【一起来听写】-楠瓜-脚踏实地

楠瓜UID：2693754

9.30早听写

http://blog.sina.com.cn/s/blog_86290bae0100x0k5.html

The Vikings
Listen to part of a lecture in an archeology class and answer the question.

Okay, let's discuss another ancient people called the Vikings. Many people think about horned helmeted raiders, farmers, and settlers when they discuss vikings. As a matter of fact, vikings were more than that, they also had religion, mainly Christianity. They valued family, were known as great warriers and traded with many countries. For the purpose of our discussion, we are going to concentrate on the trade aspect of the Vikings. The Vikings knew that piracy served a limited purpose by providing only an irregular income and at the same time realized that trade could provide a more regular means for providing wealth. This strong belief in trade led many of the Scandinavian vikings to trading goods rather than raiding villages and stealing what they wanted. They set up their trading spots in places like fishing camps or small trading stations, in both seasonal markets and densely settled towns. In some cases, these trading spots were the beginnings of larger towns which flourished during the viking age and were located in North-west, northern and eastern Europe, more commonly called Scandinavia. Believe it or not, some of these towns still exist today and in some cases have grown into cities. Some of the abandoned viking age towns and marketplaces have recently been excavated and numerous goods have been discovered. These discoveries include remains of glass and pottery and beads, possiblely from Asia. Some of what was left of the trade industries were also discovered, such as the remnants from the making of everyday and luxury objects of glass, bone, antler, wood, iron, bronze and precious metals.


Viking  n. 海盗,北欧海盗
Christianity   n. 基督教
Scandinavian  n. 斯堪的纳维亚人
spot  n. 地点, 场所
excavate  vt. 挖掘, 开凿
bead  n. (空心)小珠子；水珠；珠子项链
antler  n. 鹿角
bronze  n. 青铜；青铜色, 赤褐色；青铜艺术品, 铜牌


raider  n. 进行袭击、抢劫或搜查的人
raid   n. 突然袭击
piracy  n. 海盗行为,海上掠夺



http://blog.sina.com.cn/s/blog_86290bae0100x0m9.html

Windows

Listen to part of the lecture in an architecture class and answer the question.

Windows usually look like thay're all made of glass and wood. However, there is more to windows than meets the eye. Things that look like wood could be aluminum, vinyl or some other composite material. As people prefer things that are "low-maintenance", there has been an explosion in materials that look like wood being used for frames, they don't need sanding and painting and still look like high quality wood. Sometimes a layer of aluminum is used to coat the exterior surfaces of a window to provide a long-lasting and low-maintenance surface. It is called "cladding." I think I should write down the word on the board. It refers to the application of one material over another to provide a weather proof layer. For aluminum, there are fewer color options than with wood finishes and usually the thicker of the aluminum is the more durable it is. However, it doesn't have the insulating qualities of windows made of other materials so they're not widely used. Vinyl is another popular low-maintenance option. It can also be applied over other materials like wood or wood products. Like aluminum, the thicker the vinyl, the more durable it will be. Composite windows and vinyl windows are gaining popularity nowadays as non-wood, energy efficient and low-maintenance of alternatives which don't warp or rot like wood window can in extreme conditions.


composite  adj. 混合成的, 综合成的
vinyl  n. <化>乙烯基
explosion  n. 爆炸; 爆发；激增, 扩大
sand  vt. 用砂纸磨光；在某物上撒沙, 用沙覆盖
coat  vt. 为某物涂抹
cladding   n. 覆层
finish   n.末道漆
insulating  adj.绝缘的
warp   vt. & vi. 弄弯, 变歪
rot  vt. & vi. (使)腐烂, (使)腐朽


low-maintenance  维护费用低廉的

楠瓜UID：2693754

10.1
偷懒了~~~
先占楼后补上

楠瓜UID：2693754

10.2早听写

http://blog.sina.com.cn/s/blog_86290bae0100x2yv.html

Civil Engineering: Suspension Bridge
listen to part of a lecture on civil engineering in a journalism class.


Good morning class, today I brought in a picture of a specific kind of bridge called a suspension bridge. That bridge looks familiar to me.


Is it the Clinfton suspension Bride in Bristol, England?


Yes, you are right, you are really on the ball today. Can anyone tell me who built it and what is unique about the suspension bridge?


Well, the Clinfton suspension bridge was designed in 1830 by a man named Brunel, but he died before the bridge was finished. As his memorial, the bridge was finally completed in 1864.

Excellent, you are really with it today. Now, who can tell me about suspension bridges? Or is this question over your heads?


I think I can answer that. According to some books I've read about suspension bridges. The road deck is hanging from cables that are strung across a river like the Avon gorge in the picture. What makes a suspension bridge unique is that there is no support in the centre and the road deck hangs below the supports rather than resting upon them like other bridges.


Excellent, let me fill you in on some other details. Some of the oldest suspension bridges used ropes instead of cables, that were loosely thrown across a gorge or river. This olny allowed for people to hang as they crawled across. Soon after, wooden footways were added between the ropes. Unfortunately, these bridges were not convenient or safe for taking donkeys or carts across because of the swinging of the ropes and the loads were just too heavy for the bridge to bear. The suspension bridges that we use today like the one in the picture were first developed way back in the early 1800's. Civil Energineers such as Telford and Brunel thought of the idea of using towers to lift up the cables and using a frame to support and stiffen the bridge called a truss. The towers allowed the bridge to stay perfectly flat, which would give horses and carriages a means to cross. In a nutshell, Brnuel designed the first non-moving bridge. Today, the design of the suspension bridge is the same, but we use steel cables instead of iron links like those found on a bicycle chain.
In fact, Brunel's famous bridge still has the iron chain links.


How do suspension bridges hold the heavy weight of cars and trucks? In the past they only used horses and carriages, so the bridges didn't carry as much weight as they do now.


Good point, all modern bridges that you see today use huge steel cables to hold the roadway. These cables are hung over two towers and held concrete blocks at both ends of the bridge. Vehicle, such as cars and trucks push down on the roadway, and because the roadway is held up by hangers from the steel cables they can transfer for all the weight onto the two towers. This means that the two towers are always compressed, which allows them to transfer the forces to the ground or concrete blocks where they absorb the tension from the steel cables. Steel is the preferred material used in long suspension bridges because it can handle extremely heavy weight. Steel is stronger than iron and is also light in weight. A famous example can be seen in the Brooklyn bridge in New York, USA.


Are there any problems with a suspension bridge?


I'm glad you asked me that question. There have been a couple of disasters in regard to syspension bridges. If the engineers design a bridge that is too light or too flexible, the bridges will not be strong enough. They will begin to move and rock back and forth even in light winds and will eventually collapse into the gorge or river below.



journalism  n. 新闻业
memorial  n. 纪念碑, 纪念物
hang   vt. & vi. 悬, 挂, 垂下
deck  n.a floor built across a ship over all or part of its length 甲板, 层面
cable   n. (船只、桥梁等上的)巨缆, 钢索
strung  (string的过去式与过去分词)  vt. 装弦于, 上弦；用线串
gorge  n. 山峡, 峡谷；咽喉
crawl  vi. 爬, 爬行; 徐缓而行
footway   n. 小路,人行道
cart  n. 运货马车; 手推车
swing  vt. & vi. (使)摇摆, (使)摇荡
stiffen  vt. & vi. (使)变硬;(使)强硬
truss   vt. 捆绑  n. (干草的)一捆,一束,构架
carriage  n. 四轮马车; 车辆；车厢；举止, 仪态
hanger  n. 衣架
compress   vt. 压紧, 压缩
Steel  n. 钢
rock  vt. & vi. (使)来回摆动


on the ball   机警, 高明
way back   老早就,很久以前
push down   向下按, 推倒, 压倒
in regard to   关于…

楠瓜UID：2693754

10.3早听写

http://blog.sina.com.cn/s/blog_86290bae0100x3vn.html

Tattoo

Listen to part of a lecture in a health class and answer the question.


Let's look at this interesting piece of news. Oh, first, do any of you have a tattoo?

I've got an eagle on my back.

Anybody else? No? Okay. Did you know that 16 percent of adult Americans have tattoos? Christina Aguilera and Beyonce have tattoos. Do you think they are safe? Did you know that absolutely no national regulations exist? When you get a tattoo, you put yourself at risk, allergies to the dyes, keloid scarring and infections including have a hepatitis, tetanus and even HIV. Now, isn't that scary?
If you still want one, and you have thought about what it will look like in 30 years, there are some tips you should follow.
Everything should be clean and sanitary even the appearance of the person doing the Tattooing. Take a good look at the sterilizing equipment. Does it have a recent testing certificate? If you can, try to watch someone else getting tattooed. The needles in sterilized packages of course should be opened in front of the customer. There should be a biohazard container for ones that have been used. Watch the artist to see if he or she changes gloves after touching things other than needles. There are no regulations governing tattooing, but there are state licensing regulations. Look for the certificate on the wall. If the artist belongs to Alliance of professional tattooists that's a sign of good reputation. Be patient, your tattoo will take 7 to 10 days to heal.

tattoo  n. 文身；刺青；刺花   n. tattooist　文身的人
allergy  n. (对食物、花粉、虫咬等的)过敏症
dyes  n. 染料, 染色
keloid  n.瘢痕疙瘩,瘢痕瘤
scar  n. 伤痕, 伤疤; 精神上的创伤
hepatitis  n.肝炎
tetanus  n. 破伤风
sanitary  adj. 清洁的, 卫生的, 保健的
sterilize   vt. 消毒;使无菌    sterilizing  adj.无菌的    sterilized  adj. 已灭菌的
biohazard  n. (尤指带有微生物的生物工作所引起的)生物危害
artist  n. 能手
alliance  n. 结盟, 联盟



http://blog.sina.com.cn/s/blog_86290bae0100x3xp.html

Samuel Adu-Poku

Listen to part of a lecture in an education class and answer the question.

Recently, we discussed the research of Samuel Adu-Poku, an African Canadian. He considered the curriculum in the average North American School under the perspective of regarding Africa as being the cradle of civilization. He discussed how North American education disadvantages students of African descent by not recognizing Africa as being the source of many discoveries and knowledge. He explained how North American writers incorrectly attribute many discoveries and early knowledge to European sources.
Adu-Poku, recommended the reorganization of some North American art courses to provide a multicultural viewpoint that acknowledges African discoveries and to encourage African children to learn the traditions of their Afican ancestors. In total, Adu-Poku's research helped to expose our assumptions as readers and show us where we are positioned. For North American readers, this relative position would be different from that of Asian readers and both would be different from that of Adu-Poku. As a North American, I was made aware of my historical view relative to Great Britain and Europe. His writing made me aware of my position. Did any of you experience a shift in your viewpoint? Adu-Poku's research confronted me also with some of my assumptions. It certainly showed me how education can instill prejudicial attitudes that can mark learners for life and limit one's experience and views of others. I would like to think some more about this today. Specifically, I would like to examine other ways in which education is not an advantage.

perspective  n.观点, 想法
cradle  n. 摇篮
descent  n.血统, 出身, 门第
multicultural  adj. 多种文化的；反映多种文化的；适合于多种文化的
expose  vt. 曝光; 暴露; 显露
assumption  n. 假定, 臆断
instill  vt. <美>逐渐使某人获得(某种可取的品质);逐步灌输
prejudicial  adj. 引起偏见的;有损害的

飒飒11UID：3171458

楠瓜果断是个好同志啊~要跟你学习~
我还有好多日志要补啊~嘿嘿

楠瓜UID：2693754

谢谢班长！虽然练了好多天，比之前的速度和正确率都提高了不少，但现在做题错误率还是很高啊。觉得听写的时候可以反复听好多遍再把句子写出来，但实际考试的时候只有一遍，结果听不明白，把要点都遗漏过去了。我现在主要做TPO题，还要准备作品集和网申，估计每天也没那么多时间练听写了。以后可能不能做到天天听写了。
谢谢班长组织活动，辛苦了！一起努力！ 20# 飒飒11

楠瓜UID：2693754

10.4早听写

http://blog.sina.com.cn/s/blog_86290bae0100x5cd.html

Listen to part of a lecture in a biology class.

Professor:
OK, now I want to talk about an animal that has a fascinating set of defense mechanisms and that's the octopus. One of the unusual creatures that live in the sea. The octopus is prey to many species including humans, so how does it escape its predators? Well, let me back up here a second. Anyone ever heard of Proteus?
Proteus was god in Greek mythology who could change form. He could make himself look like a lion or a stone or a tree, anything you wanted, and he could go through a whole series of changes very quickly. Well, the octopus is the real world version of Proteus. Just like Proteus, the octopus can go through all kinds of incredible transformations. And it does this in three ways by changing color, by changing its texture and by changing its size and shape.
For me, the most fascinating transformation is when it changes its color. Its normal skin color, the one it generally presents is either red or brown or even grey and it's speckled with dark spots. But when it wants to blend in with its environment to hide from its enemies. It can take on the color of the its immediate surroundings, the ocean floor, a rock, a piece of coral, whatever. Charles?


Male Student:
Do we know how that works? I mean how they change colors?


Professor:
Well, we know that the reaction that takes place is not chemical in nature. The color changes are executed by two different kinds of cells in the octopus' skin, mainly by color cells on the skin surface called chromatophores.
Chromatophores consist of tiny sacks filled with color dye. There might be a couple hundred of these color sacks per square millimeter of the octopus skin and depending on the species they can come in as many as five different colors. Each one of these sacks is controlled by muscles. If the muscles are relaxed, the sack shrinks and all you see is a little white point. But if the muscles contract, then the sack expands and you can see the colors. And by expanding different combinations of these color sacks to different degrees, the octopus can create all sorts of colors. Yes, Elizabeth?


Female Student:
And just with various combinations of those five colors, they can recreate any color in their environment?


Professor:
Well, they can no doubt create a lot with just those five color, but you are tight, maybe they can't mimic every color around them, so that's where the second kind of cell comes in. Just below the chromatophores is a layer of cells that reflect light from the environment and these cells help the octopus create a precise match with the colors that surround them. The colors from the color sacks are supplemented with colors that are reflected from the environment and that's how they are able to mimic colors with such precision. So that's how octopuses mimic colors. But they don't just mimic the colors in their environment, they can also mimic the texture of objects in their environment. They have these litte projections on their skin that allow them to resemble various textures. The projections are called papillae.
If octopus was to have a rough texture it raises the papillae. If it wants to have a smooth texture flattens, it flattens out the papillae so it can acquire a smooth texture to blend in with the sandy bottom of the sea. So the octopus has the ability to mimic both the color and the texture of its environment. And it's truly amazing how well it can blend in with its surroundings. You can easily swim within a few feet of an octopus and never see it.


Male Student:
I read that they often hide from predators by squirting out a cloud of ink, or something like that.


Professor:
Yes, the octopus can release a cloud of ink if it feels threatened. But it doesn't hide behind it, as it generally believed. Um, the ink cloud is ... it serves to distract a predator while the octopus makes its escape. Now there is a third way that octopuses can transform themselves to blend in with or mimic their environment, and that's by changing their shape and size, well, at least their apparent size. The muscular system of the octopus enables it to be very flexible to assume all sorts of shapes and postures. So it can contract into the shape of a little round stone and sit perfectly still on the sea floor. Or it can nestle up in the middle of a plant and take the shape of one of the leaves. Even Proteus would be impressed I think.



octopus  n. 章鱼  octopuses复数
Proteus  n. 希腊海神,多变的人
version  n. 版本, 形式
spot  n. 斑点, 污点
immediate  adj.最接近的
execute  vt. 执行, 实现; 使生效
chromatophore   n. 色素胞,色素体
sack  n. 麻袋, 包
shrink  vt. & vi. 收缩; 退缩
expand  vt. & vi. 使…变大, 扩大, 扩张   expend   vt. 花费, 使用(钱等)做某事
mimic  vt. (尤指为了逗乐而)模仿；酷似
match  n. 相似之物, 相配之物
projection  n. 投掷,发射,喷射；投影,投影图；预测；推断；设想
resemble  vt. 像…, 类似于
papillae  n. <拉>乳头
squirt  vt. & vi. (指液体或粉末) 喷出,喷射
muscular  adj. (有关)肌(肉)的  muscle  n.
assume   vt.呈现
nestle   vt. & vi. 舒适而温暖地安定下来

back up   支持
a second  又一个;一秒钟
go through  完成, 做完
blend in   (使)(与…)和谐或协调
take on   呈现
takes place   發生
in nature  实际上, 性质上, 究竟
flatten out   变平,转为水平飞行
nestle up   依偎;紧靠着

楠瓜UID：2693754

10.5早听写

http://blog.sina.com.cn/s/blog_86290bae0100x6zv.html

Scientists investigating a popular herbal treatment for enlarge prostate have concluded that saw palmetto is no more effective than a placebo.

That conclusion comes from a study including hundreds of men in their forties and older. As men age, the prostate gland often gets larger. The prostate surrounds the urethra, which carries urine from the bladder to the penis. An enlarged prostate can impede the flow of urine, causing a variety of symptoms.
There are prescription drugs which can ease symptoms, but many men prefer the "natural" alternative, an extract from the saw palmetto tree, native to the American Southeast.
"It's actually a very complex extract? It has quite a number of different chemicals and molecules within it, several of which are plausible agents to affect the way a man urinates, to even shrink the prostate." Dr Gerald L. Andreiole of Washington university medical school in St. Louis, is one of co-authored a paper describing a new study on the effecitiveness of saw palmetto.
The men in the study were randomly assigned to two groups, one got progressively larger doses of saw palmetto, the other group got a placebo - a dummy pill. It was a double blind study, neither the participants nor staff knew who was getting which.
They filled out a standard questionnaire used by urologists to assess prostate enlargement. "How many times did you need to get up at night, how often did you experience frequency, urgency, the sense of incomplete bladder emptying. This is a standard symptom score that has been used for close to 20 years. "
By the end of the study after about 16 months, Andriole says the symptom scores improved for both groups of men. "But there was no difference in the magnitude of symptom score improvement between placebo and saw palmetto."
And increasing the dose of saw palmetto didn't make any difference. Some critics found fault with a previous study, that found no benefit from saw palmetto, saying the dosages were too low.
Saw palmetto is safe and thanks to the so called "placebo effect," it does improve symptoms, but Andriole says it doesn't address more serious prostate conditions. "Such as urinary tract infections, complete inability to urinate, or even the need to have surgery. The drugs we have significantly reduce a man's chance of ever experiencing those, in addition to improving his symptoms." Andriole says.
Since saw palmetto does not require a prescription, patients who use the herbal supplements might not see a doctor. That raises the risk that much more serious problems, like the early stages of prostate cancer might go undiagnosed.


prostate  n. (雄性哺乳动物的)前列腺
saw   n. 锯
palmetto   n. 美洲蒲葵(棕榈科植物)
placebo  n. 安慰剂；安慰物, 宽心话
gland  n. 〈解〉腺
urethra  n. 尿道
urine  n. 尿
urinary  adj. 尿的;尿样的；泌尿的;泌尿器的
urinate  vi. 排尿;撒尿
urologist   n. 泌尿科医师
bladder  n. 〈解〉膀胱
penis  n. 阴茎
extract  n. 提炼物, 浓缩物
molecule  n. 分子
plausible  adj. (声明、争论等)似乎是真的
agent   n. 原动力, 动因; 作用剂
affect  vt. 影响   effect  vt. 实现, 使生效, 引起
urinate  vi. 排尿;撒尿
co-author   n. 合著者
randomly   adv. 随便地,未加计划地
assign  vt. 指派, 选派
dummy  n. 仿制品
magnitude  n. 巨大; 重要性
critic  n. 批评家, 评论家
dosage  n. (按剂量的)给药
infection  n. 〈医〉传染, 感染
tract  n. 〈解〉道, 束

saw palmetto   锯棕榈(可改善前列腺肥大)
in addition to   除……之外

楠瓜UID：2693754

10.6早听写

http://blog.sina.com.cn/s/blog_86290bae0100x8zp.html

Pro:

So, are there any questions?


Stu:
Yes, Professor Harrison. You were saying that the periodic table is predictive? What exactly does that mean? I mean I understand how it organizes the elements but where's the prediction?


Pro:
Ok, let's look at our periodic table again. Ok, it groups elements into categories that share certain properties right?


Stu:
Um~huh~


Pro:
And it's ranged according to increasing atomic number, which is...?


Stu:
the number of protons in each atom of an element.


Pro:
Right, well early versions of the periodic table had gaps, missing elements. Every time you had one more proton, you had another element. And then oops, there have been atomic number for which there's no known element. And the prediction was that the element with that atomic number existed somewhere, but it just hadn't been found yet. And its location in the table would tell you what properties it should have. It was really pretty exciting for scientists at that time to find these missing elements and confirm their predictive properties. Um, actually that reminds me of a very good example of all these element 43. See on the table, the symbols for element 42 and 44. Well, in early versions of the table there was no symbol for element 43 protons, because no element with 43 protons had been discovered yet. So the periodic table had a gap between elements 42 and 44, and then in 1925 a team of chemists led by a scientist named Ida Tack claimed that they had found element 43. They had been using a relatively new technology called X-ray spectroscopy, and they were using this to examine an ore sample and they claimed that they'd found an element with 43 protons and they named it Masuria.


Stu:
Um, Proferssor Harrison, then how come in my periodic table here? Element 43 is TC, that's Technetium, right?


Pro:
Ok, let me add that. Actually, um, that's the point I'm coming to. Hardly anyone believed that Tack has discovered the new element. X-ray spectroscopy was a new method at that time. And they were never able to isolate enough Masuria to have available sample to convince everyone of the discovery. So they were discredited. But then 12 years later, in 1937, a differnt team became the first to synthesize the element using a cyclotron. And that element had...


Stu:
43 protons?


Pro:
That's right.
But they named it Technetium to emphasize that it was artificially created for technology and people thought that synthesizing this element, making it artificially was the only way to get it. We still haven't found it currently in nature. Now, element 43 what they called Masuria or Technetium is radioactive. Why is that matter? What's true of the radioactive element?


Stu:
It decays? it turns into other elements? Oh, so does that explain why it was missing in the periodic table?


Pro:
Exactly, because of its radioactive decay, element 43 doesn't last very long and therefore if it ever had been present on earth, it would have decayed ages ago. So, the Masuria people were obviously wrong and the Technetium people were right. Right? Well, that was then. Now we know that element 43 does occur naturally. It can be naturally generated from Uranium atom that has spontaneously split. And guess what, the ore sample the Masurium group was working with had plenty of Uranium in it, enough to split into measurable amounts of Masurium. So Tack's team might very well have found in small amounts of Masurium in the ore sample just that once it was generated from the Uranium, it decayed very quickly. And you know, here's an incredible irony. Ida Tack, the chemist led the Masurium team, when she was the first to suggest that Uranium could break up into smaller pieces, but she didn't know that that was the defense of her own discovery of element 43.


Stu:
So it's my version of the periodic table wrong should element 43 really be called Masurium?


Pro:
Maybe, but you know it's hard to tell for sure after all this time if Ida Tack's group didn't discovery element 43, they didn't, um publish enough detail on their methods or instruments for us to know for sure, but I'd like to think element 43 was discovered twice. As Masurium, it was the firsrt element discovered that occurs in nature only from spontaneous fission. And as Technetium, it was the firsrt element discovered in laboratory, and of course, it was an element the periodic table let us to expect existed before anyone had found it or made it.


proton  n. 质子
spectroscopy  n. 光谱学,波谱学,分光镜使用
technetium  n. 锝
synthesize  vt. 综合, 使合成
cyclotron  n. 回旋加速器
radioactive  adj. 放射性的
Uranium   n.铀
spontaneously  adv. 自然地;自发地;不由自主地
split  vt. & vi. (使)裂开; (使)破裂
measurable  adj. 可量度的, 可测量的, 可衡量的；明显的;重大的
fission  n. <物>(原子的)分裂, 裂变



that was then　 错误的曾经

楠瓜UID：2693754

10.7早听写

http://blog.sina.com.cn/s/blog_86290bae0100x9pr.html

listen to part of a lecture in an animal behavior class.



Pro:

Ok, well last time we talked about passive habitats selection like plants for example, they don't make active choices about where to grow. They are dispersed by some other agent like the wind and if the seeds land in a suitable habitat, they do well and reproduce. With active habitat selection, an organism is able to physically select where to live and breed. And because the animal's breeding habitate is so important, we expect animal species to develop preferences for particular types of habitats, places where their offspring has the best chance of survival. So let's look at the effect these preference can have by looking at some examples. But first let's recap. What do we mean by habitat? Frank?


Stu:
Well, it's basically the place or environment where an organism normally lives and grows.


Pro:
Right. And as we've discussed there're some key elements that habitats must contain, food obviously, water, and it's got to have the right climitate and its basis for physical protection. And we saw how important habitats selection is when we looked at habitats where some of these factors are removed. Perhaps, through habitats destruction. Um...I a just read about a short bird, the plover. The plover lives by the ocean and feeds on small shellfish, insects and plants. It blends in with the sands, so it's well camouflaged from predator birds above. But it lays its eggs in shallow depressions in the sand with very little protection around them. So if there're people or dogs on the beach, the eggs and fledglings(fledge) in the nest are really vulnerable. Outing California weather's been a lot of human development by the ocean. The plovers are now a threatened the species, so conservationists tried to create a new habitat for them. They made artificial beaches and sandbars in areas inaccessible to people and dogs, and the plover population is up quite a bit in those places.
Ok, that's an incidence where a habitat is made less suitable. But now, what about cases where an animal exhibits a clear choice between two suitable habitats in cases like that. Does the preference matter? Well let's look at the blue warbler.
The blue warbler is a songbird that lives in North America. They clearly prefer hardwood forests with dense shrubs, bushes underneath the trees. They actually nest in the shrubs, not the trees. So they are pretty close to the ground. But these warblers also nest in forests that have low shrub density. It's usually the younger warblers that nest in these areas because the preferred spots where there are a lot of shrubs are taken by the older, more dominant bird.
And the choice of habitats seems to affect the reproductive success, because the older, more experienced birds who nest in the high density shrub areas have significantly more offspring than those in low density areas, which suggest that the choice of where to nest does have impact on the number of chicks they have. But a preferred environment doesn't always seem to correlate with a greater reproductive success. For example, in Europe, studies have been done on blackcap warblers. We just call them blackcaps.
The blackcaps can be found in two different environments. Their preferred habitat is forests near the edges of streams. However, blackcaps also live in pine woods away from water. Studies have been done on the reproductive success rate for the birds in both areas and the result showed surprisingly that the reproductive success was essentially the same in both areas, the preferred the second choice habitat, well... why?
It turned out that there were actually 4 hour times as many bird pairs or couples living in the stream edge habitat compared to the area away from the stream, so this stream edge area had a much denser population, which meant more members of the same species competing for resources, wanting to feed on the same thing or build their nest in the same places, which lower the suitability of the prime habitat even though it's their preferred habitat. So the results of the study suggest that when the number of competitors in the prime habitat reaches a certain point, the second rank habitat becomes just as successful as the prime habitat, just because there are fewer members of the same species living there. So it looks like competition for resources is another important factor in determining if a particular habitat is suitable.


disperse  vt. & vi. (使)散开, 驱散
organism  n. 有机物, 有机体; 生物
breed  vt. & vi. 生育; 繁殖
survival  n. 幸存, 生存
recap  vt. & vi. 扼要重述;概括
camouflage  vt. & vi. 隐蔽；隐藏；掩藏；掩盖
depression  n. 凹陷, 洼地
vulnerable  adj. 易受伤的, 脆弱的, 敏感的
fledgling  n. (刚学会飞的)幼鸟    fledge   vi. (鸟)长羽毛
conservationist  n. 自然资源保护者,生态环境保护者
sandbar  n. 沙洲
inaccessible  adj. 达不到的, 不可及的
incidence  n. 发生率, 影响范围
hardwood  n. 硬(木)材;硬木树;阔叶树
shrub  n. 灌木
underneath   prep. 在…下面; 在…底下
correlate  vt. & vi. 有相关性
essentially  adv. 本质上;根本上
dense  adj. 密集的, 稠密的, 浓密的
preferred  adj. 首选的


chick  n. 小鸡,小鸟,幼雏
warbler  n. 鸣鸟,用颤音歌唱的人
plover  n. 珩,珩科鸟(如凤头麦鸡)
blackcap   n. (欧洲产的)莺类,白颊鸟类