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Don't wash those fossils!
Standard museum practice can wash away DNA.
1.Washing, brushing and varnishing fossils — all standard conservation
treatments used by many fossil hunters and museum curators alike — vastly
reduces the chances of recovering ancient DNA.
2.Instead, excavators should be handling at least some of their bounty with
gloves, and freezing samples as they are found, dirt and all, concludes a paper
in the Proceedings of the National Academy of Sciences today.
3.Although many palaeontologists know anecdotally that this is the best way
to up the odds of extracting good DNA, Eva-Maria Geigl of the Jacques Monod
Institute in Paris, France, and her colleagues have now shown just how important
conservation practices can be.This information, they say, needs to be hammered
home among the people who are actually out in the field digging up bones.
4.Geigl and her colleagues looked at 3,200-year-old fossil bones belonging to
a single individual of an extinct cattle species, called an aurochs.The fossils
were dug up at a site in France at two different times — either in 1947, and
stored in a museum collection, or in 2004, and conserved in sterile conditions
at -20 oC.
5.The team's attempts to extract DNA from the 1947 bones all failed.The newly
excavated fossils, however, all yielded DNA.
6.Because the bones had been buried for the same amount of time, and in the
same conditions, the conservation method had to be to blame says Geigl."As much
DNA was degraded in these 57 years as in the 3,200 years before," she says.
Wash in, wash out
7.Because many palaeontologists base their work on the shape of fossils
alone, their methods of conservation are not designed to preserve DNA, Geigl
explains.
8.The biggest problem is how they are cleaned.Fossils are often washed
together on-site in a large bath, which can allow water — and contaminants in
the form of contemporary DNA — to permeate into the porous bones."Not only is
the authentic DNA getting washed out, but contamination is getting washed in,"
says Geigl.
9.Most ancient DNA specialists know this already, says Hendrik Poinar, an
evolutionary geneticist at McMaster University in Ontario, Canada.But that
doesn't mean that best practice has become widespread among those who actually
find the fossils.
10.Getting hold of fossils that have been preserved with their DNA in mind
relies on close relationships between lab-based geneticists and the excavators,
says palaeogeneticist Svante P bo of the Max Planck Institute for Evolutionary
Anthropology in Leipzig, Germany.And that only occurs in exceptional cases, he
says.
11.P bo's team, which has been sequencing Neanderthal DNA, continually faces
these problems."When you want to study ancient human and Neanderthal remains,
there's a big issue of contamination with contemporary human DNA," he says.
12.This doesn't mean that all museum specimens are fatally flawed, notes P
bo.The Neanderthal fossils that were recently sequenced in his own lab, for
example, had been part of a museum collection treated in the traditional way.But
P bo is keen to see samples of fossils from every major find preserved in line
with Geigl's recommendations — just in case.
Warm and wet
13.Geigl herself believes that, with cooperation between bench and field
researchers, preserving fossils properly could open up avenues of discovery that
have long been assumed closed.
14.Much human cultural development took place in temperate regions.DNA does
not survive well in warm environments in the first place, and can vanish when
fossils are washed and treated.For this reason, Geigl says, most ancient DNA
studies have been done on permafrost samples, such as the woolly mammoth, or on
remains sheltered from the elements in cold caves — including cave bear and
Neanderthal fossils.
15.Better conservation methods, and a focus on fresh fossils, could boost DNA
extraction from more delicate specimens, says Geigl.And that could shed more
light on the story of human evolution.
(640 words nature )
Glossary
Palaeontologists 古生物学家
Aurochs 欧洲野牛
Neanderthal (人类学)尼安德特人，旧石器时代的古人类。
Permafrost (地理)永冻层
Questions 1-6
Answer the following questions by using NO MORE THAN THREE WORDS for each
answer.
1.How did people traditionally treat fossils?
2.What suggestions do Geigl and her colleagues give on what should be done
when fossils are found?
3.What problems may be posed if fossil bones are washed on-site? Name
ONE.
4.What characteristic do fossil bones have to make them susceptible to be
contaminated with contemporary DNA when they are washed?
5.What could be better understood when conservation treatments are
improved?
6.The passage mentioned several animal species studied by researchers.How
many of them are mentioned?
Questions 7-11
Do the following statements agree with the information given in the passage?
Please write TRUE if the statement agrees with the writer FALSE if the statement
does not agree with the writer NOT GIVEN if there is no information about this
in the passage.
7.In their paper published in the Proceedings of the National Academy of
Sciences，Geigl and her colleagues have shown what conservation practices should
be followed to preserve ancient DNA.
8.The fossil bones that Geigl and her colleagues studied are all from the
same aurochs.
9.Geneticists don't have to work on site.
10.Only newly excavated fossil bones using new conservation methods suggested
by Geigl and her colleagues contain ancient DNA.
11.Paabo is still worried about the potential problems caused by treatments
of fossils in traditional way.
Questions 12-13
Complete the following the statements by choosing letter A-D for each
answer.
12.“This information” in paragraph 3 indicates:
[A] It is critical to follow proper practices in preserving ancient DNA.
[B] The best way of getting good DNA is to handle fossils with gloves.
[C] Fossil hunters should wear home-made hammers while digging up bones.
[D] Many palaeontologists know how one should do in treating fossils.
13.The study conducted by Geigl and her colleagues suggests:
[A] the fact that ancient DNA can not be recovered from fossil bones
excavated in the past.
[B] the correlation between the amount of burying time and that of the
recovered DNA.
[C] the pace at which DNA degrades.
[D] the correlation between conservation practices and degradation of
DNA.
Selling Digital Music without Copy-protection Makes Sense
A. It was uncharacteristically low-key for the industry’s greatest showman.
But the essay published this week by Steve Jobs, the boss of Apple, on his
firm’s website under the unassuming title “Thoughts on Music” has nonetheless
provoked a vigorous debate about the future of digital music, which Apple
dominates with its iPod music-player and iTunes music-store. At issue is
“digital rights management” (DRM)—the technology guarding downloaded music
against theft. Since there is no common standard for DRM, it also has the
side-effect that songs purchased for one type of music-player may not work on
another. Apple’s DRM system, called FairPlay, is the most widespread. So it came
as a surprise when Mr. Jobs called for DRM for digital music to be
abolished.
B. This is a change of tack for Apple. It has come under fire from European
regulators who claim that its refusal to license FairPlay to other firms has
“locked in” customers. Since music from the iTunes store cannot be played on
non-iPod music-players (at least not without a lot of fiddling), any iTunes
buyer will be deterred from switching to a device made by a rival firm, such as
Sony or Microsoft. When French lawmakers drafted a bill last year compelling
Apple to open up FairPlay to rivals, the company warned of “state-sponsored
piracy”. Only DRM, it implied, could keep the pirates at bay.
C. This week Mr. Jobs gave another explanation for his former defence of DRM:
the record companies made him do it. They would make their music available to
the iTunes store only if Apple agreed to protect it using DRM. They can still
withdraw their catalogues if the DRM system is compromised. Apple cannot license
FairPlay to others, says Mr Jobs, because it would depend on them to produce
security fixes promptly. All DRM does is restrict consumer choice and provide a
barrier to entry, says Mr Jobs; without it there would be far more stores and
players, and far more innovation. So, he suggests, why not do away with DRM and
sell music unprotected? “This is clearly the best alternative for consumers,” he
declares, “and Apple would embrace it in a heartbeat.”
D. Why the sudden change of heart? Mr Jobs seems chiefly concerned with
getting Europe’s regulators off his back. Rather than complaining to Apple about
its use of DRM, he suggests, “those unhappy with the current situation should
redirect their energies towards persuading the music companies to sell their
music DRM-free.” Two and a half of the four big record companies, he helpfully
points out, are European-owned. Mr Jobs also hopes to paint himself as a
consumer champion. Apple resents accusations that it has become the Microsoft of
digital music.
E. Apple can afford to embrace open competition in music players and online
stores. Consumers would gravitate to the best player and the best store, and at
the moment that still means Apple’s. Mr Jobs is evidently unfazed by rivals to
the iPod. Since only 3% of the music in a typical iTunes library is protected,
most of it can already be used on other players today, he notes. (And even the
protected tracks can be burned onto a CD and then re-ripped.) So Apple’s
dominance evidently depends far more on branding and ease of use than
DRM-related “lock in”.
F. The music giants are trying DRM-free downloads. Lots of smaller labels
already sell music that way. Having seen which way the wind is blowing, Mr Jobs
now wants to be seen not as DRM’s defender, but as a consumer champion who
helped in its downfall. Wouldn’t it lead to a surge in piracy? No, because most
music is still sold unprotected on CDs, people wishing to steal music already
can do so. Indeed, scrapping DRM would probably increase online-music sales by
reducing confusion and incompatibility. With the leading online store, Apple
would benefit most. Mr Jobs’s argument, in short, is transparently self-serving.
It also happens to be right.
Notes to Reading Passage 1
1. low-key:
抑制的，受约束的，屈服的
2. showman:
开展览会的人, 出风头的人物
3. unassuming:
谦逊的, 不夸耀的, 不装腔作势的
4. iPod：
(苹果公司出产的)音乐播放器
5. iTunes store：
(苹果公司出产的)在线音乐商店
6. get off person’s back:
不再找某人的麻烦，摆脱某人的纠缠
7. gravitate:
受吸引，倾向于
8. unfazed:
不再担忧，不被打扰
Questions 1-7
Do the following statemets reflect the claims of the writer in Reading
Passage 1?
Write your answer in Boxes 1-7 on your answer sheet.
TRUE if the statement reflets the claims of the writer
FALSE if the statement contradicts the claims of the writer
NOT GIVEN if it is impossbile to say what the writer thinks about this
1. Apple enjoys a controlling position in digital music market with its iPod
music-player and iTunes music-store.
2. DRM is a government decree issued with a purpose to protect downloaded
music from theft by consumers.
3. Lack of standardization in DRM makes songs bought for one kind of music
player may not function on another.
4. Apple has been criticized by European regulators since it has refused to
grant a license FairPlay to other firms.
5. All music can be easily played on non-iPod music devices from Sony or
Microsoft without too much fiddling.
6. Apple depends far more on DRM rather than branding for its dominance of
the digital music devices.
7. If DRM was cancelled, Sony would certainly dominate the international
digital music market.
Questions 8-10
Choose the appropriate letters A-D and write them in boxes 8-10 on your answe
sheet.
8. Which of the following statements about Mr. Jobs’ idea of DRM is NOT
TRUE?
A. DRM places restrictions on consumer’ choice of digital music products
available.
B. DRM comples iTunes buyers to switch to a device made by Sony or
Microsoft.
C. DRM constitutes a barrier for potential consumers to enter digital music
markets.
D. DRM hinders development of more stores and players and technical
innovation.
9. The word “unfazed” in line 3 of paragraph E, means___________.
A. refused
B. welcomed
C. not bothered
D. not well received
10. Which of the following statements is TRUE if DRM was scapped?
A. Sony would gain the most profit.
B. More customers would be “locked in”.
C. A sudden increase in piracy would occur.
D. Online-music sales would probably decrease.
Questions 11-14
Complete the notes below.
Choose NO MORE THAN THREE WORDS from Reading Passage 1 for each answer.
Write your answers in boxes 11-14 on your answer sheet.
Mr. Steve Jobs, the boss of Apple, explains the reason why he used to defend
DRM, saying that the company was forced to do so: the record companies would
make their music accessible to …11...only if they agreed to protect it using
DRM; they can still…12…if the DRM system is compromised. He also provides the
reason why Apple did not license FairPlay to others: the company relies on them
to …13….But now he changes his mind with a possible expectation that Europe’s
regulators would not trouble him any more in the future. He proposes that those
who are unsatisfactory with the current situation in digital music market should
…14… towards persuade the music companies to sell their music DRM-free.
