秃鹫骨骼的解剖学特点

对秃鹫(aegypius monachus)骨骼进行了详细的观察、描述和功能分析.结果表明,其头骨较宽;上喙粗长、前端近垂直下弯;前额骨游离,眶突发达;龙骨突不发达;叉骨呈\"U\"形,叉骨头膨大、具发达的叉骨,乌喙骨关节面;前肢骨明显长于后肢骨;第一掌骨伸肌突发达;跗跖骨前后宽扁,跗后跟嵴短;足部近端趾节略长于远端趾节.这些特征与秃鹫的取食方法与偏好及飞行与栖息特点密切相关.     

褐马鸡的骨骼解剖

褐马鸡的骨骼解剖温江,娄凤玲,刘冰（山西师范大学生物系,临汾０４１００４）褐马鸡和大熊猫、一样被列为我国的一级保护动物,它是我国特有的珍稀濒危鸟类。本文研究的主要内容为褐马鸡的骨骼系统。褐马鸡的骨骼系统,依着生部位分为躯干骨骼、附肢骨骼及带骨、颅骨。...     

鸵鸟骨骼的解剖

鸵鸟骨骼的解剖彭克美邱德新汪定基周和清罗旋（华中农业大学畜牧兽医学院武汉４３００７０）关键词驼鸟骨骼解剖于１９９６年３－４月,采用大体解剖学方法,对２例成年非洲驼鸟（Ｓｔｕｒｔｈｉｏｃａｍｅｌｕｓ）骨骼进行了系统的解剖。观察到以下一些明显的特点。非...     

羚牛骨骼解剖补遗

羚牛Budorcas taxicolor是我国一类保护的珍稀动物,吴家炎等(1990)对羚牛的骨骼进行了解剖,认为羚牛腓骨只保留近端,骨远端体消失,近端即腓骨头与胫骨外髁愈合,远端形     

上海动物园圈养斑嘴环企鹅种群统计学与遗传学分析

根据1984—2017年上海动物园圈养斑嘴环企鹅Spheniscus demersus数据,应用Sparks 1.6和PMx 1.0进行数据整理、统计学和遗传学分析。结果显示,该种群数量呈增长状态,但也存在如下问题:(1)种群中未知性别比例过高,占46.25%;(2)种群年龄结构不合理,0~4岁及7~8岁个体数量不足,育龄个体中未知性别的数量较多;(3)雌雄个体0~1岁、10~13岁的死亡率偏高,曲霉菌病是致死的主要原因;(4)参与繁殖的奠基者数量(9只)和潜在奠基者数量(1只)少,分属2个家系,且后代数和贡献值明显不均衡,种群的平均亲缘关系值为0.097 2,种群的平均近亲繁殖系数为0.099 5,存在近亲繁殖现象;(5)虽然现有种群保留了野生个体90.28%的基因多样性,但未来丢失也较快。因此,为了建立健康的斑嘴环企鹅种群,应尽快引进新的血统,开展性别鉴定工作,采取预防为主、防治结合的方式降低曲霉菌病的致病率;采用各种技术如人工授精技术提高企鹅受精率,为繁殖个体,尤其是后代数量过少的奠基者个体提供均等的繁殖机会,从而加强上海动物园圈养斑嘴环企鹅的种群管理。     

冠斑犀鸟的骨骼系统解剖

对冠斑犀鸟的骨骼系统进行了详细的观察和描述,其头骨厚重、骨壁坚硬;颌骨、前颌骨极度前伸,构成巨大的上喙,其后部连同鼻骨向背方显著隆起,构成盔.寰椎、枢椎、尾综骨、胸骨等形态特殊.跗跖骨结构以及足趾近、远端趾节的长度反映了明显的树栖性特征.     

中国水蛇骨骼系统解剖

本文报道了中国水蛇骨骼系统的大全解剖,并叙述了脑颅各骨之内面观。     

太行隆肛蛙骨骼系统的解剖

对太行隆肛蛙的骨骼系统进行了详细的观察和描述:鼻骨较大,蝶筛骨在背而部分显露,额顶骨前后几等宽,前耳骨大.舌骨体宽明显大于长.上胸软骨小于剑胸软骨,肩胸骨基部不分叉,与中胸骨几等长,剑胸软骨呈扇形状,后端有缺刻.第8椎体为舣凹型椎体,肩带固胸型.     

红颊骨骼的解剖研究

红颊骨骼的解剖研究ＡＮＡＴＯＭＩＣＳＴＵＤＩＥＳＯＮＴＨＥＳＫＥＬＥＴＯＮＳＹＳＴＥＭＯＦＨＥＲＰＥＳＴＥＳＡＵＲＯＰＵＮＣＴＡＴＵＳ红颊（Ｈｅｒｐｅｓｔｅｓａｕｒｏｐｕｎｃｔａｔｕｓ）是一种具有较高经济价值的小型哺乳动物,研究其骨骼的解剖结构...     

Female-solicited extrapair matings in Humboldt penguins fail to produce extrapair fertilizations

The study reported in this paper demonstrated that Humboldtpenguins atPunta San Juan, Peru, despite forming pair-bonds,are not strictly monogamousin their mating behavior: 19.2%of the study males and 30.7% of the studyfemales (21 nests)engaged in extrapair copulations. The total number ofcompletedmatings observed during the course of this study was 106, ofwhich17.9% were extrapair copulations. Using DNA fingerprintingwe demonstratedthat none of these extrapair copulations resultedin extrapair fertilizations;all 49 offspring were attributedto the putative father. Location ofcopulations suggested thatfemales solicited these extrapair copulationsbecause 89.2%of Humboldt penguin within-pair copulations occurred at thehomeburrow, yet extrapair copulations took place at a differentlocation based onthe sex of the penguin. Extrapair copulationsby males occurred at their nest,whereas females conducted 92%of their extrapair copulations away from thenest. These resultsare most consistent with mate-appraisal and epiphenomenalhypotheses.     

Seasonal variations in the behavioural thermoregulation of roosting Humboldt penguins ( Spheniscus humboldti) in north-central Chile

We examined the thermoregulatory behaviour (TRB) of roosting Humboldt penguins (Spheniscus humboldti) in north central Chile during summer and winter, when ambient temperatures (T_a) are most extreme. Each body posture was considered to represent a particular TRB, which was ranked in a sequence that reflected different degrees of thermal load and was assigned an arbitrary thermoregulatory score. During summer, birds exhibited eight different TRBs, mainly oriented to heat dissipation, and experienced a wide range of T_a (from 14 to 31°C), occasionally above their thermoneutral zone (TNZ, from 2 to 30°C), this being evident by observations of extreme thermoregulatory responses such as panting. In winter, birds exhibited only three TRBs, mainly oriented to heat retention, and experienced a smaller range of T_a (from 11 to 18°C), always within the TNZ, even at night. The components of behavioural responses increased directly with the heat load which explains the broader behavioural repertoire observed in summer. Since penguins are primarily adapted in morphology and physiology to cope with low water temperatures, our results suggest that behavioural thermoregulation may be important in the maintenance of the thermal balance in Humboldt penguins while on land.     

Agonistic behavior in wild male Magellanic penguins: when and how do they interact?

Game-theory models predict that the frequency and type of agonistic interactions should vary with the value of the resource being contested. We describe bill duels and overt fighting in male Magellanic penguins (Spheniscus magellanicus) at a breeding colony and determine whether these behaviors change with the value of the nests over which they interact. Bill duels represent low levels of aggression while overt fighting high levels of aggression. Consistent with predictions, overt fighting was more common before egg laying when nests have the highest potential value while bill duels were more common at failed nests later in the season when nests are less valuable as they could not be used for reproduction until the next season. Contrary to expectations, overt fights were shorter and resulted in fewer cuts before egg laying than after egg laying. Large size asymmetries between opponents before egg laying may enable losers to quickly assess their opponents and leave before they are hurt. As predicted, the duration and damage occurring during overt fights were positively correlated with nest cover, which is correlated with higher reproductive success. We conclude that male Magellanic penguins have rules of engagement that in the most cases follow game-theory predictions on when and how to interact.     

形目鱼类连体胚胎两例

报道了鳉形目鱼类食蚊鱼(Gambusia affinis)和青鳉(Oryzias latipes)的连体胚胎现象各一例.上述连体胚胎均为腹部粘连,内脏各器官分别独立,产出或孵化后短时存活.     

The identification of polypeptides synthesised during the acquisition of teichoic acid synthetic activity in Bacillus licheniformis

An attempt has been made to identify proteins synthesised during induction of teichoic acid synthesis in Bacillus licheniformis ATCC 9945. The proteins are recognised as those produced on the change from teichuronic acid to teichoic acid synthesis that occurs after the transfer of the bacteria from phosphate-limited to phosphate-rich conditions. B. licheniformis was grown in phosphate-limiting conditions in the presence of threonine to stimulate threonine uptake. The bacteria were then transferred to phosphate-rich conditions and were pulsed-labelled with [¹⁴C]threonine during the change to teichoic acid synthesis. All of the proteins were extracted from the cells with sodium dodecyl sulphate and were examined by sodium dodecyl sulphate-polyacrylamide gel electrophoresis. Radioactive polypeptides were identified by fluorography of the polyacrylamide gels. The radioactive polypeptides that were formed on change from teichuronic acid to teichoic acid synthesis were compared with the polypeptides present in a membrane sub-fraction that had high teichoic acid-synthesising activity. The labelling of nine polypeptides with [¹⁴C]threonine was dependent on new RNA synthesis. Of these nine polypeptides, five were also present in the membrane sub-fraction with the highest teichoic acid-synthesising activity.     

Leaf micromorphology inAgathis and its taxonomic implications

This study surveys the micromorphological surface structure of the leaves of the conifer genusAgathis (Araucariaceae) from throughout the range of the genus (Malaysia to New Zealand and Fiji) as seen with the scanning electron microscope. These data confirm that the vegetative parts ofAgathis are taxonomically highly conservative, but suggest the Melanesian and New Zealand elements to be distinctive from those of the rest of the genus, and from one another. Conclusions are compared with those that have been derived from studies based on other characters.     

Drag Reduction in a Swimming Humboldt Penguin, Spheniscus Humboldti, when the Boundary Layer is Turbulent

An area of protruding feathers found around the beak of many penguin species is thought to induce a turbulent boundary layer whilst swimming. Hydrodynamic tests on a model Humboldt penguin, Spheniscus humboldti, suggest that induced turbulence causes a significant reduction in boundary layer height, flow separation, and an average of 31% reduction in drag ( 1.0 m/s to 4.5 m/s). Visualisation of surface flow showed it to follow the body profile, over the feet and tail, before separating. Movement of the feet in swimming penguins correlates with steering of the bird. Induced turbulence may therefore further increase swimming efficiency by reducing the amount of foot movement required to direct the swimming bird.