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动物学研究 , 2000,
Abstract: Adult grass lizards,Takydromus septentrio nalis,are similar in size (SVL) but sexually dimorphic in head size (males' larger than females') throughout its range.A comprehensive analysis on the ecological and evolutionary sources of sexual differences in growth and size of heads requires a detailed understanding of growth trajectories during ontogeny.In this study,we specifically quesioned at what point during ontogeny males and females diverge in head size:at birth,during juvenile growth,or as mature adults? Our results indicate that males and females begin to diverge in head size at birth,although the divergence in the newly emerged young is much less pronounced than that in adults.An ANCOVA indicates that adult females even have smaller heads than do juveniles (including the newly emerged young).This suggests that adult females partition less resources into head growth but more into carcass growth,thereby leaving a larger space for eggs so as to increase reproductive output.Lizards collected in different seasons,from different populations,and at different ontogenetic stages,in various degrees,differ in food niche width and breadth.However,no direct evidence shows a substantial contribution of the divergence in head size to the segregation of food niche between males and females.Our analyses support that sexual selection is the main evolutionary source of smaller heads in female T.septentrionalis.
Sexual size dimorphism and female reproduction in the white-striped grass lizard Takydromus wolteri  [cached]
Laigao LUO, Yilian WU, Zhuyuan ZHANG, Xuefeng XU
Current Zoology , 2012,
Abstract: Sexual size dimorphism (SSD) has long attracted the attention of biologists, and life-history variation is thought to play an important role in the evolution of SSD. Here we quantified SSD and female reproductive traits to identify potential associations between SSD and female reproduction in the white-striped grass lizard Takydromus wolteri. In a population from Chuzhou, China, the largest male and female were 53.0 mm and 57.5 mm in snout-vent length (SVL), respectively. Females were larger in SVL and abdomen length, whereas males were larger in head size and tail length. Females produced up to five clutches of eggs during the breeding season, with large females producing more clutches and more eggs per clutch than small ones. As a result, large females had a higher annual fecundity and reproductive output. Egg size was positively correlated with maternal SVL in the first clutch, but not in subsequent clutches. These results suggest that T. wolteri is a species with female-biased SSD, and that fecundity selection, in which large females have higher fecundity due to their higher capacity for laying eggs, is likely correlated with the evolution of SSD in this species [Current Zoology 58 (2): 236-243, 2012].
The distribution and frequency of endocrine cells in the splenic lobe of grass lizard (Takydromus wolteri): An immunohistochemical study  [cached]
S-K Ku,H-S Lee
European Journal of Histochemistry , 2004, DOI: 10.4081/917
Abstract: The regional distribution and frequency of the pancreatic endocrine cells in the splenic lobe of grass lizard, Takydromus wolteri, were studied by immunohistochemical (PAP) method using six types of specific mammalian antisera against bovine Sp-1/chromogranin (bCG), serotonin, insulin, glucagon, somatostatin and human pancreatic polypeptide (hPP). The pancreas was subdivided into two regions – islet kike and exocrine regions. The frequency of each immunoreactive (IR) endocrine cells was calculated as mean number/total 100 islet cells and as mean number/total 1000 cells (including exocrine and endocrine cells) using automated image analysis process. In addition, the percentage of each IR cell was also calculated. All of six endocrine cells were demonstrated. They were dispersed in the whole pancreatic parenchyma between exocrine acinar cells, or they were also observed as islet like clusters. In islet-like regions, bCG-, insulin- and glucagon-IR cells were detected as one or two cell layer cords and they were located between this cell-cords with 14.30±5.62, 61.50±9.76 and 26.50±9.31/100 cells frequencies, respectively. However, somatostatin-IR cells were mainly located in the peripheral parts not in cell-cords with 12.40±4.86/100 cells, and no serotonin- and hPP-IR cells were demonstrated. In exocrine regions, all of bCG-, serotonin-, insulin-, glucagon-, somatostatin- and hPP-IR cells were detected and they occurred mainly among the exocrine parenchyma as solitary cells with 10.30±2.54, 0.80±0.63, 15.50±5.30, 5.80±2.66, 3.10±1.29 and 11.00±3.33/1000 cells frequencies, respectively. In addition, serotonin-IR cells were mainly located between epithelia and connective tissue of pancreatic duct. Overall, there were 0.58±0.49% serotonin–, 56.44±9.35% insulin–, 23.73±8.22% glucagon–, 11.28±3.03% somatostatin– and 7.97±2.02% hPP-IR cells

LIN Zhi,hua,JI Xiang,

动物学研究 , 1998,
Abstract: 北草晰孵化孵化基质吸收水分导致质量增加。24℃湿度对孵化卵的终末质量无显著影响;26℃和28℃时,高湿度孵化的卵终末质量较大。孵化卵终末重与初始重呈正相关,终末卵重的差异部分地由初始卵重决定。
Utilization of Lipid in Northern Grass Lizards Takydromus septentrionalis in Hangzhou in the Breeding Season

DU Wei-guo,LU Yi-wei,JI Xiang,

动物学研究 , 2003,
Abstract: Adult northern grass lizards (Takydromus septentrionalis) were collected at Mt.Xiaohe,Hangzhou in three periods of the breeding season,2001.They were dissected to determine sex,and storages of lipids in abdominal fat bodies,carcass,tail and liver.According to the stage of egg development (non-vitellogenetic follicles,yolked follicles,and oviductal eggs),females started vitellogenesis in later March (T1),produced eggs of the first clutch in early May (T2),and partly (37% of the sex) ceased reproduction in mid-June (T3).From T1 to T2,the abdominal fat body of females decreased from 17.3 mg on average to zero,and that of males changed from 6.3 mg to 0.8 mg.The decline of the lipid in females was 3 times of that of males.However,there was no significant change in lipid contents of the carcass,tail and liver in the three periods.It is very likely that the abdominal fat body of females is used for the first clutch of eggs,and earlier production of eggs means more clutches in the season and higher reproductive success.
Prey Discrimination Mechanisms of Chinese Crocodile Lizard (Shinisaurus crocodilurus)

蒋 洁,武正军,于 海,黄乘明,王振兴
动物学研究 , 2009,
Abstract: 鳄蜥(Shinisaurus crocodilurus)食物识别机制的研究,对进一步了解鳄蜥的捕食行为和生态学习性有重要意义。使用棉棒分别沾上去离子水、香水、黄粉虫(Tenebriomolitor L.)和蚯蚓(Pheretima sp.)的气味(蚯蚓和黄粉虫处死后绞碎以便于棉花棒蘸上),观察11只鳄蜥对4种化学刺激的反应,每个个体对每种刺激均进行24次实验重复。实验结果显示:鳄蜥对4种刺激均有反应,对黄粉虫和蚯蚓刺激的舔舌次数显著高于香水和去离子水的舔舌次数(Wilcoxon test,所有P<0.001),表明鳄蜥能检测以及识别控制刺激和食物刺激。再又对鳄蜥进行4种处理实验:(A)空白对照;(B)蚯蚓气味;(C)密封着的活蚯蚓;(D)活蚯蚓。每个个体每种处理均进行5次实验。结果显示:鳄蜥在不同处理下的行为持续时间、探究频次和攻击频次有显著差异(Friedman test,所有P<0.001)。鳄蜥在仅有视觉刺激出现的处理C以及既有化学刺激又有视觉刺激的处理D比仅有化学刺激的处理B在持续时间、探究频次和攻击频次上显著要高(所有P<0.001)。在无视觉刺激的条件下,鳄蜥在处理B的行为持续时间以及探究频次均显著高于处理A 的(所有P<0.001);而在视觉信息相同的条件下,鳄蜥在处理D中仅行为持续时间显著高于处理C(Z=3.95, P<0.001),而探究频次以及攻击频次无显著差异(前者Z=1.53, P=0.13;后者Z=1.10, P=0.27)。结果表明鳄蜥主要利用视觉捕食,化学感觉有辅助作用。鳄蜥这种食物识别机制可能与捕食模式和种系发生有关,也可能受食物的影响。
Embryonic growth and mobilization of material and energy in oviposited eggs of the white-striped grass lizards Takydromus wolteri
白条草蜥(Takydromus wolteri)胚胎生长及物质和能量的动用

XU Xue-Feng,WU Yi-Lian,OU Yong-Yue,WU Lin-Sheng,

生态学报 , 2008,
Abstract: 研究白条草蜥卵在温、湿度分别为30℃、-12kPa的条件下,孵化过程中胚胎生长以及对物质和能量的动用。孵化过程中,每隔5d测定卵重。孵化第10、15、20天,分别解剖来自不同窝的卵15、15、12枚,分离为胚胎、卵黄和卵壳。初生幼体测量、称再后冰冻处死,随后解剖分离为躯干、剩余卵黄和腹脂肪体。所有材料65℃恒温干燥,用索氏脂肪提取仪测定脂肪含量,氧弹式热量计测定能量含量,马福炉测定无机物含量。白条草蜥卵的平均孵化期为24.7d。卵孵化时从基质中吸水导致重量增加。卵孵化0—15d、15~20d、20~24.7d,胚胎分别利用新生卵能量的11%、14%和75%。0—20d,胚胎生长缓慢;20d后生长迅速。卵孵化过程中,干重、非极性脂肪和能量的转化率分别为50.3%、24.9%和51.9%。初生幼体的能量组分为:躯干95.2%,脂肪2.2%,剩余卵黄2.6%。胚胎发育所需要的无机物来自卵黄和卵壳。结果显示,白条草蜥从卵到孵出幼体物质和能量较低的转化率主要与较高胚胎发育投资和较小的剩余卵黄有关。
Water and Energy Content Variation of the Major Energy R eserves in Adult Grass Lizards,Takydromus septentrionalis

XU Xue-feng,WU Yi-lian,OU Yong-yue,

动物学研究 , 2002,
Abstract: The variation of water and energy contents in the Major Energy Reserves were studied in adult grass lizards (Takydromus septentrionalis) from March to September,2000,which collected month by month from Langyashan Mountain,Chuzhou,Anhui,Eastern China.Males and females differed in water contents of tail-free carcass and liver.There were significant monthly changes in water contents and energy contents of tail-free carcass,tail and liver in both males and females.Significant monthly changes in energy contents of fat bodies were also found in both sexes.Energy contents of tail-free carcass (including lean tail-free carcass),tail (including lean tail) were all higher in males than in females,but those of liver lower in males than in females.The results indicated that seasonal variation in the major energy reserves were correlated with the reproduction and winter hibernation.
The influence of incubation temperature on size, morphology, and locomotor performance of hatchling grass lizards (Takydromus wolteri)

PAN Zhi-Chong,

生态学报 , 2001,
Abstract: 实验用白条草蜥(Takydrous wolteri)卵由1999年和2000年4月捕自安徽滁州的19条成年雌体产出。用4个恒定温度(24-33℃)孵化白条草蜥卵,检测孵化温度对孵出幼体大小、形态和运动表现的影响。孵化卵从环境中吸不导致生量增加,卵重量增加与卵初始重量和孵化温度有关。24、27、30和33℃孵化期的平均值分别为41.9、30.6、6.25和22.6d。温度显著影响孵化成功率及孵出幼体的湿重、躯干干重和剩余卵黄干重,但对孵出幼体的性别、体长、尾长和干重无显著影响。24℃和27℃孵出幼体湿重和躯干干重大于33℃孵出幼体,剩余卵黄干则小于33℃孵出幼体;30℃和33℃孵出幼体的湿重、躯干干重和剩余卵黄干重无显著差异。孵化温度显著影响孵出幼体一些局部形态特征:24℃和27℃孵出幼体头长和头宽矫正值显著大于高温(33℃)孵出幼体,24℃孵出幼体耳径正值一般小于较高温度孵出的幼体。疾跑速与幼体体长成正相关,与幼体尾长和状态无关。高温孵出幼体运动能力较差。雄笥幼体腹鳞行数少于雌性幼体,尾长和后肢长大于雌性幼体,这些特征的两性差异与孵化温度无关。孵化热环境能诱导白条草蜥部分表型特征的变异,这些特征的变异可能对个体的适应性具有长期的影响。
Summer Habitat Characteristics of the Chinese Crocodile Lizard (Shinisaurus crocodilurus) in the Luokeng Nature Reserve, Guangdong

NING Jia-jia,HUANG Cheng-ming,YU Hai,DAI Dong-liang,WU Zheng-jun,ZHONG Yi-ming,

动物学研究 , 2006,
Abstract: 2005年6—8月,在广东省罗坑自然保护区对36处鳄蜥的生境特征进行了研究。采用样线调查法,在保护区内鳄蜥分布区随机选取了30条溪沟进行调查,对每处有鳄蜥分布的生境测量了15个相关的生态因子。通过主成分分析发现,回水塘长度和宽度、水源距离、水流速度、栖枝高度、栖枝直径、干扰距离、植被类型、植被盖度等9个生态因子对鳄蜥的生境选择有显著影响,而回水塘底质组成、回水塘水深、栖枝枯活状况、栖枝角度、溪沟类型和溪沟坡向6个生态因子的影响不显著。鳄蜥偏好的生境可归结为回水塘长度、宽度中等(均为1.0—2.0m),有位于水源正上方的栖枝,水流速度缓慢,栖枝高度0.5—1.0m、栖枝直径≤1.00cm,干扰距离>500m,植被类型为常绿阔叶林、植被盖度>60%的生境。建议提高当地居民的保护意识,重点保护水源林和溪沟两侧的植被。
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