Birds share more characteristics with dinosaurs than they do with other animals.
Some ancient dinosaurs were indistinguishable from modern birds.
All animals whose skulls share the characteristics of those of modern birds also have pelvic bones that are similar to those of modern birds.
Modern birds are dinosaurs.
All dinosaurs are birds.
第1题：
Millions of people are in danger of getting malaria because______.
A. some countries have not started a campaign against mosquitoes
B. new species of mosquitoes may survive today's sprays
C. malaria was once thought to be a very old evil of the world
D. present sprays are not as effective as people think
第2题：
骨骼系统的名称为()
A.RingArray
B.Wave
C.Sunlight
D.Bones
第3题：
"Hidden" Species May Be Surprisingly Common
Cryptic species animals that appear identical but are genetically quite distant—may be much more widespread than previously thought. The findings could have major implications in areas ranging from biodiversity estimates and wildlife management, to our understanding of infectious diseases and evolution.
Reports of cryptic species have increased dramatically over the past two decades with the advent of relatively inexpensive DNA sequencing technology. Markus Pfenninger and Klaus Schwenk, of the Goethe-Universitat, in Frankfurt, Germany, analyzed all known data on cryptic animal species and discovered that they are found in equal proportions throughout all major branches of the animal kingdom and occur in equal numbers in all biogeographieal regions.
Scientists had previously speculated that cryptic species were predominantly found in insects and reptiles, and were more likely to occur in tropical rather than temperate regions. "Species that are seemingly widespread and abundant could in reality be many different cryptic species that have low populations and are highly endangered. " Says Pfenninger. Until the genetic information of all species in at least one taxon is thoroughly studied, no one will know just how many cryptic species exist. "It could be as high as 30%. " Pfenninger says.
"I'm extremely surprised by their results. " Says Alex Smith of the University of Guelph in Ontario, Canada. "It's a call to arms to keep doing the broad kind of genetic studies that we are doing. "
Sampling as many individuals as possible, scientists hope to complete work on all fish and birds in another 5 to 10 years. Once either of these taxonomic groups is completed, Pfenninger says researchers will be able to decide how many cryptic species exist throughout the animal kingdom.
Examples of cryptic species include the African elephant. A 2001 study found the elephants were actually two genetically distinct, non-interbreeding species, the African bush elephant and the African elephant. The species are currently listed as vulnerable and threatened, respectively, by the World Conservation Union (WCU).
The reclassifications are more than an academic exercise. They define populations that have evolved independently of each other and whose genetic differences can have significant consequences. In the early 1900s misidentification of mosquito species based on morphology confused attempts to control malaria in Europe. Ultimately, what was thought to be a single species was actually made up of six sibling species, only three of which transmitted the disease. "The basic unit in biology is always the species, and you have to know what you are dealing with. " Pfenninger says. Much previous research is now no longer used, he says, because it is not clear what species was being studied.
Which of the following about the significance of the research on cryptic species is NOT true?
A．The results of the research can help the development of many other research areas.
B．The results of the research can help the development of biodiversity estimates.
C．The results of the research can help our understanding of infectious disease evolution.
D．The results of the research can help our understanding of "survival of the fittest. "
第4题：
第5题：
The loss of biological diversity has become most spectacularly noticeable in extinction or decline of populations of large and well-known animals.Many animal species have become extinct since the 1700’s, among them the California grizzly bear, the dodo, and the passenger pigeon.Hundreds of other animal species are threatened.In North America, endangered species include the black-footed ferret, the California condor, the desert tortoise, and the whooping crane.
Most species in danger of extinction anywhere in the world are suffering from the intrusion (侵入) of human beings.The Asian elephant, for example, has become an endangered species due to the expansion of the human population throughout its range in southern Asia.In Africa, the African elephants are being killed off for their tusks.Monkeys and other primates throughout the world are threatened by hunting, capture for medical use, and the destruction of their habitats.And the rhinoceroses, lions, and other large mammals of the African savanna (grassy plains with scattered trees) compete for land and life with some of the most rapidly growing human populations in the world.
The loss of biological diversity is most severe, however, in the tropical rain forests.The forests of the tropics are particularly vulnerable to disturbance because the soils have a low capacity for retaining nutrients.Most of the forests’ nutrient elements are held in the tissues of plants.When loggers and farmers destroy existing plant cover, the nutrients are washed from the land into streams, and the land itself becomes less able to support life.Destruction of these forests destroys the habitat of hundreds, sometimes thousands, of species from such creatures as the howler monkey and indigo macaw, to less visible species of plants, insects, and microbes, many of which are not yet known to science.
1.The author points out that species extinction ().
A.is most noticeable in North America
B.is mainly taking place among large animals
C.quickened with industrialization of the society
D.never took place before the 1700’s
2.Which of the following is NOT mentioned with regard to human intrusion?
A.Elephants are killed off for their tusks
B.Some primates are hunted for medical use
C.Growing human population results in the competition for land and life among animals
D.Men live increasingly on animals as their source of food.
3.The chief cause of the gradual disappearance of biological diversity is ().
A.human cruelty
B.human interference
C.the increase of human population
D.the disappearance of the forests
4.In tropical forests，().
A.animals live a hard life due to competition
B.a lot of species die out for lack of food
C.rains constitute the major threat to species
D.a greater number of animals are yet to be known
5.It can be inferred that species extinction ().
A.proceeds of a faster rate than noticeable
B.is the worst among well-known animals
C.is the most severe in Africa
D.is chiefly due to competition among species
第6题：
Is that your pencil shar．pener?（作否定回答）
No，________ ________
第7题：
A、species plurimus;许多种
C、species plurimus;亚种
第8题：
People are confused in their attempts to control malaria in Europe in the early 1900s, because scientists ______.
A．identified only one mosquito species instead of six species
B．thought only three mosquito species transmitted disease
C．thought there was only one mosquito species
D．did not know what species was being studied
第9题：
第10题：
简述下列概念的区别： species；strain