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magnitude 7.0 temblor originating in theCentral Apennines.

The greatest ground motions caused bythe simulated quakes appeared along theedges of the floodplain, where seismicwaves traveling through the sedimentbounced off the rocky edges of the rivervalley and reinforced each other.

Olsen notes that parts of central Romethat experienced large ground motionsduring the simulations were locations thathad been heavily damaged in actualquakes.

What surprised team members was thatthe virtual quake originating in the Cen-tral Apennines shook Rome for as long asa minute, he notes. Seismic vibrations inthe sediments under the city echoed backand forth through the basin, extending thequake’s duration. The researchers reporttheir results in the February Bulletin ofthe Seismological Society of America.

Simulations such as these could enablescientists to determine which of Rome’sancient buildings are most at risk of col-lapse during a major quake, says KirkMartini, a structural engineer at the Uni-versity of Virginia in Charlottesville.Preservationists could then focus theircostly and time-consuming efforts on seis-mically retrofitting the most vulnerablehistorical sites. —S. PERKINS

Big Womanwith a DistantPastStone Age gal embodieshumanity’s cold shifts

A 260,000-year-old partial skeleton exca-vated in northwestern China 22 years agorepresents our largest known female ances-tor, according to a new analysis of the indi-vidual’s extensive remains.

This ancient woman puts a moderntwist on Stone Age human evolution, sayKaren R. Rosenberg of the University ofDelaware in Newark, Lü Zuné of PekingUniversity in Beijing, and Chris B. Ruffof Johns Hopkins University School ofMedicine in Baltimore. The fossil indi-vidual’s large size and the apparent adap-tation of her body to cold conditions are“consistent with the idea that patterns ofhuman anatomical variation that we see

today have deep evolutionary roots,”Rosenberg asserts.

Although the woman belonged to theHomo genus, her species is uncertain.Now known as the Jinniushan specimen,she stood roughly 5 feet, 5-1⁄2 inches talland tipped the scales at 173 pounds, thethree anthropologists estimate. The onlyStone Age Homo woman known to haveapproached that size weighed an esti-mated 163 pounds. Her partial skeletoncame from a 100,000-year-old Neander-tal site in France.

The Jinniushan specimen’s size reflects

her membership in a population that, as anadaptation for retaining heat in a cold cli-mate, evolved large, broad bodies with shortlimbs, a shape similar to that of near-polarpopulations today, the scientists propose inan upcoming Proceedings of the NationalAcademy of Sciences.

The large estimated brain size of the Chi-nese fossil supports a current theory ofmid–Stone Age brain expansion in Homospecies, the researchers say. Earlier analy-ses of other fossils’ skulls and lower-bodybones—not including multiple bones fromsingle individuals—had indicated that,between 1 million and 200,000 years ago,the Homo lineage peaked in body size anddisplayed considerable brain growth rela-tive to body size.

Bones of the Jinniushan specimeninclude a skull with many upper-jaw teeth,six vertebrae, two left ribs, a left-forearmbone, and the left half of the pelvis.

Pelvic shape and proportions are those ofa female, the researchers conclude. Someresearchers had previously dubbed thisancient individual a male solely on the basisof its large, thick-boned skull.

Three other partial-fossil individualsfound in high-latitude, mid–Stone Agesites—two Neandertals and one of anotherHomo species—had wide torsos and shortlimbs, although to a lesser extent than theJinniushan specimen did, Rosenberg says.

The Chinese skeleton’s age estimatederives from measurements of radioactivematerial that accumulated in animal teethfound in the same sediment.

The new findings reinforce previous fos-sil analyses suggesting that mid–Stone Agehuman ancestors evolved cold-adaptedbodies at lower latitudes and in warmer cli-mates than modern people did, remarksanthropologist Erik Trinkaus of Washing-ton University in St. Louis.

In his view, that’s because mid–Stone Agefolk had less effective ways to protect them-selves from the cold than people did afterabout 60,000 years ago. At that time, camp-fires gave way to stone-lined hearths. Thenature of mid–Stone Age clothing and shel-ter is unknown, Trinkaus adds. —B. BOWER

Birth DeterrentStress hormone cited in early miscarriages

High concentrations of a stress hormonein newly pregnant women might makethem more likely to have miscarriages, anew study finds.

Roughly 30 to 50 percent of pregnan-cies end in miscarriage, says biologistPablo A. Nepomnaschy of the NationalInstitute of Environmental Health Sci-ences in Research Triangle Park, N.C. Thatnumber is imprecise because many mis-carriages occur within days of conception,before a woman knows that she is preg-nant. Miscarriage is a natural process thatevicts defective embryos that are unlikelyto survive, Nepomnaschy says, but thehigh rate suggests that other factors alsoplay a role.

A few previous studies examined the rela-tionship between miscarriage and stress,but their results were inconsistent. Nepom-naschy focused on extremely early preg-nancies in healthy women and measured abiochemical indicator of stress.

In high-stress circumstances—for exam-ple, energy deficit, infection, injury, or socialconflict—the body’s adrenal gland producesmore of the hormone cortisol. To testwhether cortisol concentrations are associ-ated with miscarriage, Nepomnaschyenlisted 61 married women in ruralGuatemala who weren’t using birth control.Over a year, each woman collected a urinesample every other morning right after shewoke up. Nepomnaschy and scientists at theUniversity of Michigan in Ann Arbor usedthese samples to assess each woman’s preg-nancy status and cortisol concentration.

There were 22 pregnancies during thestudy. In 9 of 10 pregnancies in which awoman’s cortisol concentrations hadjumped above her personal average duringthe first 3 weeks of gestation, a miscarriage

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LARGE LADY A new analysis of a partialStone Age skeleton, including this skull,identifies it as coming from the biggestknown female among human ancestors.

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