Royal Thai Marine Chief Petty Officer 1st Class Pairoj Prasansai, right, feeds cobra blood, which can be a useful source of energy, to U.S. Marine Corps Sgt. Jerry Clark during a jungle survival course in Ban Chan Krem, Chantaburi province, Kingdom of Thailand, Feb. 17, 2013. The class was to help teach U.S. Marines basic jungle survival techniques as part of Exercise Cobra Gold 2013.