大陆漂移假说与陆地脊椎动物的地理分布

地球从形成至今已有 4 5亿年的历史了 ,原始脊椎动物始现于 5亿多年前。伴随着动物由低等向高等的进化、辐射和发展 ,地球上各陆块也经历了几度的离与合 ,陆块位置的相对变化进而影响了动物在地球上的分布。通常认为 ,地球物理的历史变迁是形成现今脊椎动物分布格局的主要因素。对于如何合理解释现今世界上各大洲、大洋的形成和大陆动物区系的差异 ,有不同的学说 ,其中大陆漂移假说普遍为人们所接受。该假说是在 1 91 2年由德国地球物理学家魏格纳提出的 ,他根据美洲大陆与非洲大陆的海岸线几乎可以互补吻合这一事实 ,结合其它方面的证据 ,…     

《两栖纲》一节教学设计

两栖动物在脊椎动物进化史上占有重要地位，是脊椎动物由水生向陆生过渡的一个类群。两栖动物既保留了水栖祖先的许多特征，有获得了一系列陆栖脊椎动物的特点，因而学生了解两栖动物的特征，能使学生更好的理解和掌握脊椎动物的进化历程。根据生物学大纲和学生知识的现状，针对教材的特点，利用学生对动物的喜爱与探索的心理特征制定了本节目标：     

四种实验动物血液有形成分比较研究

对鲤鱼、花背蟾蜍、家鸡、家兔 4种实验动物的血细胞形态进行了显微观察并对其血细胞数量、红细胞、血小板大小进行了测量 .结果表明 :随着脊椎动物由低等向高等的进化 ,红细胞的形态由长椭圆形、椭圆盘形、双凹椭圆形到双凹圆盘形 ,细胞的数量由少增多 ,细胞体积由大变小 ,由有核到无核 ,细胞分化程度愈高 ;白细胞的种类和血小板的数量增多 ;血红蛋白含量呈上升趋势 .鱼类与陆生脊椎动物变化趋势不同 ,血红蛋白相对较高 .血液有形成分的这些变化与动物的进化和生活环境密切相关     

鱼鳍的特殊形状和功能

鳍是鱼和其他水生脊椎动物适应水中生活的运动器官。就鱼鳍而言一般由皮肤、柔软的鳍条和坚硬不分节的鳍棘构成;由于着生部位不同有背鳍、臀鳍、尾鳍、胸鳍和腹鳍之分;其中前三种都不成对,称为“奇鳍”,后两种与其他脊椎动物的前后肢一般是成对的,称为“偶鳍”。但是,随着生活环境、生活习性的不同,在长期的进化过程中某些鱼鳍功能和形状发生了改变,甚至有些鳍退化或消失。现将各种鱼鳍简介如下。     

脊椎动物的皮肤衍生物

脊椎动物的皮肤由表皮和真皮构成,覆盖在整个体表和所有孔道的表面。皮肤衍生物是指脊椎动物在长期的进化过程中,由皮肤演变形成的一种适应各自生存环境的特殊结构。皮肤衍生物的种类很多,按其来源不同,可分为以下3类:     

何谓“趋同进化、趋异进化、协同进化”

1.趋同进化"趋同"即殊途同归的意思.它是指亲缘关系较远的生物,由于生活环境、生活方式相似而在长期的适应过程中所形成的体形或器官等异常相似的现象.它是不同生物在相同环境条件下得到相同选择的结果.例如,空中的鸟类与蝙蝠,海中的鲨鱼与鲸鱼,它们的体形都表现出明显的相似,但在亲缘关系上却分别隶属于不同的纲.又例如,仙人掌科和大戟科是截然不同的种子植物,但沙漠中的一些大戟科植物和仙人掌的外形都很相似,也有多水的肉质茎.环节动物的眼和节肢动物的眼迥然不同,但和脊椎动物的眼却很相似,而环节动物和脊椎动物的亲缘关系却很远,这些都是趋同进化.但详细检查环节动物的眼,发现它们的眼没有虹膜,晶体没有调节能力,视网膜也与脊椎动物眼的视网膜不同,因此它们的眼与脊椎动物的眼并不是同源的,只是在自然选择下分化出来的同功器官.     

动物身体大小与进化

动物身体的大小与进化有什么关系呢?生物学家与工程技术人员共同研讨,提出了这样的回答:“节肢动物的进化伴随着身体的减小,脊椎动物的进化总是导致身体体积的增大”。古生物学家证明,在寒武纪、志留纪和泥盆纪生活的巨大的大甲目(Gigantostra-ca),长达两米,而它们的后代——今天的蜘蛛纲却比较小,特别是蜱螨类身体仅几毫米。     

中外科学家成功绘制达尔文勇地雀基因组图谱

据2012年8月26日《科技日报》报道,"万种脊椎动物基因组计划"(G10K)联盟和华大基因近日联合宣布,勇地雀基因组图谱绘制完成。这是双方合作完成的首个可在UCSC基因组数据库中获取的脊椎动物基因组。本研究将有助于对生活在同一岛屿上的具有丰富遗传多样性的近缘物种基因组研究,也有助于阐明它们的的遗传学和性状进化机制。     

浅谈两栖类动物由水生到陆生的适应与不适应

生物界与宇宙中的一切其它事物一样,是在不断地运动不断地发展着的。在悠久的地球历史时期里,生物的发展,从少数简单、原始的单细胞生物开始,经历了漫长曲折的道路,最后进化到今天在地球上滋生繁殖的大约将近200万种植物、动物及其我门人类。在生物进化过程中,由水生到陆生是具有划时代意义的,而两栖类则是由水生到陆生的过渡类型。其幼体在水中生活,用鳃呼吸,发育要经过变态,在陆地上生活,用肺来呼吸。两栖类是最先登陆的脊椎动物,     

始祖鸟化石疑案

保存在英国自然博物馆的始祖鸟化石,在动物进化史上是异常珍贵的化石.从始祖鸟化石的骨骼构造看,是爬行动物;从它的羽毛痕迹看,又是一种古代鸟类.它不仅是爬行类向鸟类进化的一个实证,而且代表了脊椎动物由陆地向空中发展成功的标志,说明现代鸟类均起源于始祖鸟.     

The Influence of Perceived Disgust on Students’ Motivation and Achievement

There are a wide range of student emotions in academic settings, but apart from emotions such as interest and well-being, disgust is a negative emotion which might be relevant in biology education, for instance, during dissection or when encountering living animals. This paper addresses the issue of situational disgust during a course at the university using living animals and prepared mounts. The course covers a wide range of organisms from protists (e.g. Paramecium) through invertebrates to vertebrates and uses many methods (e.g. microscopy, dissection, and behavioral observations) and specific content (anatomy, structure, and behavior). The dissection of the trout was rated as most disgusting, followed by working with living woodlice, living earthworms, and living snails. The least disgusting lessons were those dealing with microscopy, mammalian skulls, honeybee dance, and bird flight. Based on animals, macro-invertebrates were rated as most disgusting and mammals as least disgusting. Concerning methods, observing through a microscope was perceived as being least disgusting, followed by experiments without animals, then followed by experiments with living animals and, most disgusting, dissection. Disgust was correlated negatively with interest, well-being, and competence but positively with pressure and boredom. Thus, low disgust is related to high interest, well-being, and competence, while higher disgust is related to higher pressure and boredom. The results show a need for measuring situational disgust in addition to survey studies. They also suggest that perceived disgust negatively affects intrinsic motivation. This has implications for biology teaching, because carrying out dissections or experiencing living animals in the classroom may have a detrimental effect on motivation.     

Life: Complexity and diversity

With rare exceptions, each sexually reproduced individual is endowed with a distinctive genetic constitution. Nevertheless living organisms share many genes, the greatest level of sharing characterizing those belonging to the same species. The total number of such species is unknown, but probably exceeds ten million, the vast majority of them being small invertebrate animals.     

Preschoolers' Ability to Distinguish Living Kinds as a Function of Regrowth

In order to acquire a theory of biology, children must acquire knowledge about living kinds. Although many studies have shown that preschool children do not accurately classify living kinds and do not use appropriate properties when asked to decide whether something is a living kind, recent work has shown that 3- and 4-year-olds do know something about biological growth. The ability of kinds to heal through regrowth was used in this paper as a measure of children's implicit understanding that plants and animals can be grouped together. In 3 experiments, children were told that animals, plants, and artifacts had been damaged and were asked whether the objects could heal through regorwth and whether a person could mend them. In all studies, children were sensitive to ontological kind, 4-year-olds realized that both plants and animals can regrow but that artifacts must be fixed by human intervention. 3-year-olds were less knowledgeable but did realize that artifacts cannot regrow. Overall, children showed some biological knowledge, implicity grouping plants and animals together and differentiating them from artifacts.     

南极大陆在动物地理区划中的位置

分析了南极大陆地史变迁 ,地理环境和动物组成及特点 ,本文认为南极大陆动物地理生态区系划分中应与其它六个地理界分开 ,把南极大陆划分成一个新的单独的动物地理区 (界 ) .     

Lessons with Living Harvest Mice: An empirical study of their effects on intrinsic motivation and knowledge acquisition

The aim of this study was to evaluate the effects of living animals on pupils’ intrinsic motivation and knowledge. Various studies from the late 1970s and 1980s stress the high effectiveness of authentic learning experiences in pupils’ knowledge acquisition. However, there are only few current empirical studies on this topic. The research question of our study is to assess whether the use of living animals in the biology classroom supports intrinsic motivation and knowledge acquisition. In a pre-/post-test design, 185 fifth graders received two different treatments: the experimental group (N?=?74) was taught with living harvest mice (Micromys minutus) and the control group (N?=?111) received lessons with the same content which was presented in short film clips on laptop computers. Knowledge acquisition was assessed with open-ended and closed questions, while intrinsic motivation was tested with an adapted version of the Intrinsic Motivation Inventory (IMI). There were no differences in knowledge acquisition between the treatments. However, the results of the IMI showed significant differences in favour of the experimental group in interest/enjoyment, perceived competence, and perceived autonomy. Thus, living animals exert a positive influence on motivation.     

废旧干电池对泥鳅的毒性效应

以抗污染能力强的泥鳅(Misgurnus anguillicadatus)为实验材料,研究了废旧干电池污染的水源对水生生物具有极强的毒害作用.结果表明,泥鳅受毒害程度与水体中废旧干电池的数量和暴露时间成正相关关系;对受毒害但未死亡的个体断尾取血,显微镜下观察血红细胞的形态、结构,发现在废旧干电池污染的水体中残存的个体,其血红细胞的变异率远远超过生活在正常水体中的个体.     

白马人山、树和动物崇拜的文化人类解读

山、树和动物崇拜是白马民间信仰的重要内容,在白马人精神世界占有重要地位。极为不利于农业生产的生存环境加剧了白马人对山、树和动物等生存资源的依赖,而正是这一依赖孕育了白马人山、树和动物崇拜意识。虽然,在白马人的山、树和动物崇拜的具体实践中从未提及＂环境意识＂这一概念,但它所蕴含的丰富的生态思想客观上具有保护生态环境的重要作用。     

Defense signaling in plants

Self defense is the basic response of every living organism. This response is readily observed in animals because of their physical movements typically involved in that process. Being immobile, plants have evolved highly complex defense mechanisms that differ from those commonly seen in animals. Plants are able to use chemicals of various kinds as their weapons against enemies.     

安阳市野生动物特种养殖业现状及发展对策

随着人类生活水平提高,对野生动物需求量越来越大,驯养繁殖与经营利用野生动物的前景日益广阔,重点就现状与发展对策两大方面加以详细阐述,介绍了安阳市野生动物特种养殖业的现状和发展对策,其中发展对策又从4个方面作了详尽阐述,力求推动野生动物特种养殖业的发展,开创野生动物特种养殖业的新局面。