Skill Review A-C

Репетитор по английскому языку онлайн
Skill Review A-C
√ Campus Life
√ Oceanography.
√ Psychology
√ Paleontology




1 Campus Life
W: Excuse me, I’m new here. Would you be able to give me some
    information about the Night Ride?

M: The shuttle bus? I sure can.

W: Great, when does it run?

M: Let’s see...I think the schedule has changed since last year, so
    just let me have a look...okay...here it is. It runs from 8:00 p.m.
    until 12:15 a.m.

W: Is there a fixed schedule? Does it come at regular intervals?

M: It runs approximately every fifteen minutes.

W: OK. Is that going to change in the winter quarter?

M: No, that’s the schedule for the fall, winter, and spring quarters.
    Since it’s only here to cater to student needs, it runs on a less
    frequent schedule in the summer since there aren’t as many
    students attending classes.

W: I see. So, now it runs Monday through Friday, right?

M: No no, the Night Ride only runs on school nights ...Sunday
    through Thursday.

W: Sundays, too? That’s great.

M: That’s right, but not Fridays.

W: I won’t need it Fridays. That’s when I review my lecture notes.
    I can do that at home. So, through the week, can I catch the
    Night Ride at the library? I usually study at the library.

M: Hmmm...the bus runs on a circuit through campus and the
    surrounding communities. The pick up points on campus are at
    Parrington Hall, the Communications Building, the HUB, Garfield
    Lane, and Meany Hall.

W: Isn’t Meany Hall that old building adjacent to the library tower?

M: Yes, that’s correct.

W: I see. So, I guess I could just catch it at Meany Hall. Where would
    I get dropped off?

M: There are no specific drop-off points. You just tell the driver
    where you want to go.

W: Really, he’ll take me right to my doorstep?

M: Sure, as long as your doorstep is within a mile of campus.

W: A mile? Hmmm...I think my place is probably a little more than
    a mile.

M: Well, you could go in that direction on the shuttle and walk the
    rest of the way. Or, you could get let off at one of the local bus
    stops.

W: Hmmm...maybe I’ll just take my bike. Can I take my bike on the
    shuttle?

M: Good question. I’m not sure. But maybe not. They haven’t got
    bike racks. Maybe you could do this: take your bike to the bus
    stop, lock it up, take the bus to school, and then on your way
    home you could take the shuttle and get dropped off at the bus
    stop where you left your bike.

W: Do you think my bike would be safe there?

M: Well, of course, those stops are not affiliated with the university,
    so I can’t really guarantee that. But I know other students haven’t
    had any trouble.

W: I might as well just ride my bike to school and back.

M: That’s another option. But then again, you can’t really ride your
    bike in the winter.

W: Why not?

M: Well, the winters here can be pretty harsh.

W: Oh yeah. Well, I guess I can try the bus out and see how well it
    works for me. Thanks for all of your help. I really appreciate it.

M: My pleasure.



2 Oceanography.
M: What exactly are reefs, and why are they so important? I hope
this lecture will give you some answers to these two questions.
Today, we will consider the history of reefs and the evolutionary
changes they have gone through. It is important to understand the
changing nature of a reef and how vulnerable it is to environmental
influences.
A coral reef is a bank of coral, the top of which can sometimes
be seen just above the sea. Reefs are some of the world’s most
diverse ecosystems. An ecosystem includes all the living things
in an area and the way in which they affect each other and the
environment. Coral reefs have been around for millions of years
and have undergone numerous changes over time. We can utilize
coral reef ecosystems as indicators of larger, global changes.
This is especially important today in assessing the effects human
activity may cause on the environment.
Reefs may be found in both tropical and temperate areas of the
world. They are geological features that support a huge diversity
of marine life and provide a habitat for sea life. The shape and
form of a reef depend on where it is located and what type of
forces the ocean subjects it to. Temperate reefs occur in colder
waters where the temperature averages below 18?C. They usually
form on existing rocky outcrops. Temperate reefs are not as well
known as tropical reefs, but they are still home to a diverse range
of species. Seaweeds such as coralline algae produce calcium
carbonate that helps build up these rocky reefs. Tropical reefs, on
the other hand, occur in warmer waters that average around
18?C and can reach into the high 20s. These reefs are built by
the animals that live there, especially algae and corals. Over time,
the reef grows by building on top of the calcium carbonate
skeletons of polyps.
W: Excuse me sir, what exactly are polyps?
M: Polyps? Polyps are small simple tube-shaped water animals. The
polyps divide and grow on top of their old skeletons or houses.
Now, as I said earlier, we can use coral reef ecosystems as indicators
of larger, global changes. All sorts of information about the
past can be obtained from rocks and coral cores. Coral reefs
can tell us things such as which times the Earth experienced a
rise or fall in sea levels. They can even inform us about events
such as ice ages, huge volcanic eruptions, and meteors falling
to Earth causing mass extinctions by wiping out whole species.
Modern corals grow in warm, clear, well-lighted and shallow
water. Since coral reefs grow best from the low tide line to
about a 20-meter depth, even relatively small changes in sea
level can have very dramatic effects on coral reef growth. Reefs
will always grow to the level of low tide. The location of fossils
in a reef is very important because by observing fossils in a reef,
we can accurately estimate sea level at the time the reef was
formed. Therefore, fossils help us chart the various changes in
sea level that have occurred over the years. Thanks to research
by marine scientists, we know that sea level change has been
going on continuously during the evolution of corals and reef
organisms. There have been 17 cycles of sea level rise and fall
in the last 2 million years.
So, how do marine scientists get their information? One method
they use is called coral coring. By drilling a vertical core through
the reef, it is possible to see periods of growth and decline in
the reef. It is possible to date these periods of growth and
decline by looking at fossils in the rock and measuring the types
of atoms present in the rock. The type of atoms present in the
rock can tell scientists lots about how old the rock is and what
the climate was like at the time. Sea level rise and fall may be
caused mainly by movements of the Earth’s crust and changes
in the amount of water locked up in the polar ice caps. As the
polar ice caps melt or freeze, sea levels around the world change.
So, coral is not just pretty to look at, it is also a great source of
information.



3 Psychology
W: We hear a lot of criticism from the baby boomers about the
younger generations. The stereotypical idea is that your parents’
generation thinks that young people are lazier, less respectful,
less goal-oriented, and so on. Now, perhaps this kind of criticism
is common to generation pairs, but there’s actually been some
interesting research in this area. Let’s take a look at what it shows.
Is the younger generation really so bad, or are the baby boomers
looking through distorted glasses, comparing their children to
their adult selves instead of themselves at the same age?
How is it that we can research such a topic? Well, psychologists
have been giving various psychological tests to samples of the
adolescent population since the 1960s. By comparing the data
from these tests for your generation against the data from your
parents’ generation, we can get a picture of what, if any, significant
differences there are.
One major test was the IQ test. IQ stands for Intelligence Quotient.
Intelligence is an idea that scientists use to describe why some
people are better at academic tasks than others. The results of
looking at IQ test scores from the past and from today show that
the younger generation today is significantly more intelligent
than their parents were in their adolescence. How significant?
10 points. This is a fairly large amount considering that IQ is only
really measurable within a range of 70 to 130 points. This means
that, on average, humans are increasing in intelligence by one
IQ point every four years. Interesting, isn’t it?
So, why would this be? Well, we have a few theories. First off,
nutrition may be a key factor. More different kinds of food are
more readily available today than ever before. This has been true
for many, many years, so every new generation is privileged
with better nutrition when developing in the womb. This is a
critical period in the development of the brain. Nutrition makes
a big difference during childhood as well. Think about what
your parents used to eat for breakfast. Bacon, eggs, sausage,
ham, steak...not a lot of vitamins!
Another theory is that as the world becomes more and more
complex, our brains have to develop more in order to cope with it.
The brain works just like a muscle. The more you use it, generally,
the stronger it gets. A good example is computers. My daughter
is six years old and has learned how to navigate the Internet,
burn a CD, save files to folders, and a number of other tasks that
her grandparents certainly can’t do! You know, when I was six, all
I had to learn how to do was turn on the TV and flip between
3 or 4 channels.
Your improved intelligence might also have something to do
with your upbringing. Responsibility and self-reliance are both
available and necessary at a much younger age than when I
was a child. There are very few stay-at-home parents anymore.
Many of you probably knew how to cook, clean, and do laundry
by the time you were in high school. Sad to say, I never learned
these things until I was in my mid-twenties.
So you’re smarter. Is that it? Well, no. You’ve also scored higher
than your parents on tests of extroversion. This means you are
more outgoing, more open with yourself, and less shy in social
settings. This is a great advantage in networking and getting
desirable jobs. If you are socially adept, an employer is more
likely to hire you.
So, why are you more extroverted? Well, once again, necessity
is the mother of invention. You spend a lot more time outside
of the family unit and with many different kinds of people.
Also, you are much more likely to move away from your home
town for university or for work, and you will probably move
more times in your life than my generation did. This means you
have to get out there and meet new people in order to maintain
a network of social support.
There is one disadvantage though. The young generation today
is more anxious and neurotic than their parents were at the same
age, meaning that youth today worry more. I suppose this is
understandable given the state of the world today, but it is also,
of course, a negative factor for health and well-being in general.



4 Paleontology.
M: All right, let’s get down to living fossils. If you have any questions,
please don’t hesitate to ask. Uh...make sure you take notes
because there’s always a question about this on the primary
exam. Where was I? Ah, yes living fossils.
Well...certainly, not all species on Earth have followed the usual
pattern whereby species last about 2 to 3 million years before
they are replaced. This number varies between different phyla, but
that’s an average figure. Evolution does its work, and older species
often die out because of climate changes and natural catastrophes.
Species that adapt well survive in the new conditions, and the cycle
continues. Some hardy species, though, have weathered the
ages and remain with us today. It’s truly amazing to think that
these plants and animals have adapted to so many changes. In
some cases, perhaps, there has been stability in their environment,
too. Nonetheless, these survivors are a scientific wonder because
of their success.
First of all, it’s important to realize that we have what are deemed
“living fossils,” but this isn’t precisely the same as a “lazarus
taxon.” I’ll explain that term soon. For now, let’s stick with living
fossils. A living fossil is a species of plant or animal that has
existed since far back in the geological record and has never
disappeared. These species haven’t changed their form at all
over an extensive period of time. What I mean is that they have
lasted much longer than the average of 2 to 3 million years that
I mentioned a few minutes ago. A great example of this is the
tuatara lizard in New Zealand. This wonderful reptile has been
around longer than the dinosaur. And we can find consistent
evidence of its existence as far back as 200 million years ago.
Tuataras are a single living species with no close living relatives,
but which are the survivors of a large and widespread group in
the fossil record. Another well-known example of this is the
ginkgo tree. Ginkgo trees used to be part of a large group of
plants, but, like tuataras, they’re now one of a kind. Perhaps
this has contributed to humanity’s fascination with them, imbuing
them with supposed healing properties. Anyway, that’s beside
the point, I suppose. The key thing is that, as with all true living
fossils, at no point have ginkgo trees disappeared from the fossil
record.
A lazarus taxon, or lazarus species, on the other hand, has done
just that. Having disappeared from the fossil record for a long
stretch, a living specimen is suddenly found. This is the case
with the famous coelacanth. That’s a tricky one to spell, so I’ll
write it on the board. Coelacanth: C-O-E-L-A-C-A-N-T-H. This
fish was formerly thought to be long extinct. In fact, scientists
can find no evidence of the coelacanth in the past 80 million
years of the fossil record. Against all expectations, a living one
was caught by fishermen near South Africa in 1938. Like the
biblical character Lazarus, the species seemed to miraculously
come back to life after everyone thought it was dead. It’s a mystery
why scientists can’t fill in that missing fossil information. Of course,
species do not just appear out of thin air, so all living lazarus
species are nonetheless considered living fossils. They’re merely in
a special category. Should a more recent example of a coelacanth
fossil be found, the missing link would be filled, and coelacanths
would cease to be a lazarus taxon. They would be reclassified
as just a regular living fossil.
OK, it’s time to wrap this up, I’m afraid...in summary, a living
fossil is a species that appeared long ago in the fossil record,
and it is still around in the same form. It has survived against
the odds, whereas most of its relatives have died out. Lazarus
taxons share these characteristics, but they form a special class
of living fossils because there is a gap in their fossil history.
Because of this gap, scientists formerly thought these species
had become extinct. Their sudden discovery on Earth today
places them in the lazarus category. Until that fossil record gap
is filled, they remain in that special category. I see we’re almost
out of time. Do any of you have questions?

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