This week, we chat about cement’s shrinking carbon footprint, commuting hazards for ancient Egyptian artisans, and a new bipartisan group opposed to government-funded animal research in the United States with Online News Editor David Grimm. Plus, Science’s Alexa Billow talks to news writer Sam Kean about the kinds of data that can only be gathered at night as part of the special issue on circadian biology.  Listen to previous podcasts.  [Image: roomauction/iStockphoto; Music: Jeffrey Cook]