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TPO 7 Lecture 2 Biology

l          Pro: So, that is how elephant uses infra sound. Now, let‘s talk about the other

and the acoustic spectrums, sound that is too high for humans to

hear---ultrasounds. Ultrasound is used by many animals that detected and

some of them seen(sent) out very high frequency sounds. So, what is a good

example? Yes, Kayo.

Kayo: Well, bats, since there is (they are )all blind, bets have to use sound for, you know,

to keep them from flying in the things(in to things ).

Pro: That is echolocation. Echolocation is pretty self-explanatory; using

echoes reflected sound waves to located things. As Kayo said that bat used for

navigation and orientation.

Naval / navel

And what is else. Make.

Make: Well, finding food is always important, and I guess not becoming food

for other animals.

Pro: Right, on both accounts. Avoiding other predators, and locating prey,

typically insects that fly around it at night. Before I go on, let me just respond

something Kayo was saying--- this idea that is bats are blind. Actually, there

are some species of bats, the one that don‘t use echolocation that do rely on

their vision for navigation, but its true for many bats, their vision is too weak to

count on. Ok, so quick some (summary) rays how some echolocation works. The bats emit the

ultrasonic pulses, very high pitch sound waves that we cannot hear.

single vibration of sound, light, electric current, etc

l          Frequency / interval: time between two events / heartbeat /

l          Diagram: n drawing or plan that uses simple lines rather than realistic details to explain or illustrate a machine, structure, process, etc

And then, they analyze the echoes, how the waves bound back. Here, let me finish the

style (this)diagram (before)I started it before the class. So the bat sends out the pulses, very

focus (bursts)birds of sound, and echo bounds back. You know, I don‘t think I need to

draw the echoes, your(will) reading assignment for the next class; it has diagram

shows this very clearly. So, anyway, as I were saying, by analyzing this echo,

the bat can determine, say, if there is wall in a cave that needs to avoid, and

how far away it is. Another thing uses the ultrasound to detect is the size and

the shape of objects. For example, one echo they quickly identified is one way

associated with moff(moth)( insect like a butterfly but less brightly coloured, flying mainly at night and

nocturnal / diurnal

attracted to bright lights), which is common prey for a bat, particularly a moff

meeting(beating) its wings. However, moff happened to have major advantage over

most other insects. They can detect ultrasound; this means that when the bat

approaches, the moff can detect the bat‘s presence. So, it has time to escape

to safety, or else they can just remain motionless. Since, when they stop

meeting their wings, they will be much hard(harder) for the bat to distinguish from, oh…

a leave or(leaf) some other object.

Now, we have tended to underestimate just how

sophisticated the ability that animals that use ultrasound are. In fact, we kinds

of assume that they were filtering a lot out. The ways are sophisticated radar

on our system can ignore the echo from the stationary object on the ground.

Radar are does this to remove ground clutter(things lying about untidily), information about the hills or

buildings that they doesn‘t need. But bats, we thought they were filtering out

kinds of information, because they simply couldn‘t analyze it. But, it looks as

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sophisticated  [so'phis·ti·cat·ed || sə'fɪstɪkeɪtɪd]

adj. seasoned, worldly-wise; refined, cultured; complex, intricate, complicated

we are wrong. Recent there was the experiment with trees and specific

species of bat. A bat called: the laser spear nosed bat. Now , a tree should be

huge and acoustic challenge for bat, right? I mean it got all kinds of surfaces

with different shapes and angles. So, well, the echoes from trees are going to

be massive and chaotic acoustic reflection, right, not like the echo from the

moff. So, we thought for a long time that the bat stop their evaluation as simply

that is tree. Yet, it turns out that is or at least particular species, cannot only tell

that is trees, but can also distinguish between a pine tree, deciduous tree(deciduous / indeciduous / sedulous / perseverance/ persistence ), like

a maple or oak tree, just by their leaves. And when I say, leaves, I mean pine

needles too. Any idea on how we would know that?

Stu: Well, like with the moff, could be their shape?

Pro: You are on the right track---it actually the echo of all the leaves as whole

the matters. Now, think, a pine trees with little densely packed needles. Those

produced a large number of fain(faint) reflection in which what‘s we called as: a

smooth of echo. The wave forms were very even, but an oak which has fewer

but bigger leaves with stronger reflections, produces a gigots(jagged)(gigantic) wave form, or

what we called: a rough echo. And these bats can distinguish between a two,

and not just was trees, but with any echo come in smooth and rough shape.

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0500

TPO 7 Conversation

Stu: Hi, I am a new here and I couldn't come to our student orientation and I'm

wondering if you can give me a few quick points(pointers) just about library. I‘d really

appreciate it.

Pro: Sure. I will be glad to. What's your major area of study?

Stu: Latin American Literature.

Pro: OK. Well, over here's the section where we have language, literature and

arts. And if you go down stairs you will find history section. Generally, the

students who concentrated in Latin American literature find themselves

research in history section a lot.

Stu: Hum, you are right. I am a transfer student and I've already done a year in

another university so I know how the research can go that spent a lot of time

on history section. So how long can I borrow books for?

Pro: Our loan period is a month. Oh I should also mention that we have an

inter-library loan service. If you need to get to hold a book that not in our library,

there is a truck that runs between our library and a few public and university

libraries in this area. It comes around three times a week.

Stu: It's great! At my last school, it takes really a long time to get the materials I

needed. So when I had a project, I had to make a plan away in advance. This

sounds much faster. Another thing I was wondering is: is there a place where I

can bring my computer and hook it up?

Pro: Sure. There is a whole area here on the main floor where you can bring a

laptop and plug it in for power but on top of that we also have a connection for

the internet that every seat.

Stu: Nice, so I can do the all research I need to do right here in the library. All I

have the resources, all the books and the information I need right here in one

place.

Pro: Yeah. That's the idea. I am sure you'll need photo copiers too. There is

down the hall to the left. We have system where you have to use copy cards so

you'll need to buy a card from the front desk. You would insert it into the

machine and you read it into the copies.

Stu: How much do you get charge?

Pro: Seven cents a copy.

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Stu: Hum, that is not too bad. Thanks. Hum, where is the collection of the rare

books?

Pro: Rare books are upon the second floor. There is in the separate room

where the temperature controlled, to preserved old paper in them. You need to

get special permission to access, and then you have to need to wear gloves to

handle them because the oil in our hands, you know, can destroy the paper.

And gloves prevent that so we have a basket of gloves in the room.

Stu: Ok. Thanks. I suppose that all I need to know. You've been very helpful.

Thanks.

Pro: Anytime. Bye

Stu: Bye.