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  • 人类和昆虫 -- -- 高级

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    What snack do you have after school?
    ::你放学后吃什么小吃?

    Maybe not these silkworms, but, to many people, these skewered silkworms are considered a delicacy. The consumption of feeds millions or billions of people. Popular bugs to eat include beetles, butterflies and moths, bees and wasps, ants, grasshoppers, crickets and locusts, and stinkbugs.
    ::也许不是这些丝虫,但对于许多人来说,这些被割开的丝虫被认为是一种美味。 食用成百上千万或数十亿人的食用。 常见的食用虫虫包括甲虫、蝴蝶和飞蛾、蜜蜂和黄蜂、蚂蚁、、板球和蝗虫以及臭虫。

    Humans and Insects
    ::人类和昆虫

    Most humans interact with insects on a daily basis. In addition to encountering insects outside, many insects live in your homes with you. Most human-insect interactions are benign, that is, no one gets hurt. Some are really just a nuisance; being bit by a mosquito or hearing a fly buzzing around your room can be quite irritating. However, there are other interactions between humans and insects that are enormously devastating, and there are also some that are extremely beneficial. We will consider the relationships of humans and insects in this section.
    ::大部分人每天都与昆虫发生互动。除了在外面遇到昆虫之外,许多昆虫也与你住在一起。大多数人类昆虫的相互作用是良性的,也就是说,没有人会受到伤害。有些只是烦恼;被蚊子咬或听到在你房间周围的苍蝇嗡嗡声会很烦恼。然而,人类和昆虫之间还有其他的相互作用具有极大的破坏性,还有一些是极为有益的。我们将在本节中考虑人类和昆虫之间的关系。

    Insects and Crops
    ::昆虫和作物

    Other than the ants that may try to invade your picnic lunch, you have probably never considered insects to be major competitors for your food sources. In fact, insects are considerable competitors for human food sources, particularly crop plants. It takes a lot of plant material to feed the herbivorous insects that make up roughly half of all insect . The fight to protect agricultural crops from destruction by insects is an ongoing battle for humans. Sometimes insects can impart sudden and devastating damage to plant resources. An example of this occurred as recently as 2004 when swarms of locusts caused over $2.5 billion worth of crop damage to over 20 countries in West and North Africa. The threat of these swarms continues today in many regions of Africa and Asia. The desert locust is shown in  Figure .
    ::除了可能试图侵入你的野餐的蚂蚁之外,你可能从未认为昆虫是食物来源的主要竞争对手。事实上,昆虫是人类食物来源,特别是作物植物的大量竞争对手。需要大量植物材料来喂养占昆虫总数约一半的食草昆虫。保护农作物不受昆虫破坏的斗争是一场针对人类的持续战斗。昆虫有时会给植物资源造成突然和毁灭性的损害。这方面的一个例子发生在2004年,当时蝗虫群对西非和北非20多个国家造成了价值超过25亿美元的作物损害。今天,这些蝗虫的威胁在非洲和亚洲许多地区继续存在。沙漠蝗虫在图中显示。

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    A desert locust. The desert locust actually has two different adult life forms. The solitary life form is not harmful to human crops, but the gregarious form congregates in extremely large swarms as a result of changes in the hormonal signals that they emit. These swarms fly over long distances and feed voraciously on both crop and non-crop plants.
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    A Locust Swarm. A swarm of locusts in the African country of Mauritania darkens the mid-day sky. The hungry insects will eat virtually all the plants in their path.

    Insecticides are one possible solution to the problem of some crop-damaging insects, but there are a number of serious problems with this approach. One is the potential toxicity of these compounds, which harms both the farm workers who are exposed to large quantities and the consumers who eat plant material that may have traces of insecticide on them. Another problem with insecticides is that insects often reproduce rapidly enough to evolve pesticide resistance fairly quickly. Instead of this method, many other methods of insect pest control, which are more environmentally sound, can be used. These include crop rotation, the introduction of natural predators of the offending insects, and breeding to select for plants that are resistant to certain insect infestations.
    ::杀虫剂是解决某些作物退化的昆虫问题的一种可能办法,但这种办法存在若干严重问题,其中之一是这些化合物的潜在毒性,它既伤害接触大量杀虫剂的农业工人,又伤害食用可能含有杀虫剂痕迹的植物材料的消费者;杀虫剂的另一个问题在于昆虫的繁殖速度往往足够快,足以相当迅速地演变成对杀虫剂的抗药性;不采用这种方法,可以使用其他许多更环保的虫害控制方法,其中包括作物轮作、引进自然捕食害虫的昆虫,以及种菜选择耐某些虫害的植物。

    The other side of this issue is that most flowering plants, including many that are components of agricultural crops, are critically dependent on insects to mediate their through pollination . Therefore, we are critically dependent on insects for our survival. Flowering plants make up a large fraction of the primary on Earth. Primary producers harvest the energy of the sun and turn it into an energy source that the rest of the organisms on the planet, including ourselves, need in order to survive. Even if you obtain a lot of your nutrition from meat sources, those (cows, pigs, and chicken) gained all of their nutrition from the plants they ate.
    ::这个问题的另一方面是,大多数开花植物,包括许多作为农作物组成部分的植物,都严重依赖昆虫通过授粉进行调节。因此,我们的生存严重依赖昆虫。花生植物占地球上初级植物的很大一部分。初级生产者收获太阳的能量,将其转化为包括我们在内的地球上其他生物体生存所需的能源来源。即使从肉类来源获得大量营养,这些植物(牛、猪和鸡)也从它们所吃的植物中获得全部营养。

    Insects and Human Disease
    ::昆虫和人类疾病

    Although the bites of insects, including poisonous species, are almost never fatal in and of themselves, insects are the cause of an extremely large number of human deaths - over one million each year. These fatal consequences are largely the result of bites from hematophagous ( eating), parasitic species that feed on human blood and act as vectors for disease transmission. Examples include the spread of the that cause bubonic plague by fleas during a number of pandemics throughout history and the continued spread of malaria by mosquitoes. Another example is the spread of the that cause sleeping sickness by tsetse flies in Africa. It is estimated that up to four million people die each year as a result of these insect-borne diseases spread by the organisms shown in Figure .
    ::虽然昆虫(包括有毒物种)的咬伤本身几乎从来不致命,但昆虫是每年有100多万人死亡的主要原因,这些致命后果主要是食用血友病的咬伤、食用人类血液的寄生虫和作为疾病传播媒介的咬伤造成的,例如,在历史上一系列流行病中,跳蚤传播流行,导致大流行,疟疾继续由蚊虫传播。另一个例子是,在非洲,采采采蝇造成睡眠疾病的蔓延。据估计,每年有400万人死于图所示生物传播的昆虫传播疾病。

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    Indirectly harmful insects. The three insects shown here, (a) a flea (microscopic image), (b) a mosquito, and (c) a tsetse fly, are not harmful in and of themselves, but by feeding on human blood they can transfer dangerous disease-causing organisms and lead to millions of infections each year, many of which are deadly.

    Stings from stinging insects, such as bees, occasionally result in human deaths (about 20 per year in the U.S.), which are not caused by the sting itself but by a severe allergic reaction to components of the insect’s venom. This reaction is called anaphylactic shock, and it requires immediate medical attention.
    ::毒刺昆虫(如蜜蜂)的毒刺有时会导致人的死亡(美国每年大约20人 ) , 这不是由毒刺本身造成的,而是昆虫毒液成分的严重过敏反应造成的。 这种反应被称为厌食性休克,需要立即医疗护理。

    Drosophila melanogaster : An Early Model Organism
    ::Droosophila melanogaster:早期示范生物体

    In the : (Advanced) concept you learned about a particular roundworm species called C. elegans that has served as a model organism in biological research. A model organism is a species that is selected by the scientific community for extensive research study. These organisms are usually selected based on their ease of use in the (inexpensive to maintain, short so many generations can be studied, etc.) and the similarity of their systems to other organisms of biological significance such as humans. The insect class includes a model organism that has made an even more significant contribution to our understanding of animal biology than C. elegans: the fruit fly Drosophila melanogaster (commonly referred to simply as drosophila ), shown in  Figure .
    ::在伤心高级)概念中,你了解了一种叫C. elegans的昆虫物种,该物种曾是生物研究中的示范生物体。一种模型生物体是科学界为广泛研究而挑选的物种。这些生物体的选取通常基于它们在图中显示的图中较易使用(维持成本低,可以研究几代人等)以及它们的系统与人类等其他具有生物意义的生物体相似。昆虫类包括一种比C. Elegans(通常简称为drosophila)对动物生物学的理解作出更重大贡献的模型生物体:果蝇Drosophila melanogaster(通常简称为drosophila)。

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    An extremely beneficial insect: Drosophila melanogaster. As a model organism for research in the fields of genetics, developmental biology, and neurobiology, this little fly has made enormous contributions to our knowledge of the biology of animals.

    Studies first began on drosophila genetics in the early 1900s, led by a scientist named Thomas Hunt Morgan in what became known as the fly room at Columbia University. Drosophila is one of the most studied organisms in biological research, and these studies have made particularly important and extensive contributions to our understanding of the and of animals. Much of this information has been readily applicable to understanding human biology. For instance, approximately 75% of known human disease genes have a related gene in the drosophila genome . Studying these genes in an organism where can be generated and their effects analyzed in a lab is an efficient way to gain an understanding of how these genes might work in humans. Just to give you some examples of the many human conditions that can be modeled in an organism as seemingly simple as a fly, drosophila is used as a model organism for:
    ::1900年代初期,首先开始对脱氧植物遗传学进行研究,研究由一位名叫Thomas Hunt Morgan的科学家在哥伦比亚大学的飞翔室中领导,Drosophilla是生物学研究中研究最多的生物体之一,这些研究为我们了解动物和动物作出了特别重要和广泛的贡献。许多这类信息很容易用于了解人类生物学。例如,大约75%已知的人类疾病基因在脱氧植物基因中具有相关的基因。研究生物体中能够产生这些基因并在实验室中分析这些基因的效果,是了解这些基因如何在人类中发挥作用的有效方法。仅举几个例子,说明在像苍蝇一样看上去简单的生物体中可以建模的许多人类条件。

    • Parkinson’s Disease.
      ::帕金森病。
    • Huntington’s Disease .
      ::亨廷顿病。
    • Alzheimer’s Disease.
      ::阿尔茨海默氏病。
    • .
    • .
    • Drug abuse (including cocaine and alcohol).
      ::药物滥用(包括可卡因和酒精)。

    One major discovery that was first found in Drosophila was a family of genes called homeobox genes. The encoded by this gene family all have a specific region called the homeodomain that can bind to and cause other genes on the to become activated. These genes have since been found in almost all animal phyla, and they are now known to be incredibly important for generating the different regions of an animal’s body such as the thorax and the abdomen (this is called patterning the body). The identity of each of these regions is important for the proper placement of limbs and other body parts. For example, a mutation in just one of the Drosophila homeobox genes can cause a leg to form on the head region in place of an antenna. This type of anomaly is rarely seen in humans and other vertebrates because mutations in homeobox genes are so detrimental that they usually lead to a miscarriage.
    ::最初在德罗索比拉发现的一个重大发现是基因家族,称为软骨箱基因。由这个基因家族编码的基因家族都有一个特定的区域,即能够连接并导致其他基因被激活的软骨体域。这些基因在几乎所有动物植物中都发现了,现在人们知道,对于产生动物身体的不同区域,例如胸腔和腹部(这被称为身体的构造)来说,这些基因是极其重要的。每个区域的身份对于正确放置肢体和其他身体部分都很重要。例如,仅仅一个Drosophilla家软体基因的突变可以在天线的顶部区域形成一条腿。这种异常现象在人类和其他脊椎动物中很少被看到,因为主脑基因中的突变非常有害,通常会导致流产。

    The study of model organisms is a powerful field of biological research, and, through the contributions of Drosophila melanogaster, insects have been a major force in this work.
    ::研究模型生物是生物学研究的一个强大领域,通过Drosophila melanogaster的贡献,昆虫一直是这项工作的主要力量。

    Forensic Entomology
    ::法医昆虫学

    An interesting use of insects by humans that you may never have thought about before is in forensic entomology. Forensic entomologists use their expertise on the life cycles and habitats of insects to help solve crimes, particularly homicides. How do insects provide information about a crime scene? The feature of insect species that is most useful to forensic entomologists is that they feed on dead vertebrates (like humans) or on other organisms that feed on dead vertebrates. By examining the life stage of insects found on a murdered body (stage of embryogenesis or larval stage) the time of death can often be determined. A difference between the species found on the body and those inhabiting the area in which the body was found can also sometimes indicate that the body was moved after death. Surprisingly, in some instances, studying the insects found on the body may also lead to the cause of death. This may be the case when the person was killed using poisons that are no longer detectable in their system. Insect larva found on the body may still contain traces of these substances.
    ::人类对昆虫的一种有趣的使用,你以前从未想过,这是在法医昆虫学中。法医昆虫学家利用其关于昆虫生命周期和栖息地的专门知识来帮助解决犯罪,特别是杀人案件。昆虫如何提供有关犯罪现场的信息?昆虫物种对法医昆虫学家最有用的特征是它们食用死脊椎动物(像人类一样)或食用死脊椎动物的其他生物。通过检查在被谋杀尸体上发现的昆虫(胚胎产生阶段或幼虫阶段)的生命阶段,往往可以确定死亡的时间。在尸体上发现的物种与在发现尸体的地区居住的物种之间的差别有时也表明尸体在死亡后被移走。奇怪的是,在某些情况下,研究在尸体上发现的昆虫也可能导致死亡的原因。在人被杀死时,使用在他们体内无法再检测到的毒药。在尸体上发现的幼虫可能仍然含有这些物质的痕迹。

    This may sound like some gruesome stuff, but for the families of victims and potential future victims of a predator, any information that can help the investigation of the crime is vital. The death may also have been accidental or caused by suicide. Either way, it is important for family and community members to find out what happened. We have both the insects themselves, who are just going about their normal business, and the dedicated scientists who are willing to do this work to thank for these contributions to the justice system.
    ::这听起来可能像一些可怕的东西,但对于受害者家属和捕食者的潜在未来受害者来说,任何有助于调查这一罪行的信息都是至关重要的。死亡也可能是意外的,也可能是自杀造成的。无论哪种方式,家庭和社区成员都有必要了解所发生的事情。我们既有昆虫本身,他们正在从事正常的生意,也有热诚的科学家,他们愿意做这项工作,感谢这些对司法系统的贡献。

    KQED: Better Bees: Super Bee and Wild Bee
    ::KQED: 更好的蜜蜂:超级蜜蜂和野蜜蜂

    Honeybees are one of the most well-known insects on the planet. Bees are naturalized on every continent except Antarctica. Honeybees have a highly developed social structure and depend on their community, or colony, for survival. Bee colonies can contain up to 20,000 bees. When bees search plants for nectar , pollen sticks to the fuzzy hairs that cover their hind legs. At the next flower , some of the pollen rubs off and fertilizes that flower. In this way, bees help improve fruit production. Bees pollinate an estimated 130 different varieties of fruits, flowers, nuts, and vegetables in the United States alone. Farmers obviously depend on bees to pollinate crops, such as fruits and nuts, but thousands of bee colonies have disappeared in recent years. This could be a devastating issue for farmers. Can anything be done? Meet two Northern California researchers looking for ways to make sure we always have bees to pollinate crops.
    ::蜜蜂是地球上最有名的昆虫之一。蜜蜂在南极洲以外的每个大洲被归化为自然体。蜜蜂拥有高度发达的社会结构,并依赖其社区或殖民地生存。蜜蜂聚居区可以容纳多达20,000只蜜蜂。蜜蜂寻找花蜜的植物时,花粉棒是覆盖其后腿的毛发。在下一朵花上,一些花粉擦掉并施肥。这样,蜜蜂可以帮助改善水果生产。蜜蜂仅在美国就播种了大约130种不同的水果、花卉、坚果和蔬菜。农民显然依赖蜜来授粉作物,例如水果和坚果,但数千只蜜聚居区近年来已经消失。这对农民来说可能是个破坏性的问题。能做点什么吗?见两个北加州研究人员,寻找办法确保我们总是有种花作物。

    Summary
    ::摘要

    • Insects are considerable competitors for human food sources, particularly crop plants.
      ::昆虫是人类食物来源,特别是作物植物的大量竞争者。
    • Most flowering plants, including many that are components of agricultural crops, are critically dependent on insects to mediate their reproduction through pollination.
      ::大多数花卉植物,包括许多作为农作物组成部分的花卉植物,都严重依赖昆虫通过授粉调节繁殖。
    • Experiments conducted using the fruit fly drosophila have led to important scientific discoveries in biology.
      ::利用水果苍蝇浮雕进行的实验已导致生物学领域的重要科学发现。
    • Hematophagous insects sometimes inadvertently spread diseases that are harmful to humans.
      ::血友病昆虫有时无意中传播有害人类的疾病。

    Review
    ::回顾

    1. Insects sometimes destroy crop plants. What are some downsides to using pesticides?
      ::昆虫有时会破坏作物作物。
    2. What are some advantages to doing experiments on drosophila?
      ::做血友病实验有什么好处?
    3. How has the discovery of homeobox genes in drosophila impacted our understanding of genetics?
      ::在德罗索菲拉发现的同源箱基因如何影响我们对遗传学的理解?
    4. How have insects proven useful for forensic scientists?
      ::昆虫如何被证明对法医科学家有用?