That's not the same as rapid rises in temperature due to the greenhouse effect, "says Chang Yung-jen, a nature photographer who recently published a two-volume introduction and field guide to Taiwan's insects. He notes that many caterpillars pupate during the winter, and they often need to be exposed to low or even sub-zero temperatures before they are" willing "to finish their pupation and emerge as adults.
近來出版台灣《昆蟲入門》與《昆蟲圖鑑》的生態攝影者張永仁說，許多毛毛蟲以蛹過冬，往往需要凍過、冷過，才「心甘情願」化蛹而出。