Đề kiểm tra chất lượng ôn thi THPT Quốc gia môn Tiếng Anh Lớp 12 - Năm học 2017-2018 - Đề số 207

 SỞ GD&ĐT VĨNH PHÚC
TRƯỜNG THPT LIỄN SƠN
(Đề thi gồm: 05 trang)
ĐỀ KTCL ÔN THI THPT QUỐC GIA NĂM 2017-2018
Môn: TIẾNG ANH – ĐỀ SỐ 207
Thời gian làm bài: 60 phút, không kể thời gian phát đề
Họ và tên thí sinh:. SBD:
Mark the letter A, B, C, or D on your answer sheet to indicate the word whose underlined part differs from the other three in pronunciation in each of the following questions. 
Question 01: A. wounded	B. combined	C. considered	D. believed
Question 02: A. research	B. resent	C. resemble	D. resist
Mark the letter A, B, C, or D on your answer sheet to indicate the word that differs from the other three in the position of primary stress in each of the following questions. 
Question 03: A. describe	B. descent	C. design	D. descant
Question 04: A. disappear	B. recommend	C. understand	D. volunteer
Mark the letter A, B, C, or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions. 
Question 05: Mrs Phuong, along with her students from Ha Noi, are planning to take part in charity in remote areas
	A. along with	B. from	C. are	D. remote areas
Question 06: Thai Nguyen High School is a place in that I used to study when I was a child.
	A. in that	B. to study	C. when	D. a child 
Question 07: Helen Killer, who was both blind and deafness, overcame her inabilities with the help of her teacher, Ann Sulivan
	A. who	B. blind	C. deafness	D. inabilities
Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions. 
Question 08: Students who study far from home often have problems with_________ .
	A. houses	B. rooms	C. flats	D. accommodation
Question 09: In his latest speech, the Secretary General_________ the importance of wildlife conservation.
	A. stressed	B. excused	C. extorted	D. remained
Question 10: Some days of rest may help to_________ the pressure of work.
	A. reduce	B. lower	C. chop	D. crease
Question 11: Murder is a serious crime and one rarely_________ with it.
	A. get away	B. go away	C. turn away	D. come away
Question 12: She used to be very thin but she has_________ a bit now.
	A. filled in	B. finished off	C. filled out	D. fired away
Question 13: Jupiter is_________ planet in the solar system.
	A. the biggest	B. the big	C. the bigger	D. biggest
Question 14: Tommy wanted to know_________ .
	A. why his friends laughing	B. why did his friends laugh
	C. the reason why his friends laughing
	D. why his friends were laughing
Question 15: He was believed_________ 3 years ago.
	A. to have gone back hometown	B. to go back hometown
	C. to be go back hometown	D. to have been gone back hometown
Question 16: Education in England puts_________ force for children from 9 to 16 years old.
	A. into	B. on	C. off	D. through (thu xếp)
Question 17: I am_________ at paying my bills on time.
	A. hopeful	B. hopeless	C. hope	D. hoping
Question 18: Gold_________ in California in the 19 century
	A. has been discovered B. was discover	C. they discovered	D. was discovered
Question 19: She has read_________ interesting book.
	A. a	B. an	C. the	D. no article
Mark the letter A, B, C, or D on your answer sheet to indicate the most suitable response to complete each of the following exchanges. 
Question 20: -Mrs. Quyen: “Word hard! Otherwise, you may fail the exam” -Anna: “_______________”
	A. Ok, I will	B. I think you have to	C. I can’t fail it	D. I see
Question 21: -Teddy: “I’m very sorry for letting you wait for so long” -Maria: “_______________”
	A. Don’t apologize. I’ve just arrived here.	B. You’re welcome
	C. It doesn’t matter. Thank you	D. My pleasure. Don’t worry about it
Mark the letter A, B, C, or D on your answer sheet to indicate the word CLOSEST in meaning to the underlined word in each of the following questions 
Question 22: During their five-decade history the Asian Games have been advancing in all aspects.
	A. going off	B. going over	C. going by	D. going ahead
Question 23: The International Union for Conservation of Nature Red List is a comprehensive catalogue of the conservation status of species.
	A. complete	B. rational	C. understandable	D. valuable
Mark the letter A, B, C, or D on your answer sheet to indicate the word(s) OPPOSITE in meaning to the underlined word(s) in each of the following questions. 
Question 24: Your experience with oil well fires will be invaluable to the company in case of trouble
	A. precious	B. priceless	C. important	D. worthless
Question 25: A thrifty buyer chases fruits and vegetables in season.
	A. professional	B. economical	C. careful	D. extravagant
Mark the letter A, B, C, or D on your answer sheet to indicate the sentence that is closest in meaning to each of the following questions 
Question 26: Were it not for the money, this job wouldn’t be worthwhile.
	A. This job offers a poor salary.
	B. This job is rewarding at all.
	C. The only thing that makes this job worthwhile is the money.
	D. Although the salary is poor, the job is worthwhile.
Question 27: John was not here yesterday. Perhaps he was ill.
	A. John needn’t be here yesterday because he was ill.
	B. Because of his illness, John shouldn’t have been here yesterday.
	C. John might have been ill yesterday, so he was not here.
	D. John must have been ill yesterday, so he was not here.
Question 28: “If I were you, I would go to the doctor.” David said to Claudia.
	A. David advised Claudia not to go to the doctor.
	B. David told Claudia that he would go to see the doctor.
	C. David advised Claudia to go to the doctor.
	D. David told Claudia to become a doctor.
Mark the letter A, B, C, or D on your answer sheet to indicate the sentence that best combines each pair of sentences in the following questions 
Question 29: He did not work hard. He failed the exam.
	A. Unless he had worked hard, he would have failed the exam.
	B. Even though he failed the exam, he didn’t work hard.
	C. If he had worked hard, he would have passed the exam.
	D. However hard he worked, he failed the exam.
Question 30: She doesn’t want to go to their party. We don't want to go either.
	A. Neither she nor we don’t want to go to their party.
	B. Neither we nor she wants to go to their party.
	C. Either we or she doesn't want to go to their party.
	D. Neither we nor she want to go to their party.
Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks. 
	When you read something in a foreign language, you frequently come across words you do not fully understand. Sometimes you (31)________ the meaning in a dictionary and sometimes you guess. The strategy you adopt depends very much upon the degree of accuracy you require and the time at your disposal.
	If you are the sort of person who tends to turn to the dictionary frequently, it is (32)________ remembering that every dictionary has its limitations. Each definition is only an approximation and one builds up an accurate picture of the meaning of a word only after meeting it in a (33)________ of contexts. It is also important to recognize the special dangers of dictionaries that translate from English into your native language and vice versa. If you must use a dictionary, it is usually far safer to consult an English-English dictionary.
	In most exams you are not permitted to use a dictionary. (34)________ you are allowed to use one, it is very time-consuming to look up words, and time in exams is usually limited. You are, therefore, forced to guess the meaning of unfamiliar words. When you come across unknown words in an exam text, it is very easy to panic. However, if you develop efficient techniques for guessing the meaning, you will overcome a number of possible problems and help yourself to understand far more of the text than you at first thought likely.
	Two strategies which may help you guess the meaning of a word are: using contextual clues, both within the sentence and outside, and making use of clues (35)________ from the formation of the word
Question 31: A. control	B. inspect	C. check	D. examine
Question 32: A. valuable	B. worth	C. essential	D. vital
Question 33: A. variation	B. multiple	C. diversity	D. variety
Question 34: A. Even if	B. Provided	C. Although	D. In case
Question 35: A. originated	B. extracted	C. derived	D. coming
Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions. 
	Animals have an intuitive awareness of quantities. They know without analysis the difference between a number of objects and a smaller number. In his book “The natural History of Selboure” (1786 ), the naturalist Gilbert White tells how he surreptitiously removed one egg a day from a plover‟s nest, and how the mother laid another egg each day to make up for the missing one. He noted that other species of birds ignore the absence of a single egg but abandon their nests if more than one egg has been removed. It has also been noted by naturalists that a certain type of wasp always provides five – never four, never six - caterpillars for each of their eggs so that their young have something to eat when the eggs hatch. Research has also shown that both mice and pigeons can be taught to distinguish between odd and even numbers of food pieces.
	These and similar accounts have led some people to infer that creatures other than humans can actually count. They also point to dogs that have been taught to respond to numerical questions with the correct number of barks, or to horses that seem to solve arithmetic problems by stomping their hooves the proper number of times.
	Animals respond to quantities only when they are connected to survival as a species – as in the case of the eggs – or survival as individuals - as in the case of food. There is no transfer to other situations or from concrete reality to the abstract notion of numbers. Animals can “count” only when the objects are present and only when the numbers involved are small – not more than seven or eight. In lab experiments, animals trained to “count” one kind of object were unable to count any other type. The objects, not the numbers, are what interest them. Animals admittedly remarkable achievements simply do not amount to evidence of counting, nor do they reveal more than innate instincts, refined by the genes of successive generations, or the results of clever, careful conditioning by trainers
 Question 36: What is the main idea of this passage?
	A. Although animals may be aware of quantities, they cannot actually count.
	B. Of all animals, dogs and horses can count best.
	C. Careful training is required to teach animals to perform tricks involving numbers
	D. Animals cannot “count” more than one kind of object.
Question 37: Why does the author refer to Gilbert White‟s book in line 2?
	A. To indicate that more research is needed in this field
	B. To show how attitudes have changed since1786.
	C. To provide evidence that some birds are aware of quantities.
	D. To contradict the idea that animals can count.
Question 38: The word “surreptitiously” is closest in meaning to________.
	A. quickly	B. occasionally	C. stubbornly	D. secretly
Question 39: The word “odd” refers to which of the following?
	A. numbers such as 1, 3, 5 and so on	B. lucky numbers
	C. numbers such as 2, 4, 6 and so on	D. unusual numbers
Question 40: The author mentions that all of the following are aware of quantities in some ways EXCEPT________.
	A. wasps	B. Plovers	C. caterpillars	D. mice
Question 41: The word “accounts” is closest in meaning to________.
	A. reasons	B. reports	C. deceptions	D. invoices
Question 42: How would the author probably characterize the people who are mentioned in the first line of the second paragraph________.
	A. As foolish	B. As demanding	C. As clever	D. As mistaken
Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions. 
	Life originated in the early seas less than a billion years after the Earth was formed. Yet another three billion years were to pass before the first plants and animals appeared on the continents. Life’s transition from the sea to the land was perhaps as much of an evolutionary challenge as was the genesis of life.
	What forms of life were able to make such a drastic change in lifestyle? The traditional view of the first terrestrial organisms is based on mega fossils-relatively large specimens of essentially whole plants and animals. Vascular plants, related to modern seed plants and ferns, left the first comprehensive mega fossil record. Because of this, it has been commonly assumed that the sequence of terrestrialization reflected the evolution of modern terrestrial ecosystems. In this view, primitive vascular plants first colonized the margins of continental waters, followed by animals that feed on the plants, and lastly by animals that preyed on the plant-eaters. Moreover, the mega fossils suggest that terrestrial life appeared and diversified explosively near the boundary between the Silurian and the Devonian periods, a little more than 400 million years ago.
	Recently, however, paleontologists have been taking a closer look at the sediments below this Silurian-Devonian geological boundary. It turns out that some fossils can be extracted from these sediments by putting the rocks in an acid bath. The technique has uncovered new evidence form sediments that were deposited near the shores of the ancient oceans- plant microfossils and microscopic pieces of small animals. In many instances the specimens are less than one-tenth of a millimeter in diameter. Although they were entombed in the rocks for hundreds of millions of years, many of them fossils consist of the organic remains of the organism.
	These newly discovered fossils have not only revealed the existence of previously unknown organisms, but have also pushed back these dates for the invasion of land by multicellular organisms. Our views about the nature of the early plant and animal communities are now being revised. And with those revisions come new speculations about the first terrestrial life-forms
Question 43: In what order did the organisms first appear on earth?
	A. vascular plants, plant-eating animals, carnivores
	B. carnivores, plant-eaters, megafossils
	C. mega fossils, prey hunters, plant-eaters
	D. seed plants, ferns, megafossils
Question 44: What can be inferred from the passage about the fossils mentioned in the third paragraph?
	A. They have not been helpful in understanding the evolution of terrestrial life.
	B. They were found in approximately the same numbers as vascular plant fossils.
	C. They are older than the mega fossils.
	D. They consist of modern life-forms.
Question 45: According to the theory that the author calls “the traditional view” what was the first form of life to appear on land?
	A. Bacteria	B. Meat-eating animals C. Plant-eating animals	D. Vascular plants
Question 46: What is the following paragraph likely to discuss?
A. the existence of previously unknown organisms
B. the revision of human views on the nature of early plant and animal communities
C. comparison and contrast between the first terrestrial life forms and newly discovered fossils
D. what the first terrestrial life forms might have been
Question 47: The word “entombed” is closest in meaning to________.
	A. crushed	B. trapped	C. produced	D. excavated
Question 48: Which of the following resulted from the discovery of microscopic fossils?
	A. Which of the following resulted from the discovery of microscopic fossils?
	B. Old techniques for analyzing fossils were found to have new uses
	C. The origins of primitive sea life were explained.
	D. Assumptions about the locations of ancient seas were changed.
Question 49: With which of the following conclusions would the author probably agree?
A. The evolution of terrestrial life was as complicated as the origin of life itself.
B. The discovery of microfossils supports the traditional view of how terrestrial life evolved.
C. New species have appeared at the same rate over the course of the last 400 million years.
D. The technology used by paleontologists is too primitive to make accurate determinations about ages of fossils.
Question 50: According to the passage, what happened about 400 million years ago?
	A. Many terrestrial life-forms died out
	B. New life-forms on land developed at a rapid rate
	C. The mega fossils were destroyed by floods.
	D. Life began to develop in the ancient seas.
______THE END______
 SỞ GD&ĐT VĨNH PHÚC
TRƯỜNG THPT LIỄN SƠN
(Đề thi gồm: 05 trang)
ĐỀ KTCL ÔN THI THPT QUỐC GIA NĂM 2017-2018
Môn: TIẾNG ANH – ĐỀ SỐ 207
Thời gian làm bài: 60 phút, không kể thời gian phát đề
Họ và tên thí sinh:. SBD:
Mark the letter A, B, C, or D on your answer sheet to indicate the word whose underlined part differs from the other three in pronunciation in each of the following questions. 
Question 01: A. wounded	B. combined	C. considered	D. believed
Question 02: A. research	B. resent	C. resemble	D. resist
Mark the letter A, B, C, or D on your answer sheet to indicate the word that differs from the other three in the position of primary stress in each of the following questions. 
Question 03: A. describe	B. descent	C. design	D. descant
Question 04: A. disappear	B. recommend	C. understand	D. volunteer
Mark the letter A, B, C, or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions. 
Question 05: Mrs Phuong, along with her students from Ha Noi, are planning to take part in charity in remote areas
	A. along with	B. from	C. are	D. remote areas
Question 06: Thai Nguyen High School is a place in that I used to study when I was a child.
	A. in that	B. to study	C. when	D. a child 
Question 07: Helen Killer, who was both blind and deafness, overcame her inabilities with the help of her teacher, Ann Sulivan
	A. who	B. blind	C. deafness	D. inabilities
Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions. 
Question 08: Students who study far from home often have problems with_________ .
	A. houses	B. rooms	C. flats	D. accommodation
Question 09: In his latest speech, the Secretary General_________ the importance of wildlife conservation.
	A. stressed	B. excused	C. extorted	D. remained
Question 10: Some days of rest may help to_________ the pressure of work.
	A. reduce	B. lower	C. chop	D. crease
Question 11: Murder is a serious crime and one rarely_________ with it.
	A. get away	B. go away	C. turn away	D. come away
Question 12: She used to be very thin but she has_________ a bit now.
	A. filled in	B. finished off	C. filled out	D. fired away
Question 13: Jupiter is_________ planet in the solar system.
	A. the biggest	B. the big	C. the bigger	D. biggest
Question 14: Tommy wanted to know_________ .
	A. why his friends laughing	B. why did his friends laugh
	C. the reason why his friends laughing
	D. why his friends were laughing
Question 15: He was believed_________ 3 years ago.
	A. to have gone back hometown	B. to go back hometown
	C. to be go back hometown	D. to have been gone back hometown
Question 16: Education in England puts_________ force for children from 9 to 16 years old.
	A. into	B. on	C. off	D. through (thu xếp)
Question 17: I am_________ at paying my bills on time.
	A. hopeful	B. hopeless	C. hope	D. hoping
Question 18: Gold_________ in California in the 19 century
	A. has been discovered B. was discover	C. they discovered	D. was discovered
Question 19: She has read_________ interesting book.
	A. a	B. an	C. the	D. no article
Mark the letter A, B, C, or D on your answer sheet to indicate the most suitable response to complete each of the following exchanges. 
Question 20: -Mrs. Quyen: “Word hard! Otherwise, you may fail the exam” -Anna: “_______________”
	A. Ok, I will	B. I think you have to	C. I can’t fail it	D. I see
Question 21: -Teddy: “I’m very sorry for letting you wait for so long” -Maria: “_______________”
	A. Don’t apologize. I’ve just arrived here.	B. You’re welcome
	C. It doesn’t matter. Thank you	D. My pleasure. Don’t worry about it
Mark the letter A, B, C, or D on your answer sheet to indicate the word CLOSEST in meaning to the underlined word in each of the following questions 
Question 22: During their five-decade history the Asian Games have been advancing in all aspects.
	A. going off	B. going over	C. going by	D. going ahead
Question 23: The International Union for Conservation of Nature Red List is a comprehensive catalogue of the conservation status of species.
	A. complete	B. rational	C. understandable	D. valuable
Mark the letter A, B, C, or D on your answer sheet to indicate the word(s) OPPOSITE in meaning to the underlined word(s) in each of the following questions. 
Question 24: Your experience with oil well fires will be invaluable to the company in case of trouble
	A. precious	B. priceless	C. important	D. worthless
Question 25: A thrifty buyer chases fruits and vegetables in season.
	A. professional	B. economical	C. careful	D. extravagant
Mark the letter A, B, C, or D on your answer sheet to indicate the sentence that is closest in meaning to each of the following questions 
Question 26: Were it not for the money, this job wouldn’t be worthwhile.
	A. This job offers a poor salary.
	B. This job is rewarding at all.
	C. The only thing that makes this job worthwhile is the money.
	D. Although the salary is poor, the job is worthwhile.
Question 27: John was not here yesterday. Perhaps he was ill.
	A. John needn’t be here yesterday because he was ill.
	B. Because of his illness, John shouldn’t have been here yesterday.
	C. John might have been ill yesterday, so he was not here.
	D. John must have been ill yesterday, so he was not here.
Question 28: “If I were you, I would go to the doctor.” David said to Claudia.
	A. David advised Claudia not to go to the doctor.
	B. David told Claudia that he would go to see the doctor.
	C. David advised Claudia to go to the doctor.
	D. David told Claudia to become a doctor.
Mark the letter A, B, C, or D on your answer sheet to indicate the sentence that best combines each pair of sentences in the following questions 
Question 29: He did not work hard. He failed the exam.
	A. Unless he had worked hard, he would have failed the exam.
	B. Even though he failed the exam, he didn’t work hard.
	C. If he had worked hard, he would have passed the exam.
	D. However hard he worked, he failed the exam.
Question 30: She doesn’t want to go to their party. We don't want to go either.
	A. Neither she nor we don’t want to go to their party.
	B. Neither we nor she wants to go to their party.
	C. Either we or she doesn't want to go to their party.
	D. Neither we nor she want to go to their party.
Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks. 
	When you read something in a foreign language, you frequently come across words you do not fully understand. Sometimes you (31)________ the meaning in a dictionary and sometimes you guess. The strategy you adopt depends very much upon the degree of accuracy you require and the time at your disposal.
	If you are the sort of person who tends to turn to the dictionary frequently, it is (32)________ remembering that every dictionary has its limitations. Each definition is only an approximation and one builds up an accurate picture of the meaning of a word only after meeting it in a (33)________ of contexts. It is also important to recognize the special dangers of dictionaries that translate from English into your native language and vice versa. If you must use a dictionary, it is usually far safer to consult an English-English dictionary.
	In most exams you are not permitted to use a dictionary. (34)________ you are allowed to use one, it is very time-consuming to look up words, and time in exams is usually limited. You are, therefore, forced to guess the meaning of unfamiliar words. When you come across unknown words in an exam text, it is very easy to panic. However, if you develop efficient techniques for guessing the meaning, you will overcome a number of possible problems and help yourself to understand far more of the text than you at first thought likely.
	Two strategies which may help you guess the meaning of a word are: using contextual clues, both within the sentence and outside, and making use of clues (35)________ from the formation of the word
Question 31: A. control	B. inspect	C. check	D. examine
Question 32: A. valuable	B. worth	C. essential	D. vital
Question 33: A. variation	B. multiple	C. diversity	D. variety
Question 34: A. Even if	B. Provided	C. Although	D. In case
Question 35: A. originated	B. extracted	C. derived	D. coming
Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions. 
	Animals have an intuitive awareness of quantities. They know without analysis the difference between a number of objects and a smaller number. In his book “The natural History of Selboure” (1786 ), the naturalist Gilbert White tells how he surreptitiously removed one egg a day from a plover‟s nest, and how the mother laid another egg each day to make up for the missing one. He noted that other species of birds ignore the absence of a single egg but abandon their nests if more than one egg has been removed. It has also been noted by naturalists that a certain type of wasp always provides five – never four, never six - caterpillars for each of their eggs so that their young have something to eat when the eggs hatch. Research has also shown that both mice and pigeons can be taught to distinguish between odd and even numbers of food pieces.
	These and similar accounts have led some people to infer that creatures other than humans can actually count. They also point to dogs that have been taught to respond to numerical questions with the correct number of barks, or to horses that seem to solve arithmetic problems by stomping their hooves the proper number of times.
	Animals respond to quantities only when they are connected to survival as a species – as in the case of the eggs – or survival as individuals - as in the case of food. There is no transfer to other situations or from concrete reality to the abstract notion of numbers. Animals can “count” only when the objects are present and only when the numbers involved are small – not more than seven or eight. In lab experiments, animals trained to “count” one kind of object were unable to count any other type. The objects, not the numbers, are what interest them. Animals admittedly remarkable achievements simply do not amount to evidence of counting, nor do they reveal more than innate instincts, refined by the genes of successive generations, or the results of clever, careful conditioning by trainers
 Question 36: What is the main idea of this passage?
	A. Although animals may be aware of quantities, they cannot actually count.
	B. Of all animals, dogs and horses can count best.
	C. Careful training is required to teach animals to perform tricks involving numbers
	D. Animals cannot “count” more than one kind of object.
Question 37: Why does the author refer to Gilbert White‟s book in line 2?
	A. To indicate that more research is needed in this field
	B. To show how attitudes have changed since1786.
	C. To provide evidence that some birds are aware of quantities.
	D. To contradict the idea that animals can count.
Question 38: The word “surreptitiously” is closest in meaning to________.
	A. quickly	B. occasionally	C. stubbornly	D. secretly
Question 39: The word “odd” refers to which of the following?
	A. numbers such as 1, 3, 5 and so on	B. lucky numbers
	C. numbers such as 2, 4, 6 and so on	D. unusual numbers
Question 40: The author mentions that all of the following are aware of quantities in some ways EXCEPT________.
	A. wasps	B. Plovers	C. caterpillars	D. mice
Question 41: The word “accounts” is closest in meaning to________.
	A. reasons	B. reports	C. deceptions	D. invoices
Question 42: How would the author probably characterize the people who are mentioned in the first line of the second paragraph________.
	A. As foolish	B. As demanding	C. As clever	D. As mistaken
Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions. 
	Life originated in the early seas less than a billion years after the Earth was formed. Yet another three billion years were to pass before the first plants and animals appeared on the continents. Life’s transition from the sea to the land was perhaps as much of an evolutionary challenge as was the genesis of life.
	What forms of life were able to make such a drastic change in lifestyle? The traditional view of the first terrestrial organisms is based on mega fossils-relatively large specimens of essentially whole plants and animals. Vascular plants, related to modern seed plants and ferns, left the first comprehensive mega fossil record. Because of this, it has been commonly assumed that the sequence of terrestrialization reflected the evolution of modern terrestrial ecosystems. In this view, primitive vascular plants first colonized the margins of continental waters, followed by animals that feed on the plants, and lastly by animals that preyed on the plant-eaters. Moreover, the mega fossils suggest that terrestrial life appeared and diversified explosively near the boundary between the Silurian and the Devonian periods, a little more than 400 million years