高中英语选修B1U5RevealingnatureAjourneyofdiscovery课件

1、Revealing natureRevealing natureHave you ever seen these mysterious animals?Have you ever seen these mysteLook at the page from a sciencemagazine and answer the questions.1. What do you know about these animals?What makes them special?Komodo dragon: It evolved in Australia and spread westward Duck-b

2、illed platypus: The oldest discovered fossil of it dates back to about 100,000 years ago Nautilus: It often considered “living fossils” They are all species that exit thousands of years on earth; They are old and rare (unusual).2. What other similar animals do you know about? Share your knowledge wi

3、th the class.Starting outLook at the page from a sciencKomodo dragon:(科莫多巨晰）Komodo dragons were first encountered by Western researchers in 1910. The researchers said the ancestor of the Komodo dragon most likely evolved in Australia and spread westward, reaching the Indonesian island of Flores 9000

4、00 years ago.Komodo dragon:(科莫多巨晰）The Komodo dragonThe Komodo dragon is the largest lizard in the world. It can grow to three metres in length and can weigh about 135 kilograms. Despite its size and weight, it can run for short distances at up to 20 kilometres per hour.The Komodo dragonDuck-billed p

5、latypus: The first scientists to examine a preserved platypus body judged it a fake in the late 18th century. The oldest discovered fossil of the modern platypus dates back to about 100000 years ago.Duck-billed platypus: The Duck-billed platypusThe duck-billed platypus is a small egg-laying mammal (

6、up to 60 cm in length) found only in Eastern Australia including Tasmania. As its name suggests, it has a mouth that looks like a ducks bill, while its thick fur and flat tail are similar to those of a beaver（海狸）. The Duck-billed platypusNautilusFossil records indicate that the nautilus has survived

7、 relatively unchanged for around 500 million years. That is why it is often given the name “living fossil.”高中英语选修B1U5RevealingnatureAjourneyofdiscovery课件1. How can seeds travel? How can this benefit plants?Seeds usually are carried by the wind, water, and animals.Plants can have a better chance at l

8、ife. Watch the video and answer the questions. Watch the video and answer th2. Can you think of another example of seeds travelling? Share it with the class. Dandelion seeds have little parachutes to catch the wind and go further; Humans can spread seeds if seeds get stuck to their clothing or shoes

9、. Dandelion seeds have little Understanding ideasA journey of DiscoveryUnderstanding ideasA journey oCharles Darwin and his Theory of Evolution Charles Darwin (1809-1882) was an English geologist and naturalist. In his famous book On the Origin of Species, Darwin proposed the theory that organisms (

10、individual life forms ) evolve extremely slowly. He stated that the organisms that were better suited to their environments would survive and pass on their favourable characteristics to the next generation, while the less suitable organisms would gradually die out. He called this process “natural se

11、lection.”Charles Darwin Charles Darwin and his Theory 1.What species do you recognize in the picture?Look at the evolutionary tree and answer the questions.Paramecium, earthworm, snail, crab, fish, tortoise, bird, horse, human, frog, alga, moss, fern, plant1.What species do you recogniz2 What factor

12、s can cause the process of evolution?The ever-changing environment of nature; environmental changes; population immigration; genetic mutation; cultural preferences.2 What factors can cause the pRead the passage and talk about your understanding of the title. Most commonly, people believe that a jour

13、ney means a trip from one place to another, especially over a long distance and literarily a journey refers to the process by which something gradually changes and develops. The title may indicate that Darwins research work leading to his discovery of evolution and the origin of species .Read the pa

14、ssage and talk abou A young man who had left medical school without completing his degree. Whats more, his father predicted in his letter that he would be “a disgrace to yourself and all your family.” Despite all this, his adventures on this ship would lead to one of the most important scientific di

15、scoveries of all time.Beagle The beginning of the journey A young man who had left meCharles Darwin was a geologist and naturalist, fascinated by rocks, plants and animals. Darwin studied: various living things in their natural environments and samples of the plants and animals he had collected.He n

16、oticed :that some species of animals were very similar to each other.On his journey on the BeagleCharles Darwin was a geologistAt that time, people believed that all species had appeared on Earth at the same time, and had not changed since. However, as he studied these, Darwin asked himself the ques

17、tions:Generate ideasHow did different species come to exist? Maybe animals evolved as they adapted to their changing environments？At that time, people believed On the Galapagos Islands :He noticed that there was a difference between the finches on each of the islands.Look for more evidenceIt seemed

18、the beaks had evolved according to what food was available on that particular island.On the Galapagos Islands :Look The Galapagos Islands(加拉帕戈斯群岛)在厄瓜多尔西方约1000公里的太平洋上，由14个散布在赤道附近的小岛组成。 Galapagos在西班牙语中的意思就是乌龟。此群岛正如其名，岛上有重量超过一百公斤的象龟，使达尔文一行人大为吃惊，另外，还有长达一公尺以上的鬣蜥，这种蜥蜴有住在海岸附近的海生型及住在内陆的陆生型，且两者不属同种。 The Gala

19、pagos Islands The Galapagos Islands elephant tortoises鬣 晰 Conolophus subcristatusThe Galapagos Islands elephanRare birds on the islandsRare birds on the islands Darwin suspected that the finches had evolved from a common ancestor, which had arrived on the islands a long time before and it had slowly

20、 evolved into many new species.Develop ideas Darwin suspected that theThe theory of Evolution: living things , including humans had evolved from lower forms of life.Propose a theoryToday , On the Origin of Species is regarded as one of the most important works ever written. It has changed ideas abou

21、t life on Earth forever. And it all began with the journey on the Beagle.The theory of Evolution: Propo Darwin was a determined man. He had strong curiosity and interests in science and was good at thinking and making discoveries.1 Why were many people “shocked”by Darwins theory?2 What kind of perso

22、n was Darwin according to the passage? At that time, many people believed that all species had appeared on Earth at the same time and had not changed since, but Darwins theory proposed that living things, including humans, had evolved from lower forms of life, which, as a result, shocked many people

23、.Think and Share Darwin was a determined man. Charles Darwin was a geologist and naturalist, fascinated by rocks, plants and animals. He left England on the ship, the Beagle, in 1831. The journey gave him the chance 1_(study) various living things in their natural environments. He noticed that some species of animals were very similar 2_ each other. At that time, people believed that all species had appeared on Earth at the same time, and 3_(change) since. But Darwin began to think differently. When the ship reached the Galapagos Islands