Figala J, Tester J R
Department of Environmental Protection, Agricultural University, Prague.
Prog Clin Biol Res. 1990;341B:793-807.
Influences of seasonal changes on the circadian system were observed in studies of feeding activity in four species of ducks and of feeding and locomotor activity in two species of mammals kept in captivity in the natural LD cycle. Feeding and locomotor oscillators had different sensitivities to exogenous synchronizers. Changes from a circadian to an ultradian feeding rhythm occurred as a result of courtship and breeding behavior in two duck species. Different phases of feeding rhythms in ducks were shown to have important ecological consequences for establishing the species in appropriate time niches in agricultural wetlands. Detailed study of annual, seasonal and daily rhythms of feeding and locomotion measured simultaneously in captivity and in free-ranging animals is necessary to elucidate the structure and function of food chains and webs. Activity rhythms of both producers and consumers (predators and prey) during daily and annual cycles is of special concern. This contribution of chronobiology will further our understanding of the niche of selected species in agricultural ecosystems.
在对自然光照-黑暗周期下圈养的四种鸭的摄食活动以及两种哺乳动物的摄食和运动活动进行研究时，观察到了季节变化对昼夜节律系统的影响。摄食和运动振荡器对外源性同步器具有不同的敏感性。两种鸭在求偶和繁殖行为期间，摄食节律从昼夜节律转变为超昼夜节律。鸭摄食节律的不同阶段对于在农业湿地的适宜时间生态位中确立物种具有重要的生态意义。有必要对圈养和自由放养动物同时测量的摄食和运动的年度、季节和每日节律进行详细研究，以阐明食物链和食物网的结构与功能。生产者和消费者（捕食者和猎物）在每日和年度周期中的活动节律尤其值得关注。时间生物学的这一贡献将增进我们对农业生态系统中特定物种生态位的理解。
