Infanticide by males is a common phenomenon in mammals,especially primates,as lactation lasts much longer than gestation in many species.Usually,infanticidal episodes occur soon after group takeovers,and are tradition...Infanticide by males is a common phenomenon in mammals,especially primates,as lactation lasts much longer than gestation in many species.Usually,infanticidal episodes occur soon after group takeovers,and are traditionally considered a male reproductive strategy(i.e.,support the sexual selection hypothesis,Hrdy,1974).To verify the validity of this conception,we observed one group of François’langurs in the Nonggang Nature Reserve,China,between August 2003 and July 2004.During the study period,a François’langur female with the youngest infant in the group was attacked three times by immigrating males,and later disappeared by the third day after the final attack.We suggest that these attacks on the female-infant dyad represent infanticide attempts by males,and may be the cause of the adult female and her infant’s disappearance.Presumably,that female dispersed with her infant to avoid infanticide and was not killed.Though these observations do not completely verify the sexual selection hypothesis,they are not inconsistent with it.展开更多
Ranging behavior is an important aspect of animal behavior that researchers use to investigate ecological influences on individual behavior.We collected data on the ranging behavior of one group of François’lang...Ranging behavior is an important aspect of animal behavior that researchers use to investigate ecological influences on individual behavior.We collected data on the ranging behavior of one group of François’langurs(Trachypithecus francoisi)between August 2003 and July 2004 in a limestone habitat within Nonggang Nature Reserve,China.We evaluated the influences of food availability,water resources and sleeping sites on ranging behavior.During the study period,the total home range size for the study group was 64.5 or(69.3 ha if the lacunae within the borders in which langurs were not observed were included),and the mean daily path length was 541 m.These are well within the range of variation reported in Trachypithecus species.The monthly range size was between 9.8 and 23.3 ha,and monthly range size correlated negatively with young leaf availability.The langurs tended to use a larger range size during young leaf-lean periods.The langurs did not use their home range uniformly,and 74%of their activities occurred within 35%of their home range.The most heavily used quadrats in the home range were located near the most frequently used sleeping sites,suggesting that sleeping sites have a significant influence on the ranging behavior of François’langurs in limestone habitats.展开更多
基金supported by National Nature Science Foundation of China(31172122)Guangxi Nature Science Foundation(2012GXNSFAA053039)。
文摘Infanticide by males is a common phenomenon in mammals,especially primates,as lactation lasts much longer than gestation in many species.Usually,infanticidal episodes occur soon after group takeovers,and are traditionally considered a male reproductive strategy(i.e.,support the sexual selection hypothesis,Hrdy,1974).To verify the validity of this conception,we observed one group of François’langurs in the Nonggang Nature Reserve,China,between August 2003 and July 2004.During the study period,a François’langur female with the youngest infant in the group was attacked three times by immigrating males,and later disappeared by the third day after the final attack.We suggest that these attacks on the female-infant dyad represent infanticide attempts by males,and may be the cause of the adult female and her infant’s disappearance.Presumably,that female dispersed with her infant to avoid infanticide and was not killed.Though these observations do not completely verify the sexual selection hypothesis,they are not inconsistent with it.
基金This study is sponsored by the National Nature Science Foundation of China(No.39960015,30560023,30860050)the Chinese Academy of Sciences 100 Talent Program,the Monitoring and Conservation of Langur Project of the National Forestry Administration of China,the Guangxi Science Foundation(0991095)and the Project of the Creative Team from Colleges and Universities in Guangxi.We thank the Guangxi Forestry Bureau and the Nonggang Nature Reserve Administration Bureau.
文摘Ranging behavior is an important aspect of animal behavior that researchers use to investigate ecological influences on individual behavior.We collected data on the ranging behavior of one group of François’langurs(Trachypithecus francoisi)between August 2003 and July 2004 in a limestone habitat within Nonggang Nature Reserve,China.We evaluated the influences of food availability,water resources and sleeping sites on ranging behavior.During the study period,the total home range size for the study group was 64.5 or(69.3 ha if the lacunae within the borders in which langurs were not observed were included),and the mean daily path length was 541 m.These are well within the range of variation reported in Trachypithecus species.The monthly range size was between 9.8 and 23.3 ha,and monthly range size correlated negatively with young leaf availability.The langurs tended to use a larger range size during young leaf-lean periods.The langurs did not use their home range uniformly,and 74%of their activities occurred within 35%of their home range.The most heavily used quadrats in the home range were located near the most frequently used sleeping sites,suggesting that sleeping sites have a significant influence on the ranging behavior of François’langurs in limestone habitats.