A recent Nature poll of 1,000 biomedical researchers from around the world shows that while 90 percent of them say research on animals is "essential," 16 percent say they have "misgivings" about using animals, and 33 percent had "ethical concerns" about the role animals play in their research. However, Nature's Daniel Cressey says, it seems that the impact of animal activism on researchers isn't as broad as it may seem.