章节大纲

  • What you will learn 
    ::你会学到什么

    • The Linnaean system of classification of living organisms
      ::活生物体的林内生物分类制度
    • What is binomial nomenclature
      ::什么是二进制术语
    • Revisions in the Linnaean system of classification
      ::Linnaean分类制度的修订

    A woman and a dog interact playfully in an outdoor setting.

    What characteristics help classify us as human?
    ::哪些特征帮助我们被归类为人类?

    Humans share many characteristics with other mammals like having body hair, mammary glands , and being warm-blooded.  However, there are quite a few characteristics that make humans different from other mammals like the ability to solve problems through complex reasoning and to use language for . 
    ::人类与其他哺乳动物有许多共同特征,比如身体毛发、哺乳腺和热血动物。 然而,有相当多的特征使得人类不同于其他哺乳动物,比如通过复杂的推理解决问题和使用语言解决问题的能力。

    Linnaean Classification
    ::林内人分类

    The on Earth over the past 4 billion years has resulted in a huge variety of . For more than 2,000 years, humans have been trying to classify the great diversity of life. The science of classifying organisms is called taxonomy . Classification is an important step in understanding the present diversity and past evolutionary on Earth.
    ::在过去40亿年中,地球上出现了各种各样的现象。2000多年来,人类一直试图对生命的丰富多样性进行分类。生物分类科学被称为分类学。分类是了解地球当前多样性和过去演化的重要一步。

    All modern classification systems have their in the Linnaean classification system. It was developed by Swedish botanist Carolus Linnaeus in the 1700s. He tried to classify all living things that were known at his time. He grouped together organisms that shared obvious physical traits, such as number of legs or shape of leaves. For his contribution, Linnaeus is known as the “father of taxonomy.” 
    ::所有现代分类系统都包含在林内亚分类系统中,它是由瑞典植物学家卡罗尔斯·林内乌斯在1700年代开发的。他试图对当时已知的所有生物进行分类。他把具有明显生理特征的生物(如腿数或叶形)集合在一起。他的贡献是,林内乌斯被称为“分类学之父 ” 。

    The Linnaean system of classification consists of a hierarchy of groupings, called taxa (singular, taxon). Taxa range from the to the species (see the Figure ). The kingdom is the largest and most inclusive grouping. It consists of organisms that share just a few basic similarities. Examples are the plant and kingdoms. The species is the smallest and most exclusive grouping. It consists of organisms that are similar enough to produce fertile offspring together. Closely related species are grouped together in a genus .
    ::Linnaean分类制度由分类分类的等级结构组成,称为分类( singulal, excon),从物种到物种的分类(见图),王国是最大和最包容的分类组,由只有几个基本相似点的有机体组成,例如植物和王国,物种是最小和最独特的分类组,由足以产生肥沃后代的类似有机体组成。密切关联的物种被组合在一个基因组中。

    Chart showing Linnaean classification with examples: human, chimpanzee, blue whale, snake.
    Linnaean Classification System: This chart shows the taxa of the Linnaean classification system. Each taxon is a subdivision of the taxon below it in the chart. For example, a species is a subdivision of a genus.

    Check your understanding!
    ::检查你的理解!

    DID YOU KNOW?
    Platypus, an animal that belongs to the order Monotremata, is unique in having characteristics of both and mammals. Like birds, it has webbed feet, a beak instead of mouth, and it lays eggs . Like mammals, it has body hair and produces milk to suckle its young. Scientists classify it as a mammal because most of its anatomical features are closer to mammals than birds.
     

    Binomial Nomenclature
    ::二进制名词

    Perhaps the single greatest contribution Linnaeus made to science was his method of naming species. This method, called binomial nomenclature , gives each species a unique, two-word Latin name consisting of the genus name and the species name. An example is Homo sapiens , the two-word Latin name for humans. It literally means “wise human.” This is a reference to our big brains.
    ::也许林内乌斯对科学的最大贡献 是他命名物种的方法。这个方法叫做二元论术语,给每个物种一个独特的、两字的拉丁名,由基因名称和物种名称组成。一个例子是人的两个拉丁名“智人人 ” 。这实际上意味着“智人 ” 。 这是对我们大大脑的提法。

    Why is having two names so important? It is similar to people having a first and a last name. You may know several people with the first name Michael, but adding Michael’s last name usually pins down exactly whom you mean. In the same way, having two names uniquely identifies a species.
    ::为什么有两个名字如此重要? 它与拥有第一个和一个姓氏的人相似。 你可能认识几个名字叫迈克尔的人,但加上迈克尔的姓通常会确定你指的是哪个人。 同样,有两个名字可以识别一个物种。

    Revisions in Linnaean Classification
    ::林内人分类的修订

    Linnaeus published his classification system in the 1700s. Since then, many new species have been discovered. The biochemistry of many organisms has also become known. Eventually, scientists realized that Linnaeus’s system of classification needed revision.
    ::林内乌斯在1700年代公布了他的分类制度。 自那时以来,发现了许多新的物种。 许多生物的生物化学也已经广为人知。 最后,科学家们意识到林内乌斯的分类制度需要修订。

    A major change to the Linnaean system was the addition of a new taxon called the . A domain is a taxon that is larger and more inclusive than the kingdom. Most biologists agree there are three domains of life on Earth: , , and Eukarya (see the Figure ). Both Bacteria and Archaea consist of single-celled . Eukarya consists of all eukaryotes , from single-celled to humans. This domain includes the Animalia (animals), Plantae (plants), (fungi), and Protista (protists) kingdoms.
    ::对林内人系统的一项重大改变是增加了一个新的分类,称为 。 域是一个比王国更大和更具包容性的分类。 大多数生物学家都认为地球上有三个生命领域: , 和 Eukarya (见图 )。 细菌和Archaea 都由单细胞组成。 Eukarya 由从单细胞到人类的所有eukaryotes组成。 这个领域包括动物(动物)、Plantae (植物)、 (fungi) 和Protista (植物) 王国。

    Phylogenetic tree illustrating the three domains of life: Bacteria, Archaea, and Eukarya.
    This phylogenetic tree is based on comparisons of ribosomal RNA base sequences among living organisms. The tree divides all organisms into three domains: Bacteria, Archaea, and Eukarya. Humans and other animals belong to the Eukarya domain. From this tree, organisms that make up the domain Eukarya appear to have shared a more recent common ancestor with Archaea than Bacteria.

     

     

    Science Friday : Isn't this Octopus Adorable?
    ::科学周五:这难道不是章鱼的崇拜吗?

    What do you call a tiny octopus with big , gelatinous skin and is cute as a button? Nobody knows quite yet! In this video by Science Friday , Stephanie Bush aims to classify and name this presently undescribed deep-sea cephalopod .
    ::如何称呼小章鱼的皮肤大而有凝胶的皮肤,又可爱又像按钮一样?谁还不知道呢?在科学周五的这段视频中,斯蒂芬妮·布什的目的是为这个目前尚未被描述的深海头目分类和命名。

     

     

     

    Summary
    ::摘要

    • Classification is an important step in understanding life on Earth.
      ::分类是了解地球上生命的一个重要步骤。
    • All modern classification systems have their roots in the Linnaean classification system.
      ::所有现代分类制度都根植于林内亚分类制度。
    • The Linnaean system is based on similarities in obvious physical traits. It consists of a hierarchy of taxa, from the kingdom to the species.
      ::Linnaean系统基于明显的物理特征的相似性,由从王国到物种的分类分类结构构成。
    • Each species is given a unique two-word Latin name.
      ::每个物种都有一个独特的拉丁字母二字名。
    • The recently added domain is a larger and more inclusive taxon than the kingdom.
      ::最近增加的域名比王国要大,更具包容性。

    Review
    ::回顾

    1. What is taxonomy?
      ::什么是分类学?
    2. Define taxon and give an example.
      ::定义分类并举一个例子。
    3. What is binomial nomenclature? Why is it important?
      ::二进制术语是什么?为什么重要?
    4. What is a domain? What are the three domains of life on Earth?
      ::什么是领域?地球生命的三个领域是什么?
    5. Create a taxonomy, modeled on the Linnaean classification system, for a set of common objects, such as motor vehicles, tools, or office supplies. Identify the groupings that correspond to the different taxa in the Linnaean system.
      ::建立以林内人分类制度为模型的分类系统,用于一套通用物体,如机动车辆、工具或办公用品。 确定与林内人系统中不同分类组相对应的组别。