The University of Chicago Magazine

April 1997



All Creatures Great and Small.

Scientists have long accepted paleontologist Edward Cope's 1871 proposition that as organisms evolve, they get bigger. Then in 1987 paleontologist David Jablonski decided to test Cope's rule with hard facts. After ten years of measuring some 6,000 mollusk fossils--1,086 species of clams, snails, whelks, and scallops that lived in North America over the last 16 million years of the Cretaceous period--Jablonski concluded that evolving organisms no more tend to become bigger than they do to become smaller (see January 16 Nature). Grouping the mollusk species into 191 evolutionary lineages, he found that 27 to 30 percent of the lineages showed an overall body-size increase, while an equal percentage decreased in overall body size. In another 28 percent, bigger species got bigger, while smaller species got smaller. And in 9 percent of lineages, all species decreased in size. Size, says Jablonski, "plays such a complex role in the larger evolutionary scale that there is no long-term, overarching pattern."

Armed Response.

Many Americans would like to see guns regulated much like other consumer products, according to a survey conducted by Johns Hopkins University's Center for Gun Policy and Research and the National Opinion Research Center. Of 1,200 people surveyed, 86 percent supported laws requiring all new handguns to be childproofed; 81 percent favored mandatory registration of handguns; and 70 percent wanted handgun owners to be licensed and trained. Three out of four people believed the government should regulate the safety design of guns.

Money Isn't Everything.

No wonder that poor children are called disadvantaged. Compared to rich kids, they're more likely to develop behavior problems, score lower on standardized tests, drop out of school, and need public assistance as adults. In What Money Can't Buy: Family Income and Children's Life Chances (Harvard), associate public-policy professor Susan E. Mayer asks whether low income itself is the culprit, or if the factors causing low income matter more. She concludes that "once children's basic material needs are met, characteristics of their parents become more important to how they turn out than anything additional money can buy." Thus, Mayer argues, additional aid should go to help poor parents with education, job training, and treatment for problems such as drug abuse, depression, or poor health.

More Investigations:

  • Medium and the Message:
    Art historian Wu Hung pulls back the veil of mystery surrounding Chinese painting.
  • Good Medicine:Professor of medicine Wendy Levinson finds that doctors who take time to talk with their patients are less likely to be sued for malpractice.
  • Precarious Balance:The carbon dioxide released from fossil fuels could linger in the atmosphere for thousands of year, causing dramatic climate changes, according to research by geophysicist David Archer.

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