A team of biologists places comb jellies, not sponges, at the base of a new tree of animal life. (p. 214)

A twisted joint might have made all the difference to scurrying crabs as they diverged from their clunky lobsterlike brethren. (p. 205)

New fossil finds suggest that the complex features of mammals originated earlier than previously thought and might even have evolved independently in different mammalian lineages. (p. 154)

Results of a new study using hypnosis may shed light on the process of memory retrieval and the potential for one part of the brain to block it. (p. 20)