We studied early development of peer dominance relationships in a captive group of Japanese macaques Macaca fuscata fuscata at the Primate Research Institute of Kyoto University. This study aims to give detailed descr...We studied early development of peer dominance relationships in a captive group of Japanese macaques Macaca fuscata fuscata at the Primate Research Institute of Kyoto University. This study aims to give detailed descriptions on characteristic patterns of maternal rank acquisition from infant to juvenile. Focal subjects were 22 young monkeys belonging to three cohorts born in 2002, 2003 and 2005. Data were collected with a total 2130 sessions of 30-minute continuous recording of focal subjects combined with all occurrence-sampling methods. The onset of aggressive behavior varied per cohort and was delayed in cohorts with fewer close-aged associates. More than 60% of dyadic combinations in agonistic interactions between peers were unidirectional throughout the study period. Although some bidirectional interactions could have involved unstable relationships between particular individuals, most of the bidirectional interactions included a few continuous series of alternating one-sided interactions. A linear order could be found among peers from the first appearance of aggressive behavior, and nearly 90% of those dyads were concordant with that of their mother＇s rank order. Young males were responsible for most of the dominance relations that would not be predicted based on their mother＇s rank. These results suggest that infant monkeys may recognize their own social status relative to their opponent＇s before onset of aggressive behavior and adjust themselves into the matrilineal rank system accordingly.展开更多
In hand reared birds and mammals, it is generally considered that the development of hoarding behavior is the result of an interaction between the development and maturation of the nervous system and learning from ind...In hand reared birds and mammals, it is generally considered that the development of hoarding behavior is the result of an interaction between the development and maturation of the nervous system and learning from individual experience. How- ever, few studies have been done on wild animals. We tested differences in hoarding behavior between captive reared and wild individuals of two sympatric small rodents, Korean field mice Apodemus peninsulae and Chinese white-bellied rats Niviventer confucianus. Our aim was to identify if lack of experience from the wild would result in poorly developed hoarding behavior. The Korean field mice perform scatter- and larder-hoarding behaviors whereas Chinese white-bellied rats hoard food in larders only. Within outdoor enclosures we compared seed-hoarding behavior in reared juveniles （RJ, 40-50 d old, pregnant mothers were captured in the wild）, wild juveniles （WJ, as young as the RJ） and wild adults （WA, over-winter animals）. We found that a lack of experience from the wild had significant effects on seed-hoarding behavior for both species. The RJ-group removed and hoarded fewer seeds than the WJ- and WA-groups. The two latter groups hoarded seeds in a similar way. In the Korean filed mouse the ILl-group placed more seeds on the ground surface than other groups. These findings suggest that wild experience is important for the acquisition of an appropriate food-hoarding behavior （especially for scatter-hoarding） in these species展开更多
Male copulatory patterns, female multiple copulation and male post-copulatory guarding were studied in Eld＇s deer Cervus eldi in Datian National Nature Reserve, China. Mating behavior in 18 females and 11 males from ...Male copulatory patterns, female multiple copulation and male post-copulatory guarding were studied in Eld＇s deer Cervus eldi in Datian National Nature Reserve, China. Mating behavior in 18 females and 11 males from a group of 61 semi-captive Eld＇s deer were observed. The majority （55.8%） of copulations occurred between 15：00-19：00 h. The ejaculatory mount was preceded by an average of 5.1 prior mounts. Successful copulation consisted of a single thrust with ejaculation during one intromission, with no lock. This copulatory pattern is classified as pattern No. 15 （no lock, no intravaginal thrusting, single intromission, and multiple ejaculation） and No. 16 （no lock, no intravaginal thrusting, single intromission, and single ejaculation） under Dewsbury＇s scheme （1972） and as No. 16 （no lock, no thrusting, single and brief intromission） under Dixson＇s classification （1998）. Copulation frequency was 1.5 ± 0.9 times for males/females with the same female/male per day. The duration of the final mount, which included ejaculation, was brief （3.4±1.3 s）, and ejaculation usually terminated copulation. Eleven females copulated more than once in this study： three of them copulated with several males （multi-male copulations） and the remainder copulated with a single male （repeated copulations）. Our results indicate that some female Eld＇s deer may seek multiple copulations to be a strategy to improve the genetic quality of their offspring or to avoid harassment. Post-copulatory guarding of females by males followed all copulations, with dominant males guarding for significantly longer than subordinate males. Dominant males appear to be more effective at post-copulatory guarding than subordinate males. Subordinate males engaged in a quicker pre-copulatory phase to improve their chances of finishing copulation before being forced to accede to dominant males [Current Zoology 57 （3）： 284-292, 2011].展开更多
文摘We studied early development of peer dominance relationships in a captive group of Japanese macaques Macaca fuscata fuscata at the Primate Research Institute of Kyoto University. This study aims to give detailed descriptions on characteristic patterns of maternal rank acquisition from infant to juvenile. Focal subjects were 22 young monkeys belonging to three cohorts born in 2002, 2003 and 2005. Data were collected with a total 2130 sessions of 30-minute continuous recording of focal subjects combined with all occurrence-sampling methods. The onset of aggressive behavior varied per cohort and was delayed in cohorts with fewer close-aged associates. More than 60% of dyadic combinations in agonistic interactions between peers were unidirectional throughout the study period. Although some bidirectional interactions could have involved unstable relationships between particular individuals, most of the bidirectional interactions included a few continuous series of alternating one-sided interactions. A linear order could be found among peers from the first appearance of aggressive behavior, and nearly 90% of those dyads were concordant with that of their mother＇s rank order. Young males were responsible for most of the dominance relations that would not be predicted based on their mother＇s rank. These results suggest that infant monkeys may recognize their own social status relative to their opponent＇s before onset of aggressive behavior and adjust themselves into the matrilineal rank system accordingly.
文摘In hand reared birds and mammals, it is generally considered that the development of hoarding behavior is the result of an interaction between the development and maturation of the nervous system and learning from individual experience. How- ever, few studies have been done on wild animals. We tested differences in hoarding behavior between captive reared and wild individuals of two sympatric small rodents, Korean field mice Apodemus peninsulae and Chinese white-bellied rats Niviventer confucianus. Our aim was to identify if lack of experience from the wild would result in poorly developed hoarding behavior. The Korean field mice perform scatter- and larder-hoarding behaviors whereas Chinese white-bellied rats hoard food in larders only. Within outdoor enclosures we compared seed-hoarding behavior in reared juveniles （RJ, 40-50 d old, pregnant mothers were captured in the wild）, wild juveniles （WJ, as young as the RJ） and wild adults （WA, over-winter animals）. We found that a lack of experience from the wild had significant effects on seed-hoarding behavior for both species. The RJ-group removed and hoarded fewer seeds than the WJ- and WA-groups. The two latter groups hoarded seeds in a similar way. In the Korean filed mouse the ILl-group placed more seeds on the ground surface than other groups. These findings suggest that wild experience is important for the acquisition of an appropriate food-hoarding behavior （especially for scatter-hoarding） in these species
基金This research was supported by the Key Project in the National Science and Technology Pillar Program in the Eleventh Five-year Plan Period of China （Grant No. 2008BADBOB01）, and the National Natural Science Foundation of China （Grant No. 30770320）. We thank B. D. Bravery and Z.-Y. Jia for English editing and helpful comments on the manuscript, and we thank S.-Y. Li, Y.-Q. Wu, B. Long, E.-B. Zhang, H. Zhang and X. Wen of Datian National Nature Reserve for their assistance when we conducted fieldwork.
文摘Male copulatory patterns, female multiple copulation and male post-copulatory guarding were studied in Eld＇s deer Cervus eldi in Datian National Nature Reserve, China. Mating behavior in 18 females and 11 males from a group of 61 semi-captive Eld＇s deer were observed. The majority （55.8%） of copulations occurred between 15：00-19：00 h. The ejaculatory mount was preceded by an average of 5.1 prior mounts. Successful copulation consisted of a single thrust with ejaculation during one intromission, with no lock. This copulatory pattern is classified as pattern No. 15 （no lock, no intravaginal thrusting, single intromission, and multiple ejaculation） and No. 16 （no lock, no intravaginal thrusting, single intromission, and single ejaculation） under Dewsbury＇s scheme （1972） and as No. 16 （no lock, no thrusting, single and brief intromission） under Dixson＇s classification （1998）. Copulation frequency was 1.5 ± 0.9 times for males/females with the same female/male per day. The duration of the final mount, which included ejaculation, was brief （3.4±1.3 s）, and ejaculation usually terminated copulation. Eleven females copulated more than once in this study： three of them copulated with several males （multi-male copulations） and the remainder copulated with a single male （repeated copulations）. Our results indicate that some female Eld＇s deer may seek multiple copulations to be a strategy to improve the genetic quality of their offspring or to avoid harassment. Post-copulatory guarding of females by males followed all copulations, with dominant males guarding for significantly longer than subordinate males. Dominant males appear to be more effective at post-copulatory guarding than subordinate males. Subordinate males engaged in a quicker pre-copulatory phase to improve their chances of finishing copulation before being forced to accede to dominant males [Current Zoology 57 （3）： 284-292, 2011].
