Fig. 1

Narrowed minds, thinking alike

By Zak Stambor

Graphic by Allen Carroll

The Internet gives researchers unprecedented access to scholarly work, but Chicago sociologist James Evans finds that it also leads them to cite fewer and newer articles. For a July 18 Science study, he examined 34 million articles, comparing their citations between 1945 and 2005 to their online availability from 1998 to 2005. For each year of back issues a journal posted online, the average age of referenced articles fell by a month; the drop was more precipitous for free papers than those charging a fee. “More is available, but less is sampled,” says Evans, who relates the dichotomy to online search habits versus library-index browsing. The tendency is most pronounced in life sciences—fast-growing fields with lots of information to cut through. Web searches are efficient, Evans concludes, but may “accelerate consensus and narrow the range of findings and ideas built upon.”