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1.
We measured the serum concentration of 25-hydroxyvitamin D3 (25-OH-D3) and 1,25-dihydroxyvitamin D3 (1,25-[OH]2-D3) in 23 different Platyrrhines from four different genera and in 21 Catarrhines from six different genera in residence at the Los Angeles Zoo. The mean (±S.E.) serum concentration of 1,25-(OH)2-D3 was significantly greater in Platyrrhines (810 ± 119 pg/ml) than in Catarrhines (61 ± 5 pg/ml), suggesting that high circulating concentrations of the active vitamin D hormone were a characteristic of New World primates in both the Cebidae and Callitrichidae family. This increase in the serum concentration of 1,25-(OH)2-D3 is probably an adaptational response on the part of Platyrrhini to offset a relative decrease in the concentration of specific receptor for 1,25-(OH)2-D3 in target tissues for the hormone.  相似文献   
2.
潘汝亮  彭燕章 《动物学报》1992,38(2):128-135
本文利用三维笛卡儿空间座标对菲氏叶猴(Presbytis phayrei)和黑叶猴(P.francoisi)颅骨的形态结构作了比较研究,描绘了它们的侧视和俯视投影图形。结果表明,两种投影图形均显示黑叶猴的颅骨大于菲氏叶猴,且显著性增大的区域出现在眉点、囟门、枕骨大孔附近和下颌骨体的高度。但菲氏叶猴较黑叶猴具有更凸的面颅。据枕骨隆突至眉点的侧视投影弧长,两种叶猴的数学模式均为:Y=a+bX-cX~2(R=0.92)。从侧视投影看,两种叶猴自枕骨隆突至眉点主要表出大小的不同。若据俯视投影图,两种颅骨的差异主要出现在外耳道以前的部分。黑叶猴较菲氏叶猴具有十分显著性增高的下颌骨体以及相对应更发达的咬肌和咀嚼器官,这很可能与它取食更多的果类食物有关。  相似文献   
3.
开展近缘物种觅食行为比较对理解动物的行为可塑性及适应性具有重要意义。白头叶猴(Trachypithecus leucocephalus)和黑叶猴(T.francoisi)是近缘物种,体形大小相近,社会结构和栖息环境相似,是广西崇左白头叶猴国家级自然保护区喀斯特季节性雨林中邻域分布的灵长类。为了探索两个物种在喀斯特生境中是否有相似的觅食策略,我们于2012年1-12月采用瞬时扫描取样法对两种叶猴的觅食行为进行研究。结果表明,白头叶猴与黑叶猴在不同时段均为叶食性,树叶是两种叶猴各个时段主要食物,其中白头叶猴日均取食树叶77.0%±4.4%,黑叶猴日均取食68.9%±8.3%,两者对树叶的采食比例均没有显著的日时段差异(白头叶猴:χ2=6.602,df=11,P=0.830;黑叶猴:χ2=11.393,df=11,P=0.411)。两种叶猴的觅食行为都在猴群清晨离开夜宿石洞后和进入过夜山洞前的时段中频繁发生。白头叶猴在09:00-10:59和16:00-17:59出现觅食高峰,时间占比分别为41.7%和46.3%;黑叶猴同样在09:00-10:59和16:00-17:59的时间段内发生高频率的觅食行为,时间占比分别为31.3%和38.0%。此外,两种叶猴的觅食时间在大部分时段中的差异并不明显。白头叶猴和黑叶猴在石灰岩生境中具有相似的觅食策略,这意味着两种叶猴在取食生态学上可能采取相似的保护措施。  相似文献   
4.
Little is known about the fate of adult male residents after they are ousted from bisexual one-male troops of Hanuman langurs (Presbytis entellus) in the course of adult male replacements. In a long term study at Jodhpur, Rajasthan, it was possible to reconstruct partial life histories of several ousted residents. One resident was killed during the male change. Ousted residents did not regain residency despite their continued invasions into bisexual troops. It is assumed that the males' chances to take over and to defend a troop are restricted to an age of 9–14 years, when the males are in prime physical condition. One male became solitary for some months while trying to regain residency of his old troop, before joining some “alien” males. As a rule, males are likely to rejoin their own male bands if they are ousted after short periods of residency. If the residency exceeds 3 months then the ongoing structural change in the former band may prevent their reintegration. However, in such cases, ousted residents which belonged to the same band may reunite and mingle with another male band which lacks prime males. Weaned sons may follow their fathers after ousting. In the case of numerous weaned offspring, fathers and sons may together form at least temporary new male bands.  相似文献   
5.
Previous studies of Trachypithecus species indicated that they were selective feeders that concentrated on relatively few food species/items. From January to December 2005, I quantified potential food availability and the food species/items eaten by five groups of François' langur (Trachypithecus francoisi) in the Mayanghe Nature Reserve (MNR), People's Republic of China. These langurs fed on 164 species, of which the top ten accounted for 51% of all feeding records. Langurs consumed more species (91) in the spring than in other seasons (73 summer, 75 autumn, and 67 winter), and only 38 species were consumed in all seasons. Nontree food species, such as bushes and lianas, accounted for 47% of the total feeding records and for a majority (68%) of the feeding records in winter. The annual diet consisted of leaves (64% of feeding records), fruit and seed (32%), and other nonfoliage items (4%); the langurs switched from being more folivorous in spring (93%) and summer (79%) to being more frugivorous in autumn (53%) and winter (56%). There was no correlation between the proportion of feeding records and the food availability in the most frequently consumed species, indicating that these langurs were selective feeders; there were significant correlations between consumption and abundance in both the entire set of 112 food species and the set of 86 infrequently consumed species, indicating that foods that are more available are eaten more frequently. It appeared that in the seasonal and disturbed habitat, feeding decisions and diet composition of the langur may be driven more by food availability, and less by animal's selectivity, than at other sites. The results indicate that François' langur copes with habitat alterations by broaden its dietary breadth; this has implications for the adaptive significance of dietary breadth, and has implications for future conservation strategies for species which exist in degraded habitats. Am. J. Primatol. 73:1176–1187, 2011. © 2011 Wiley Periodicals, Inc.  相似文献   
6.
笼养白头叶猴夏季水分摄入与消耗的初步研究   总被引:6,自引:0,他引:6  
黄乘明  卢立仁 《兽类学报》1997,17(2):100-106
叶片中的水分含量是白头叶猴水分的主要来源,占水分需求总量的83.68%,其它的16.32%来自于自由水。在笼养条件下,白头叶猴可饮用自来水,野生状态下,动物饮用露水或雨水。尽管饮水行为不是每天都有,但能经常观察到,特别是在夏季雨后.除了体表和呼吸系统的水分蒸发外,白头叶猴通过尿和粪便丢失的水分含量分别是44.68%和55.32%。  相似文献   
7.
黑叶猴和菲氏叶猴颅骨的比较研究   总被引:1,自引:0,他引:1  
  相似文献   
8.
The testicular histology of the dusky leaf monkey, Presbytis obscura,is described following a study of material from 16 adult males collected over a 13-month period in Peninsular Malaysia. The histological appearances were similar to those of the other cercopithecines studied so far. No seasonal variation in the height of the seminiferous epithelium was observed, and spermatogenesis was seen in all the adult testes. These findings suggest that males of this species are capable of breeding throughout the year. These results are discussed in relation to field observations of births of this species and to the birth patterns exhibited by other species of langur.  相似文献   
9.
贵州麻阳河地区黑叶猴的食性观察   总被引:20,自引:0,他引:20  
1995 ̄1997年对黑叶猴进行野处食性观察,结果表明:(1)对农作物的取食时间是影响其取食植物种类多少的主要因子;(2)其取食部位季节性明显;(3)各季节取食时间长短与了食农作物时间呈负相关;(4)各季节食物交叉性不强。  相似文献   
10.
We studied grooming among adults of a one-male multifemale troop of free-ranging Hanuman langurs (Presbytis entellus)living near Jodhpur, India, for 9 years. The 11–13 females devoted about 6% of their day to allogrooming. Adult males, whose tenures averaged 2.2 years, were transient figures in the troop's history, as reflected by their rather peripheral role in the grooming network. Females groomed males 4–40 times more frequently (1006 episodes) than vice versa- (176 episodes). Adult females received 97% of all grooming from other adult females (6655 episodes). Although females exhibited an age- inversed dominance hierarchy, they did not compete for grooming access to particular troop mates. Dyads of all possible rank differences occurred as frequently as expected: 51% of grooming was directed up the hierarchy and 49% down it. Young, high- ranking individuals gave and received significantly more grooming than the oldest, low- ranking females did. The pattern seemed to be influenced by kin selection because of the presumably high degree of female relatedness. They invested most in troopmates with the highest reproductive value, i.e., the youngest individuals. This trend was coupled with a preference of closest kin (mothers and daughters). Reciprocity was the outstanding feature since all adult females groomed and were groomed by all others. Such a tight social net might establish the necessary cohesion during frequent territorial disputes with neighboring troops.  相似文献   
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