Criteria of Authentication (Hofreiter et al. 2001, Marota & Rollo 2002, Willerslev & Cooper 2005). Briefly, the distance between aDNA extraction or PCR preparation rooms of Building A and main PCR lab in Building B is about 60 meters. On 4th floor in Building A, there is not any lab performing PCR amplification of modern DNA. The rooms for aDNA extraction or PCR preparation were separated from our main lab where we did PCR works. The rooms were equipped with night UV irradiation, isolated ventilation, or laminated flow hood. The researchers in our lab should follow instructions in Criteria of Authenticity (Hofreiter et al. 2001, Marota & Rollo 2002, Willerslev & Cooper, 2005). None could enter into aDNA extraction or PCR preparation rooms without permission.