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A baby Rhino and it's mother play at a zoo in Hannover, Germany. Jochen Luebke/dapd/APJochen Luebke/dapd


The South African government says a record 668 rhinos were killed in the country in 2012, an increase of nearly 50 percent over the previous year. Demand is growing in Vietnam and elsewhere in Asia where rhino horn is believed to have medical benefits despite evidence to the contrary. The horn is made of keratin, a protein also found in human fingernails.