一个英美科研小组说，我们最古老的祖先与恐龙同一时代，根据该小组的计算，现有灵长目动物(包括人)的最后的共同祖先出现于8150万年前的白垩纪。这一看法打乱了一个已经充满争论的研究领域。根据分子系统发育理论(这一理论可以通过基因突变率确定两个物种分化的时间)计算，灵长目动物从动物中分化出来的时间为9000万年前。而以经过鉴定的化石为依据的古生物学者则认为，这个时间大约为5500万年前。下列叙述符合文意的是（）。
A．灵长目动物(包括人)的最早的共同祖先出现于8150万年前的白垩纪
B．人类最古老的祖先与恐龙是同一时间出现在地球上的
C．这一观点的提出是以有关数字的计算为基础的
D．这一观点使有关灵长目动物的起源的研究充满了争议
相关热点： 灵长目
相关问题推荐
这段文字意在强调（ ）。
A:生物多样性是人类赖以生存的基础
B:如何保护地球生物多样性
C:多样的地球生物的种类正呈锐减趋势
D:人类活动对地球生态系统产生严重影响
A.偶蹄目
B.奇蹄目
C.灵长目
D.啮齿目
When global warming finally came, it stuck with a vengeance. In some regions, temperatures rose several degrees in less than a century. Sea levels shot up nearly 400 feet, flooding coastal settlements and forcing people to migrate inland. Deserts spread throughout the world as vegetation shifted drastically in North America, Europe and Asia. After driving many of the animals around them to near extinction, people were forced to abandon their old way of life for a radically new survival strategy that resulted in widespread starvation and disease. The adaptation was farming: the global-warming crisis that gave rise to it happened more than 10,000 years ago.As environmentalists convene in Rio de Janeiro this week to ponder the global climate of the future, earth scientists are in the midst of a revolution in understanding how climate has changed in the past and how those changes have transformed human existence. Researchers have begun to piece together an illuminating picture of the powerful geological and astronomical forces that have combined to change the planet’s environment from hot to cold, wet to dry and back again over a time period stretching back hundreds of millions of years.Most importantly, scientists are beginning to realize that the climatic changes have had a major impact on the evolution of the human species. New research now suggests that climate shifts have played a key role in nearly every significant turning point in human evolution: from the dawn of primates （灵长目动物）some 65 million years ago to human ancestors rising up to walk on two legs, from the huge expansion of the human brain to the rise of agriculture. Indeed, the human history has not been merely touched by global climate change, some scientists argue, it has in some instances been driven by it.The new research has profound implications for the environmental summit in Rio. Among other things, the findings demonstrate that dramatic climate change is nothing new for planet Earth. The benign （宜人的）global environment that has existed over the past 10,000 years—during which agriculture, writing, cities and most other features of civilization appeared—is a mere bright spot in a much larger pattern of widely varying climate over the ages. In fact, the pattern of climate change in the past reveals that Earth’s climate will almost certainly go through dramatic changes in the future—even without the influence of human activity.
1. Farming emerged as a survival strategy because man had been obliged（ ）.2. Earth scientists have come to understand that climate（ ）.3. Scientists believe that human evolution（ ）.4. Evidence of past climatic changes indicates that（ ）.5. The message the author wishes to convey in the passage is that（ ）.
A.to give up his former way of life B.to leave the coastal areas C.to follow the ever-shifting vegetation D.to abandon his original settlement问题2： A.is going through a fundamental change B.has been getting warmer for 10,000 years C.will eventually change from hot to cold D.has gone through periodical changes问题3： A.has seldom been accompanied by climatic changes B.has exerted little influence on climatic changes C.has largely been affected by climatic changes D.had had a major impact on climatic changes问题4： A.human activities have accelerated changes of Earth’s environment B.Earth’s environment will remain mild despite human interference C.Earth’s climate is bound to change significantly in the future D.Earth’s climate is unlikely to undergo substantial changes in the future问题5： A.human civilization remains glorious though it is affected by climatic changes B.mankind is virtually helpless in the face of the dramatic changes of climate C.man has to limit his activities to slow down the global warming process D.human civilization will continue to develop in spite of the changes of natureHuman vision like that of other primates（灵长目）has evolved in an arboreal（丛林）environment.______(46)
In the course of evolution,members of the primate line have acquired large eyes while the nose has shrunk.______ (47) Of mammals（哺乳动物）only humans and some primates enjoy color vision.______(48)Horses live in a single-color world.
Light visible to human eyes,however,occupies only a very narrow band in the whole electromagnetic spectrum（光谱）.Ultraviolet rays（紫外线）are invisible to humans though ants and honeybees are sensitive to them.______(49)The world would look terribly different if human eyes were、 sensitive to infrared radiation（红外线）.Then instead of the darkness of night,we would be able to move easily in a strange shadowless world.______(50)
But human eyes excel in other ways. They are in fact remarkably discerning in color gradation. The color sensitivity of normal human vision is rarely surpassed even by complicated technical devices. _________（50）A:Humans have no direct perception of infrared rays.B:In the dense complex world of a tropical forest,it is more important to see well than to develop an acute sense of smell.C:That gives the eye a wilder view.D:The red flag is black to the bull.E:There are different mammals in tropical forest.F: In this world,objects glowed with varying degrees of intensity.
When global warming finally came, it stuck with a vengeance (异乎寻常的). In some regions, temperatures rose several degrees in less than a century Sea levels shot up nearly 400 feet flooding coastal settlements and forcing people to migrate inland. Deserts spread throughout the world as vegetation shifted drastically in North America, Europe and Asia. After driving many of the animals around them to near extinction, people were forced to abandon their old way of life for a radically new survival strategy that resulted in widespread starvation and disease. The adaptation was farming: the global-warming crisis that gave rise to it happened more than 10,000 years ago.As environmentalists convene in Rio de Janeiro this week to ponder the global climate of the future, earth scientists are in the midst of a revolution in understanding how climate has changed in the past-and how those changes have transformed human existence. Researchers have begun to piece together an illuminating picture of the powerful geological and astronomical forces that have combined to change the planes environment from hot to cold, wet to dry and back again over a time period stretching back hundreds of millions of years.Most important scientists are beginning to realize that the climatic changes have had a major impact on the evolution of the human species. New research now suggests that climate shifts have played a key role in nearly every significant turning point in human evolution: from the dawn of primates (灵长目动物) some 65 million years ago to human ancestors rising up to walk on two legs from the huge expansion of the human brain to the rise of agriculture. Indeed, the human history has not been merely touched by global climate change, some scientists argue, it has in some instances been driven by it.The new research has profound implications for the environment summit in Rio. Among other things, the findings demonstrate that dramatic climate change is nothing new for planet Earth. The benign(宜人的) global environment that has existed over the past 10,000 years—during which agriculture writing, cities and most other features of civilization appeared—is a mere bright spot in a much larger pattern of widely varying climate over the ages. In fact, the pattern of climate change in the past reveals that Earth’s climate will almost certainly go through dramatic changes in the future—even without the influence of human activity.41. Farming emerged as a survival strategy because man had been obliged（ ）.42. Earth scientists have come to understand that climate（ ）.43. Scientists believe that human evolution（ ）.44. Evidence of past climatic changes indicates that（ ）.45. The message the author wishes to convey in the passage is that（ ）.
A.to give up his former way of life B.to leave the coastal areas C.to follow the ever-shifting vegetation D.to abandon his original settlement
问题2：
A.is going through a fundamental change B.has been getting warmer for 10,000 years C.will eventually change from hot to cold D.has gone through periodical changes
问题3：
A.has seldom been accompanied by climatic changes B.has exerted little influence on climatic changes C.has largely been affected by climatic changes D.has had a major impact on climatic changes
问题4：
A.human activities have accelerated changes of Earth’s environment B.Earth’s environment will remain mild despite human interference C.Earth’s climate is bound to change significantly in the future D.Earth’s climate is unlikely to undergo substantial changes in the future
问题5：
A.human civilization remains glorious though it is affected by climatic changes B.mankind is virtually helpless in the face of the dramatic changes of climate C.man bas to limit his activities to slow down the global warming process D.human civilization will continue to develop in spite of the changes of nature