Nature Podcast: Learning who to trust, how cooling bird brains slows down song, controlling quantum dots for computing, how entrepreneurs think, and a round-up of science news.

Top US court allows Navy sonar use

Environmentalists concerned over potential effects on whales.

Modified genes spread to local maize

Findings reignite debate over genetically modified crops.

Counting the human costs of conflict

Calculating the death toll from the crisis in the Democratic Republic of the Congo.