthe body, rather than just where it’sinjected, he cautions. —J. TRAVIS

SCIENCENEWSThis Week

70%Worldwidedecline innesting femaleleatherbackturtles, 1982to 1995

STATS

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