The issue focused on climate change and scientists had concerns about scientific literature that researchers used to research science. Scientists such as physicist Carl Sagan would often argue that studies could not tell us whether there is an inherent biological difference between humans and other animals. Science researchers took science seriously, said biologist Bruce Evans of NASA's Goddard Space Flight Center in Greenbelt, Md., who worked with biologists at NASA Ames Research Center in Moffett Field, Calif. "There are things scientists know," he said. Scientists should research scientifically if they