高中英语人教版必修高三27

[00:14.47]READIGN

[00:15.62]THE LANGUAGE OF HONEY-BEES

[00:18.08]There are many different varieties of bee.

[00:20.95]Some live in large groups like the honey-bee,

[00:23.56]and make their nests in trees or holes in the rocks.

[00:27.19]Other species 1 make their nests in holes in the ground.

[00:30.43]There are also varieties that do not live in groups at all.

[00:34.19]Among the different kinds of bee,

[00:36.23]it is the honey-bee that has interested scientists most because of the “language” they use to communicate with each other.

[00:43.89]The development of the modern beehive in 1851 made it possible to design experiments to research the language of honey-bees.

[00:52.72]Professor Karl von Frisch, a scientist from Austria,

[00:56.76]spent many years of his life researching the amazing ways honey-bees communicate in their dark hives.

[01:03.74]After working with bees of many years, Professor von Frisch was puzzled by something he had noticed again and again.

[01:12.20]When he placed little dishes of honey on a table,

[01:14.92]bees soon came.

[01:16.49]As soon as one be discovered the honey, many more came to it one after another in a short time.

[01:23.72]It seemed that one bee was able to communicate the news of food to other bees in its hive.

[01:29.36]How was this possible?

[01:30.80]To find out, von Frisch built a special hives,

[01:34.43]each with only one honeycomb.

[01:36.47]He built a transparent 2 wall through which he could observe what went to inside.

[01:41.20]In order to tell the bees apart, he painted some bees with little dots of colour.

[01:45.93]When a marked bee returned to the hive from the feeding table,

[01:49.37]von Frisch watched through the glass.

[01:52.01]To his surprise, the bee began to perform a dace on the surface of the honeycomb.

[01:57.42]First it made a circle to the right,

[01:59.98]then to the left.

[02:01.03]It repeated theses 3 circles over and over again.

[02:04.68]But that was not all.

[02:06.43]The dance seemed to excite the surrounding bees.

[02:09.20]They trooped behind the first dancer, copying its movements.

[02:13.72]Then the bees left the hive and went to the feeding place. The circle dance seems to communicate news of food. But what else?

[02:20.38]Von Frisch assumed that the dance conveyed more information.

[02:24.46]To find out whether his assumption 4 was correct,

[02:27.20]he set up two feeding places.

[02:29.47]One was close to the hive,

[02:31.33]the other was much farther away,

[02:33.97]beyond some trees.

[02:35.43]He marked all the bees that came to the nearby feeding place blue,

[02:39.79]and all the bees that went to the far-away place red.

[02:43.24]When the bees came back to the hive,

[02:45.28]von Frisch saw a curious sight.

[02:47.99]All the bees that had been at the nearby feeding place were doing the circling dance.

[02:53.24]The bees that had been at the distant feeding place were doing a completely different dance,a wagging 5 dance.

[03:00.09]The dancer ran in a straight line,

[03:02.44]wagging from side to side.

[03:04.40]Then it turned in a semicircle,

[03:06.64]ran straight again, and turned in another semicircle to the opposite side.

[03:11.79]It kept repeating the “steps” over and over.

[03:14.72]Things were clear now.

[03:16.36]It was evident that the circle dance told the bees about the location of the feeding place.

[03:21.40]It was also apparent 6 that the wagging dance,

[03:24.43]where the bee moved sideways sent another message about the feeding place.

[03:29.37]Next, von Frisch and his colleagues set up feeding place close to the hive.

[03:34.41]Then they slowly moved it farther and farther away.

[03:37.97]Back at the hive they watched the wagging dance closely.

[03:41.70]With a stop-watch, they counted how many times the bees repeated the dance during one minute.

[03:47.55]They discovered that the farther away the feeding station was,

[03:51.31]the slower the dance was.

[03:52.96]So another astonishing fact came to light.

[03:55.81]The number of wagging dances per minute told the exact distance to the feeding place

[04:01.03]They also found out that bees fly a maximum distance of 3.2 kilometres between their hive and feeding place.

[04:09.29]The remaining question for Professor von Frisch and his partners was to find out whether bees could tell each other the exact position of a feeding place.

[04:19.03]For example, was it possible for bees to communicate precise details such as north, south, southwest and southeast?

[04:27.57]To answer the question,

[04:29.22]Professor von Frisch and his colleagues would have to obtain enough data to provide an adequate account of the bees’ behaviour.

[04:36.66]After designing more experiments

[04:38.80]they were able to clarify the procedure by which bees communicate information that they use to find and fetch food.

[04:46.46]When honey-bees have discovered a feeding place,

[04:49.33]they fly directly to it from the hive.

[04:51.79]After a short time a line of bees fly to and from the hive like a thin stream.

[04:57.82]Centuries ago, the word “bee-line” was created and today the expression “to make a beeline for someone or something” means to go quickly along a straight course for somebody or something.

[05:11.04]For his lifetime’s work in studying the communication of animals,

[05:15.09]including hone-bees, Professor Karl von Frisch was awarded a Noble Prize in 1973,

[05:22.04]which he shared with two other scientists.

[05:24.91]He died in 1982.

[05:27.37]INTEGRATING SKILLS

[05:32.33]Reading

[05:33.48]PRIMATES 8

[05:35.02]Like all other living creatures,

[05:37.37]human beings belong to a group of other animals that share certain characteristics.

[05:41.60]Zoologists place us in a group called primates,

[05:45.05]which include other mammals such as apes and monkeys.

[05:48.19]Among the key features found in primates are hands and feet that can grasp and often have opposable thumbs and toes.

[05:55.63]That means that primates are better than other animals at holding,

[05:59.18]moving and using objects.

[06:00.72]Indeed, many primates, most notably 9,

[06:03.89]human beings, have learnt to make and use tools.

[06:07.12]Primates also have a better sense of touch and the primate 7 brain is larger-compared to body size-than that of other animals.

[06:14.39]Depending on the size of the brain,

[06:16.42]primates are divided into two groups:

[06:19.06]higher primates (human beings and apes) and lower primates.

[06:23.50]There are some 183 species of primates and they are also sometimes divided into two other groups:

[06:31.55]new world primates,

[06:33.20]which are small monkeys that live in trees, such as the spider monkey and the night monkey;

[06:39.23]old world primates include monkeys, apes and humans.

[06:43.38]They are bigger and spend more time on the ground.

[06:46.62]There are several important differences between apes and monkeys:

[06:50.85]apes have no tail, nearly all monkeys do;

[06:54.62]apes tend to be larger and walk more upright;

[06:58.14]apes use sight more than smell.

[07:00.78]Apes also have more developed brains and give birth to fewer young,

[07:05.64]which need a long time to grow up.

[07:08.28]Zoologists also make a distinction between great apes (including gorillas 10 and chimpanzees_ and lesser 11 apes.

[07:16.14]Most primates are social animals that live in groups and communicate with each other.

[07:21.60]A few live alone

[07:23.45]Gorillas live in groups of one male and several females,

[07:27.71]and chimpanzees live in groups of many males and many females.

[07:32.39]While their societies are different,

[07:34.84]they all communicate and behave in advanced ways.

[07:38.27]Primates use facial expressions,

[07:41.11]body language and sounds to express themselves and they can even use colour and smell to communicate.

[07:48.19]Sometimes they warn each other of danger,

[07:50.75]and they also communicate simply to keep in touch.

[07:54.12]Our closest relative among the primates is the chimpanzee,

[07:58.93]an intelligent great ape that lives in western and central Africa.

[08:03.34]Chimpanzees are about 50 centimeters to metre tall and weight around 25 to 50 kilogrammes

[08:11.60]Males are larger then females and can be up to 1.2 metres tell and weigh 70 kilogrammes.

[08:19.54]Chimpanzees have very long arms and are covered with black hair.

[08:24.19]They use the same senses as we do and their feet and hands are similar to ours,

[08:30.35]except that chimpanzees still have opposable toes and can grasp thins with their feet.

[08:37.02]Their diet is also similar to ours-they eat meat and plants-even if they sometimes feast 12 on thins we may find disgusting,

[08:46.55]such as insects and ants.

[08:49.06]Modern science has allowed us to discover that human beings and chimpanzees are closer than we thought-our genes 13 are more than 95% similar!

[08:59.61]Because chimpanzees and other great apes are so close to us,

[09:04.47]scientists have conducted many experiments in order to find out whether other primates can do what we do.

[09:10.71]Scientists who study animal psychology 14 have trained chimpanzees to do all kinds of things humans do,

[09:17.66]such as solving problems and even suing 15 language.

[09:21.50]While these experiments are interesting and useful,

[09:24.95]it is important to remember that they many not always tell us much about how chimpanzees think and what they are able to do.

[09:32.19]The reason is simple: what the chimpanzees are trained to do is not natural to them,

[09:37.83]nor does it make much sense to the animals.

[09:40.86]What may be of greater importance is to observe how primates live in the wild.

[09:45.48]How do they adapt to a changeable environment?

[09:48.36]Some animals have physical adaptations,

[09:51.10]such as the stripes of a zebra, which many help it hide from enemies,

[09:55.64]o r the body of a camel, which helps it survive in the desert.

[09:59.80]Other animals have learnt to behave in certain ways or even use primitive 16 tools.

[10:05.13]Chimpanzees use more tools than most other animals.

[10:08.57]They use long pieces of grass to catch insects,

[10:12.13]they use stones as missiles and to crack open nuts,

[10:15.44]such as the African walnut, and they use leaves to collect and drink water