8.2 ka BP cooling event China Constructing Frames of Reference Early Neolithic East Asia Hokkaido Jomon Jomon people Korean Peninsula Neolithic Taiwan North China Paleolithic Taiwan Paleolithic–Neolithic transition Pleistocene to Holocene transition Yayoi adaptive strategy agricultural adoption aquatic utilization aquatic-focused foraging broad spectrum revolution bronze age climate fluctuation complex hunting–gathering dry-field farming first farmers hunter gatherers hunter–gatherers initial Holocene interaction invasion theory