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  • 昆虫

    Close-up of a horsefly's face, showcasing its large, colorful eyes and features.

    What dominates life on Earth?
    ::是什么主宰了地球上的生命?

    Well, by numbers, it's not humans. This may look like a scary creature from your worst nightmare, but it wouldn’t hurt a fly. In fact, it is a fly! The picture shows the charming portrait of a horsefly, up close and personal. Those big, striped, colorful orbs are its . Did you ever look through a kaleidoscope? If so, then you have an idea of what the world looks like to a horsefly.
    ::从数字来看,它不是人类。这看起来像你最坏的噩梦中的恐怖生物,但不会伤害苍蝇。事实上,它只是一只苍蝇!图片显示的是近距离和私人的一只马蝇的迷人肖像。那些大、条纹、多彩的金刚鹦鹉是它的迷人肖像。你有没有通过千叶眼看?如果是这样的话,那么你就会知道一只马蝇的世界长什么样。

    What other organs do insects like this horsefly have? Besides sensing their environment, what other functions do their organs serve?
    ::象这匹马的昆虫还有别的器官吗?除了感知它们的环境外,它们的器官还能起到什么其他作用?

    Insects
    ::昆虫

    Most members of the subphylum Hexapoda are insects (class Insecta). In fact, more than half of all known organisms are insects. There may be more than 10 million insect in the world, most of them yet to be identified. It’s clear that insects, and not humans, dominate life on Earth.
    ::六氯波达子植物的大多数成员都是昆虫(昆虫类 ) 。 事实上,所有已知生物中有一半以上是昆虫。 世界上可能有1 000多万昆虫,其中大多数还有待识别。 显然,昆虫而不是人类主宰着地球上的生命。

    A green cricket perched on a lush green leaf, showcasing its six legs.

    Hexapoda. A cricket on green leaf. Can you find the six legs attached to the thorax?
    ::绿叶上的板球 你能发现与胸腔相连的六条腿吗?

    Structure and Function of Insects
    ::昆虫的结构和功能

    Insects range in length from less than a millimeter to about the length of your arm. They can be found in most habitats , but they are mainly . Many can fly, so they are also aerial. Like other , insects have a head, thorax, and abdomen. They have a wide variety of appendages , including six legs attached to the thorax.
    ::昆虫的长度从不到一毫米到大约你的手臂长度不等。 它们可以在大多数栖息地中找到, 但主要是。 许多人可以飞, 所以它们也是空中的。 像其他昆虫一样, 昆虫有头、 胸和腹部。 它们有各种各样的附着物, 包括与胸角相连的六条腿。

    Insects have a pair of antennae for “smelling” and “tasting” chemicals. Some insects can also use their antennae to detect sound. Other sensory organs on the head include several simple eyes and a pair of compound eyes. The compound eyes let insects see images. Butterflies and bees can even see in color. For feeding, the head contains one pair of mandibles and two pairs of maxillae . Insects consume a wide range of foods, and their mouthparts have become specialized. Several variations are shown in Figure .
    ::昆虫有一对用于“熔炼”和“诱杀”化学品的天线,有些昆虫也可以使用天线探测声音,其他头部感官器官包括几只简单的眼睛和一对复合眼睛,复合眼睛让昆虫看到图像,蝴蝶和蜜蜂甚至可以看到颜色。喂食时,头部含有一对脏菜和两对麦花。昆虫消耗多种食物,它们的嘴部也变得专门化了。图中显示了几种不同之处。

    Variations in insect mouthparts adapted for different feeding methods.

    Mouthpart Specialization in Insects. The mouthparts of insects are adapted for different food sources. How do you think the different mouthparts evolved?
    ::昆虫的口腔专门化。昆虫的口部适应不同的食物来源。 你认为不同的口部是如何进化的?

    An insect’s abdomen contains most of the internal organs. Like other arthropods, insects have a complete digestive system . They also have an open circulatory system and . Like other terrestrial arthropods, they have trachea for air and Malpighian tubules for excretion .
    ::昆虫的腹部含有大部分内脏器官。 与其他节肢动物一样,昆虫有完整的消化系统。 它们也有开放的循环系统。 与其他陆生节肢动物一样,它们也有气管用于空气,而马尔皮琴管用于排泄。

    Insect Flight
    ::昆虫飞

    The main reason that insects have been so successful is their ability to fly. Insects are the only invertebrates that can fly and were the first to evolve flight . Flight has important advantages. It’s a guaranteed means of escape from nonflying predators . It also aids in the search for food and mates.
    ::昆虫之所以如此成功,主要是因为它们能够飞翔。 昆虫是唯一能够飞翔并率先进化飞行的无脊椎动物。 飞行具有重要优势。 这是从非飞食掠食者手中逃脱的可靠手段。 它也有助于寻找食物和伴侣。

    Insects generally have two pairs of wings for flight. Wings are part of the exoskeleton and attached to the thorax. Insect wings show a lot of variation. As you can see in Figure , butterfly wings are paper-thin, whereas beetle wings are like armor. Not all insect wings work the same way, either. They differ in how the are attached and whether the two pairs of wings work independently or together. Besides flight, wings serve other functions. They may protect the body (beetles), communicate visually with other insects (butterflies), or produce sounds to attract mates (katydids).
    ::昆虫通常有两对翅膀可以飞行。 翅膀是外骨骼的一部分, 附着在胸部上。 昆虫的翅膀变化很大。 如图所示, 蝴蝶的翅膀是纸质的, 甲虫的翅膀是像盔甲一样的。 不是所有的昆虫的翅膀都用同样的方式工作。 它们不同, 它们的翅膀是如何连接的, 以及两对翅膀是独立还是一起工作的。 除了飞行之外, 翅膀还有其他功能。 它们可以保护身体( 甲虫 ) , 与其他昆虫( 毛虫) 进行视觉交流, 或者产生吸引伴侣的声音( 甲虫 ) 。

    Beetle, butterfly, and katydid showcasing variations in insect wings for flight and other functions.

    Form and Function in Insect Wings. Beetles, butterflies, and katydids all have two pairs of wings that they use for flight. However, the wings are very different because they have other functions as well.
    ::昆虫翼中的形式和功能。甲虫、蝴蝶和卡提迪斯都有两对翅膀,它们都用来飞行。然而,翅膀非常不同,因为它们也有其他功能。

    Insect Reproduction
    ::昆虫复制

    Nearly all insects reproduce sexually. Some can also reproduce asexually. An example of an insect is shown in Figure .
    ::几乎所有昆虫都进行性繁殖,有些还可能进行性繁殖。图1显示了昆虫的例子。

    The insect life cycle of a mosquito, showing stages from egg to adult.

    Insect Life Cycle. This diagram represents the life cycle of a mosquito. Most insects have a similar life cycle.
    ::昆虫生命周期。本图代表蚊虫的生命周期,大多数昆虫的生命周期相似。

    When an insect egg hatches, a larva emerges. The larva eats and grows and then enters the pupa stage. The pupa is immobile and may be encased in a cocoon . During the pupa stage, the insect goes through metamorphosis . Tissues and appendages of the larva break down and reorganize into the adult form. How did such an incredible transformation evolve? Metamorphosis is actually very advantageous. It allows functions to be divided between life stages. Each stage can evolve adaptations to suit it for its specific functions without affecting the adaptations of the other stage.
    ::当昆虫蛋孵化时,幼虫会出现。幼虫会吃并生长,然后进入幼虫阶段。幼虫不动,可能会被笼罩在中。在幼虫阶段,昆虫会经历变形。幼虫的组织和附体会分解并重组成成人形。这样的不可想象的转变是如何演变的?变形实际上是非常有利的。它允许将功能分成生命阶段。每个阶段都可以根据它的具体功能进行适应,而不会影响其他阶段的适应。

    Insect Behavior
    ::昆虫行为行为

    Insects are capable of a surprising range of behaviors. Most of their behaviors, such as flying and mating , are instinctive. These are behaviors that don’t need to be learned. They are largely controlled by genes . However, some insect behaviors are learned. For example, ants and bees can learn where food is located and keep going back for more.
    ::昆虫的行为范围惊人。 大多数昆虫的行为,如飞行和交配,都是本能行为。 这些是不需要学习的行为。 它们基本上受基因控制。 但是,有些昆虫的行为是学得来的。 比如,蚂蚁和蜜蜂可以知道食物的所在地,继续往回走。

    Many species of insects have evolved complex social behaviors. They live together in large, organized colonies (see Figure ). This is true of ants, termites, bees, and wasps. Colonies may include millions of individual insects. Colony members divide up the labor of the colony. Different insects are specialized for different jobs. Some reproduce, while others care for the young. Still others get food or defend the nest.
    ::许多昆虫物种演变了复杂的社会行为。它们居住在大型、有组织的聚居区(见图 ) 。 蚂蚁、白蚁、蜜蜂和黄蜂都是如此。 殖民地可能包括数以百万计的个别昆虫。 殖民地成员将聚居地的劳动力分开。 不同的昆虫专门从事不同的工作。 有些昆虫繁殖, 另一些则照顾年轻人。 还有的则得到食物或保护巢穴。

    A tall termite nest in Australia, resembling a cathedral and standing 7.5 meters high.

    Termite Nest. This cathedral-like structure is the nest of a huge colony of termites in Australia. In fact, it is the world’s largest known termite nest. It towers 7.5 meters (25 feet) above the ground and houses millions of termites.
    ::白蚁巢。 这个像大教堂一样的结构是澳大利亚一个巨大的白蚁群的巢穴。 事实上,它是世界上最大的已知白蚁巢。 它在地面上高7.5米(25英尺 ) , 住着数以百万计的白蚁。

    Living in a large colony requires good . Ants communicate with chemicals called pheromones . For example, an ant deposits pheromones on the ground as it returns to the nest from a food source. It is marking the path so other ants can find the food. Honeybees communicate by doing a “ waggle dance .”
    ::生活在一个大殖民地需要良好的。蚂蚁与被称为费洛蒙的化学物质沟通。例如,当蚂蚁从食物来源回到巢穴时,在地面上储存了费洛蒙。它标记了这条路,让其他蚂蚁能找到食物。蜜蜂通过跳“跳舞”进行沟通。

    KQED: Ants: The Invisible Majority
    ::KQED: 蚂蚁: 隐形多数

    Most of us think ants are just pests. But not Brian Fisher. Known as “The Ant Guy,” he's on a mission to show the world just how important and amazing these little creatures are. In the process, he hopes to catalog all of the world's 30,000 ant species before they become casualties of habitat loss . 
    ::我们大多数人认为蚂蚁只是害虫。但Brian Fisher不是。他被称为“蚂蚁 ” ( The Ant Guy ) , 他的使命是向世界展示这些小生物的重要性和惊人性。在这个过程中,他希望在它们成为生境损失的伤亡之前,把世界上的3万只蚂蚁全部编成目录。

     

     

     

     

     

     

    KQED: Ladybugs: A Population of Millions
    ::KQED: 虫: 百万人口

    Ladybugs, also known as ladybird beetles, have a life cycle of four to six weeks. In one year as many as six generations of ladybird beetles may hatch. In the spring, each adult female lays up to 300 eggs in small clusters on plants where aphids are present. After a week the wingless larvae hatch. Both the ladybird beetle larvae and adults are active predators, eating only aphids, scales, mites and other plant-eating insects. The ladybugs live on the vegetation where their prey is found, which includes roses, oleander, milkweed and broccoli. Adult ladybugs don’t taste very good. A careless enough to try to eat one will not swallow it.
    ::虫(又称虫)的生命周期为4至6周。在一年中,可能有多达6代的虫孵化。在春天,每个成年雌虫在有虫子的植物上以小团群放置多达300个鸡蛋。一周后幼虫孵化无翅膀的幼虫。母虫幼虫和成年幼虫都是活跃的捕食者,只吃虫子、天秤、老鼠和其他植物食用昆虫。大虫生活在猎物所在的植物上,包括玫瑰、牛油、牛奶和花椰。成年母虫吃不饱,吃不饱。

    By late May to early June, when the larvae have depleted the food supply, the adults migrate to the mountains. There, they eat mainly pollen . The ladybugs gain fat from eating the pollen and this tides them over during their nine-month hibernation . Thousands of adults hibernate overwinter in tight clusters, called aggregates , under fallen leaves and ground litter near streams. In the clear, warmer days of early spring, the ladybugs break up the aggregates and begin several days of mating. 
    ::到5月底至6月初,当幼虫耗尽了食物供应时,成年人迁移到山区,在那里,他们主要吃花粉。在9个月冬眠期间,小虫从吃花粉中获取脂肪,这在9个月休眠期间使他们潮涨。数千个成年人在紧凑的团团内冬眠,称为集料,在落叶下,在溪流附近的泥土堆里。在春初的晴朗、温暖的几天里,小虫将聚集起来,开始数天的交配。

    Insects and Humans
    ::昆虫和人类

    Most humans interact with insects every day. Many of these interactions are harmless and often go unnoticed. However, insects cause humans a lot of harm. They spread human diseases. For example, the deadly bubonic plague of the middle ages was spread by fleas. Today, millions of people die each year from malaria , which is spread by mosquitoes. Insects also eat our crops. Sometimes they travel in huge swarms that completely strip the land of all plant material (see Figure ). On the other hand, we depend on insects for the very food we eat. Without insects to pollinate them, flowering plants—including many food crops—could not reproduce.
    ::多数人类每天都与昆虫发生互动,其中许多互动是无害的,往往无人注意。然而,昆虫对人类造成许多伤害,它们传播人类疾病。例如,中世纪致命的脑膜瘟疫是跳蚤传播的。今天,每年有数百万人死于疟疾,疟疾由蚊虫传播。昆虫也吃我们的作物。有时,它们游荡成群,使所有植物材料完全被土地剥去(见图 ) 。另一方面,我们依赖昆虫来获取我们所吃的食物。没有昆虫来授粉,花卉植物 — — 包括许多粮食作物 — — 就无法繁殖。

    A vast swarm of locusts in Mauritania overwhelms the landscape, threatening vegetation.

    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.
    ::在非洲毛里塔尼亚的非洲国家,一群蝗虫使中天笼罩在黑暗中。饥饿的昆虫将吞噬他们道路上几乎所有的植物。

    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, with a colony containing 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 fruit, flowers, nuts and vegetables in the United States alone. Farmers obviously depend on bees to pollinate crops, such as fruit and nuts, but in recent years thousands of bee colonies have disappeared. 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,依靠其社区或殖民地生存,有20,000只蜜蜂的聚居区。当蜜蜂寻找花蜜植物时,花粉棒将花毛串到覆盖其后腿的毛发上。在下一朵花上,一些花粉擦掉并施肥。这样,蜜蜂帮助改善水果生产。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,但近年来数千只蜜蜂聚居区已经消失。这对农民来说可能是个破坏性的问题。能做什么?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。

     

     

     

     

     

     

    Science Friday: The Road Best Traveled: A Tale of Ants, and the New Jersey Turnpike
    ::科学星期五:路程最佳旅行:蚂蚁的故事和新泽西岛的翻车

    For most people, getting stuck in a traffic jam on the New Jersey Turnpike is a grueling lesson in futility. However, in this video by Science Friday, Simon Garnier examines our collective behavior and how relatively simple organisms organize themselves so dynamically.
    ::对大多数人来说,被困在新泽西州翻车的交通堵塞中是徒劳无益的一课。 然而,在科学星期五的这段视频中,西蒙·加尼耶(Simon Garnier)审视了我们的集体行为以及相对简单的生物如何如此活跃地组织起来。

     

     

     

     

     

    Summary
    ::摘要

    • Insects are arthropods in the class Hexapoda. They are the most numerous organisms in the world.
      ::昆虫是Hexapoda类中的节肢动物,是世界上数量最多的有机体。
    • Most insects are terrestrial, and many are aerial.
      ::大多数昆虫是陆地的,许多是空中的。
    • Insects have six legs and a pair of antennae for sensing chemicals. They also have several eyes and specialized mouthparts for feeding.
      ::昆虫有六条腿和一对天线用于感测化学物质,还有几只眼睛和专用的喂养口袋。
    • Insects are the only invertebrates than can fly. Flight is the main reason for their success.
      ::昆虫是唯一不能飞的无脊椎动物 飞行是它们成功的主要原因
    • Insects may live in large colonies and have complex social behaviors.
      ::昆虫可能生活在大殖民地,具有复杂的社会行为。
    • Insects spread disease and destroy crops. However, they are essential for pollinating flowering plants.
      ::昆虫传播疾病,毁坏作物,但对于授粉开花植物至关重要。

    Review
    ::回顾

    1. List two traits that characterize insects.
      ::列出昆虫特征的两个特征。
    2. State two important advantages of flight in insects.
      ::说明昆虫飞行的两个重要优势。
    3. Give examples of insect behavior.
      ::举昆虫行为的例子。
    4. Present facts and a logical argument to support the following statement: “Insects dominate life on Earth.”
      ::目前的事实以及支持以下说法的合乎逻辑的论点:“昆虫主宰着地球上的生命。”
    5. Explain why distinctive life stages and metamorphosis are adaptive.
      ::解释为什么独特的生命阶段和变形是适应性的。
    6. Diagram an insect life cycle.
      ::昆虫生命周期图