【摘要】 动物的部分身体结构和功能特征在生长发育过程中雌、雄两性之间出现差异,即产生性二型现象。动物体型的性二型现象是自然界长期进化和动物适应环境变化的结果,具有重要的进化学和生态学意义。麋鹿Elaphurus davidianus是典型的性二型哺乳动物。本文对147头麋鹿(♀57头,♂90头),幼体、亚成体和成体及0~4岁以上雌性5个年龄段、0~5岁以上雄性6个年龄段的14个体型参数进行测量分析。结果表明:北京南海子麋鹿种群幼体不存在体型性二型现象;各体型参数中,体质量的体型性二型现象最明显,其性二型指数在幼体、亚成体和成体3个发育阶段分别为0.995、1.381和1.423,显著递增;0~2岁期间麋鹿生长发育迅速,但不存在雌、雄两性之间的显著差异;雌性麋鹿1~2岁达到性成熟,3岁达到成年;雄性麋鹿5岁以上达到成年。受食物状况、种群密度、气候条件、温度等生境因子的影响,麋鹿体型大小和体型性二型性指数存在区域差异。更多还原

【Abstract】 Sexual dimorphism was a common biological phenomenon that originated from the differences of body structures and function characteristics between males and females during their growth processes. Sexual dimorphism was the result of natural selection and adaption to the difficult and brutal environments,thus it was important to the studies of ecology and evolution. Père David’s deer( Elaphurus davidianus) was a typical sexual dimorphism mammal. A total of 147( ♀57,♂90) individuals,including 5 female groups( 0 yr,1 yr,2 yrs,3 yrs and ≥4 yrs) and 6 male groups( 0 yr,1 yr,2 yrs,3 yrs,4 yrs and ≥5 yrs) were used in this study; 14 body size parameters such as body weight( BW),body length( BW),head length( HL),forehead size width( FHW),shoulder height( SH),body slope length( BSL),hind-foot length( HFL),forehead leg circle( FLC),chest circle( CC),abdominal perimeter( AP),tail length( TL),ear length( EL),chest depth( CD),chest width( CW) were measured from January 2010 to May 2014. The results showed that there was no sexual dimorphism of the newborn. BW was the most striking feature among the all,and the male / female ratios of BW in newborn,sub-adult and adult was 0. 995,1. 381 and 1. 423,respectively. No significant difference was observed between the growth rate of 0 ~ 2 yrs deer. The females reached sexual maturity at 1 ~ 2 yrs,and became adults at 3 yrs,while the males became adults after 5 yrs. The body size and index of sexual dimorphism varied among biogeographic regions,as the ecological factors such as food,density,climate,temperature and so on varied.更多还原