Animal populations and the stock market are hard to forecast. Both are generated by complicated, interdependent systems. Unlike financial stocks, where trades are meticulously recorded, scientists began estimating animal populations only a few decades ago.

Using advanced mathematical modeling, researchers from Sweden and The Netherlands show in an article in the August issue of the American Naturalist that this statement is sometimes true.

Researchers at the University of Missouri-Columbia are studying the status of black bears in Missouri. Black bears were abundant in the state during the 18th and 19th centuries, but have been considered almost extinct in Missouri since the late 19th century. The results of the MU study will be used by the Missouri Department of Conservation to help manage Missouri's black bear population.

Climate change could trigger "boom and " population cycles that make animal species more vulnerable to extinction. , according to Christopher C. Wilmers, an assistant professor of environmental studies at the University of California, Santa Cruz.