Li Jin-Fa, He Yu-Chao, Huang Zhi-Pang, Wang Shuang-Jin, Xiang Zuo-Fu, Zhao Juan-Jun, Xiao Wen, Cui Liang-Wei
Key Laboratory of Forest Disaster Warning and Control in Yunnan Province, Southwest Forestry University, Kunming, Yunnan 650224, China.
Bureau of Yunling Provincial Nature Reserve, Lanping, Yunnan 671400, China.
Dongwuxue Yanjiu. 2014 Nov 18;35(6):474-84. doi: 10.13918/j.issn.2095-8137.2014.6.474.
Seasonal variation in environmental factors is vital to the regulation of seasonal reproduction in primates. Consequently, long-term systematic data is necessary to clarify the birth seasonality and pattern of primates in highly seasonal environments. This study indicated that black-and-white snub-nosed monkeys (Rhinopithecus bieti) at Mt. Lasha exhibited strict birth seasonality with a pulse model. Infants were born with a certain degree of synchronization. Birth distribution showed three birth peaks, and the birth pattern showed a "V" style in even-numbered years and a gradual increase in odd-numbered years. The beginning date, end date and median birth date were earlier in even-numbered years than those in odd-numbered years. The higher latitude of their habitats, earlier birth date, shorter birth period, fewer birth peaks and stronger birth synchrony might be adaptations for strongly seasonal variation in climate and food resources. After the summer solstice when daylight length began to gradually shorten, R. bieti at Mt. Lasha started to breed during the period with the highest environmental temperature and food availability, which implied that photoperiod may be the proximate factor triggering the onset of estrus and mating. It appears that R. bieti coincided conception and mid-lactation with the peak in staple foods, and weaning with the peak in high quality of foods. Thus, food availability was the ultimate factor regulating reproductive seasonality, and photoperiod was the proximate factor fine-turning the coordination between seasonal breeding and food availability.
环境因素的季节性变化对于灵长类动物季节性繁殖的调节至关重要。因此，需要长期的系统数据来阐明高度季节性环境中灵长类动物的出生季节性和模式。本研究表明，拉山的黑白仰鼻猴（Rhinopithecus bieti）表现出严格的出生季节性，呈脉冲模式。幼崽出生具有一定程度的同步性。出生分布呈现三个出生高峰，偶数年的出生模式呈“V”形，奇数年则逐渐增加。偶数年的开始日期、结束日期和出生中位数日期均早于奇数年。它们栖息地的纬度较高、出生日期较早、出生期较短、出生高峰较少以及出生同步性较强，可能是对气候和食物资源强烈季节性变化的适应。夏至后，当白昼长度开始逐渐缩短时，拉山的黑白仰鼻猴在环境温度和食物可获得性最高的时期开始繁殖，这意味着光周期可能是触发发情和交配开始的近端因素。看来，黑白仰鼻猴的受孕和泌乳中期与主食高峰期重合，断奶与优质食物高峰期重合。因此，食物可获得性是调节繁殖季节性的最终因素，而光周期是微调季节性繁殖与食物可获得性之间协调的近端因素。
