A study that suggests that increased gamma band (~40 Hz) event-related synchronization is related to, but not sufficient for, consciousness.
Clelland et al. show that synthesis of new nerve cells contributes to formation of spatial memories.
I Heard That Coming: Bendixen et al. show that event related potentials can signal the predictability of pattern in an upcoming a tone sequence.
Watching whales watching us. The evidence suggesting association between sonar and whale deaths is very convincing.
Scientists have now documented behaviors like tool use and cooperative hunting strategies among whales. Orcas, or killer whales, have been found to mourn their own dead. Just three years ago, researchers at Mount Sinai School of Medicine in New York discovered, in the brains of a number of whale species, highly specialized neurons that are linked to, among other things, the use of language and were once thought to be the exclusive property of humans and a few other primates. Indeed, marine biologists are now revealing not only the dizzying variety of vocalizations among a number of whale species but also complex societal structures and cultures.
Vorauer et al. on multiculturalism versus avoidance in influencing the tone of dominant/minority group interactions.
David Sloane Wilson and collaborators on how nice guys can finish last. From the summary in Nature:
Selfish individuals can profit from the altruism of others in their group, and can even exploit a group's resources so much that the resources become exhausted — an event known as the tragedy of the commons...Omar Eldakar, of the University of Arizona in Tucson, and his colleagues have now shown experimentally that aggressive mating in water striders (Aquarius remigis) can result in one such tragedy. Harassment of female water striders by males has previously been shown to drive away females, diminishing the mating success of all males in a group...The team built pools and manipulated the number of aggressive and nonaggressive males in each. They found that hyperaggressive males had greater mating success than those which were not aggressive within mixed pools. But as the number of hyperaggressive insects increased, the mating success of both types decreased.