Common Cuckoos(Cuculus canorus)dependent on parental care for post-hatching demonstrate an intriguing ability to modify their begging vocalizations to ensure maximum care and resources from their interspecific foster ...Common Cuckoos(Cuculus canorus)dependent on parental care for post-hatching demonstrate an intriguing ability to modify their begging vocalizations to ensure maximum care and resources from their interspecific foster parents.Here,we compared begging calls of the Common Cuckoo nestlings fed by four host species,the Grey Bushchat(Saxicola ferreus),Siberian Stonechat(Saxicola maurus),Daurian Redstart(Phoenicurus auroreus),and Oriental Magpie-robin(Copsychus saularis).Results showed that begging calls of the stonechat-,redstart-,and robin-cuckoo resemble those of host species'nestlings in various aspects like low frequency,high frequency,frequency bandwidth and peak frequency,while the bushchat-cuckoo chicks'begging calls were only comparable to their host species in terms of how long they lasted and their peak frequency.In addition,cuckoo nestlings raised in different host nests displayed significant variations in their begging calls in low and peak frequency.This study suggests that cuckoo nestlings do not mimic host species nestlings'begging calls throughout the nestling period,but may tune their begging calls according to host species,while begging calls vary with cuckoo and host species nestlings'ages.Future research should study the parents'reactions to these calls in different host species for a better understanding of the mechanisms underlying such adaptations.展开更多
以呼伦贝尔沙地樟子松人工林为研究对象,利用树木年轮学和解析木法,推算过去41年樟子松林的生物量和年净初级生产力,并分析年净初级生产力与气温、降水、湿度等气象因子的关系。研究表明:随着林龄的增加,樟子松林生物量变化符合逻辑斯...以呼伦贝尔沙地樟子松人工林为研究对象,利用树木年轮学和解析木法,推算过去41年樟子松林的生物量和年净初级生产力,并分析年净初级生产力与气温、降水、湿度等气象因子的关系。研究表明:随着林龄的增加,樟子松林生物量变化符合逻辑斯蒂生长方程;樟子松林生物量从1977年的4.83 t/hm^(2)到2017年的167.95 t/hm^(2)。樟子松林净初级生产力年际差异较大,呈先增加后减小、最后趋于稳定的趋势,多年平均净初级生产力为4.08 t hm^(-2) a^(-1),最高达到6.13 t hm^(-2) a^(-1),最低为2.63 t hm^(-2) a^(-1)。气候因子与樟子松林净初级生产力关系较为密切,并具有一定的"滞后效应";樟子松林净初级生产力与上一年8月、12月和当年3月的降水量显著相关;净初级生产力与上一年和当年8—9月的月均湿度极显著正相关;净初级生产力与各月温度均呈不同程度的负相关,尤其是上一年和当年的6—9月温度显著影响着净初级生产力。研究表明,樟子松林净初级生产力受温度和降水的综合影响,净初级生产力与气候因子的关系属于温度敏感型,未来该地区持续升温的条件下樟子松林净初级生产力可能会降低。展开更多
基金supported by the National Natural Science Foundation of China(Nos.32270526 to W.L.and 32260253 to L.W.)supported by the specific research fund of The Innovation Platform for Academicians of Hainan Provincesupported by the Hainan Province Postdoctoral Research Project。
文摘Common Cuckoos(Cuculus canorus)dependent on parental care for post-hatching demonstrate an intriguing ability to modify their begging vocalizations to ensure maximum care and resources from their interspecific foster parents.Here,we compared begging calls of the Common Cuckoo nestlings fed by four host species,the Grey Bushchat(Saxicola ferreus),Siberian Stonechat(Saxicola maurus),Daurian Redstart(Phoenicurus auroreus),and Oriental Magpie-robin(Copsychus saularis).Results showed that begging calls of the stonechat-,redstart-,and robin-cuckoo resemble those of host species'nestlings in various aspects like low frequency,high frequency,frequency bandwidth and peak frequency,while the bushchat-cuckoo chicks'begging calls were only comparable to their host species in terms of how long they lasted and their peak frequency.In addition,cuckoo nestlings raised in different host nests displayed significant variations in their begging calls in low and peak frequency.This study suggests that cuckoo nestlings do not mimic host species nestlings'begging calls throughout the nestling period,but may tune their begging calls according to host species,while begging calls vary with cuckoo and host species nestlings'ages.Future research should study the parents'reactions to these calls in different host species for a better understanding of the mechanisms underlying such adaptations.
文摘以呼伦贝尔沙地樟子松人工林为研究对象,利用树木年轮学和解析木法,推算过去41年樟子松林的生物量和年净初级生产力,并分析年净初级生产力与气温、降水、湿度等气象因子的关系。研究表明:随着林龄的增加,樟子松林生物量变化符合逻辑斯蒂生长方程;樟子松林生物量从1977年的4.83 t/hm^(2)到2017年的167.95 t/hm^(2)。樟子松林净初级生产力年际差异较大,呈先增加后减小、最后趋于稳定的趋势,多年平均净初级生产力为4.08 t hm^(-2) a^(-1),最高达到6.13 t hm^(-2) a^(-1),最低为2.63 t hm^(-2) a^(-1)。气候因子与樟子松林净初级生产力关系较为密切,并具有一定的"滞后效应";樟子松林净初级生产力与上一年8月、12月和当年3月的降水量显著相关;净初级生产力与上一年和当年8—9月的月均湿度极显著正相关;净初级生产力与各月温度均呈不同程度的负相关,尤其是上一年和当年的6—9月温度显著影响着净初级生产力。研究表明,樟子松林净初级生产力受温度和降水的综合影响,净初级生产力与气候因子的关系属于温度敏感型,未来该地区持续升温的条件下樟子松林净初级生产力可能会降低。
