Q&A: Observing the scars of the Arctic thaw

Ecologist Breck Bowdon talks about the consequences of thawing permafrost in Alaska.

Chief scientist quits California stem-cell agency

Departure raises questions over leadership at flagship centre.

Lawsuit puts flu-vaccine contract in doubt

Biotech company sued by creditors.

Vital marine habitat under threat

Destruction of seagrass on a par with loss of rainforests and coral reefs.