A Lens On History: Advances in DNA technology have given scientists a new tool with which to study ancient human origins. "I think ancient DNA becomes very powerful" now, says one researcher, "because it gives you a direct look into the past." Here, a photographer shoots a reconstruction of a Neanderthal man at a museum in Germany. Sebastian Willnow/AFP/Getty Images hide caption

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An electric vehicle charging station in San Francisco. With sales of electric and plug-in hybrid cars expected to increase in coming years, a regional agency has set aside $5 million to increase the number of electric car charging stations to 5,000 around the Bay Area, up from 120 currently. Justin Sullivan/Getty Images hide caption

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Sierra Club activists wearing flags, representing more than 20 countries, take part in a protest by hiding their heads in the sand in Cancun last week. The group said countries participating in the United Nations Framework Convention on Climate Change in Cancun are not doing enough to stop climate change. AP hide caption

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Climate scientists and environmental advocates face an uphill battle as more Americans deny that global warming is real despite scientific evidence to the contrary. Here, a Greenpeace member checks the inside of a hot air balloon before it's launched in Cancun, Mexico. Luis Perez/AFP/Getty Images hide caption

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This sculpture of a Homo neanderthalensis adult male represents Neanderthals that lived between 225,000 and 28,000 years ago. It is a reconstruction based on Shanidar 1, made for the Smithsonian Human Origins Initiative. John Gurche, sculptor, Chip Clark, photographer/Smithsonian Human Origins Initiative hide caption

itoggle caption John Gurche, sculptor, Chip Clark, photographer/Smithsonian Human Origins Initiative

A bladder at a camp in Port-au-Prince holds fresh water. Sanitation and clean water are key to staving off cholera, and public health officials are launching a massive education effort using text messages and radio broadcasts. Christopher Joyce/NPR hide caption

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Two trucks crashed on a road toward Saint-Marc in Haiti. One truck was carrying Coke bottles, the other was full of people. The head-on collision knocked the bed off the back of one truck, killing several and injuring many more. Christopher Joyce/NPR hide caption

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Philomena Josephat and her father Joseph at St. Nicholas Hospital. Joseph, who has recovered from cholera, said: "I've never felt sick like that before, but I lost a child, and since then my health left me. And with this, that's even worse. I felt like I was dying." Carl Thalemaque for NPR hide caption

itoggle caption Carl Thalemaque for NPR

A banner in a street in Port-au-Prince urges people to wash with soap. Though the cholera epidemic has stabilized for now, health officials are working to contain and quell the outbreak and warn that the epidemic is not yet over. Nicholas Kamm/AFP/Getty Images hide caption

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A worker with Home Energy Loss Professionals, a Maryland company, retrofits the attic of a home. John Poole/NPR hide caption

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Scientists discovered stones for grounding flour in Italy used 30,000 years ago by hunter gatherers. Istituto Italiano di Preistoria e Protostoria hide caption

itoggle caption Istituto Italiano di Preistoria e Protostoria

Inside Veolia Energy's Plant Three in Baltimore, blue pipes carry chilled water that will be sent out to cool nearby buildings. The green pipes carry condensed water that removes heat from the chilling system, and orange pipes carry a refrigerant. The yellow pipes are for a future cooling system. Mike Ruocco/NPR hide caption

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Retired Coast Guard Adm. Thad Allen testifies Monday before the commission investigating the Gulf of Mexico oil spill. Though Allen was the government's leader of the spill response, he acknowledged it was not always clear to the public who was in charge. Mark Wilson/Getty Images hide caption

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A male Florida panther walks down Jane's Scenic Drive in Fakahatchee Strand Preserve State Park. Before scientists bred the Florida panthers with cats from Texas, they lacked vitality and were near extinction. Science/AAAS hide caption

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