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1、共生：Amphipod H.D.背海蝴蝶
【段落大意】
第一段：
有一种Amphipod Hyperiella dilatata(片脚类动物,类似shrimp)会背着sea butterfly跑，这样在一起不容易被捕食。专家认为背着这种海蝴蝶会减缓Amphipod H.D 移动的速度，并且vulnerable to predation(Q)。
第二段：
一个科学家做了一个实验，把HD的捕食者和HD及sea butterfly放在一起，结果捕食者不敢吃HD。实验结论是sea butterfly会释放一种chemical，所以捕食者就不敢吃HD了。将HD的行为和decorator crab做比较，但与AH.D不同的是，crab不是特定的捕食某种物质，而是捕食随手能及的东西。专家研究后认为，AH.D其实是一种利他无私行为，就是利他损已。
第三段：
这个现象和之前发现的symbiosis共生的3种分类都不符合，然后进行解释。讲这两个shrimp和sea butterfly的关系，列出了3种分类 symbiosis:分别是Mutualism，Commensalism, Parasitism【M互利共生、C片利共生 or共栖(互相不干扰)、P寄生共生】，然后给出一个新的分类new category叫 antagonistic symbiosis对抗性共生。最后得出结论:只有shrimp受益，所以很Unique。然后说其实也不一定会对H.D有害，因为他们都背着活的而不是死的海蝴蝶，这说明他们是有选择的/or科学家发现那个生物从来不会带着死掉的海蝴蝶跑,所以估计那个生物应该都是抓活的海蝴蝶。
【题目】
Q1: 主旨题
Q2: 细节题：问Amphipod HD动物这种行为会使自己产生什么后果?
Q3: infer题：如果H.d和海蝴蝶不是第1或第2种symbolisis，能得出什么?
Q4: 第三段的function?
【参考阅读】
The nature of this relationship is puzzling. It is difficult to discern how
carrying another organism around can be advantageous. We speculated that in fact, amphipods片脚类动物must be considerably slowed down. By carefully measuring the swimming speeds of amphipods with and without seabutterflies, we found that amphipods carrying seabutterflies moved only half as quickly as similarly sized solitary amphipods. The situation simply made nosense. In reducing their mobility, the amphipods became more vulnerable to predators and less adept at capturing prey. Why, then, would amphipods go out of their way to abduct诱拐 and carry sea butterflies?
Our experiments clearly demonstrated that something about the sea butterflies was repelling the fish, and we suspected that this deterrence威慑was chemical. To find out, we conducted a second set of feeding experiments. We homogenized均匀分布、均质化the sea butterflies and mixed the homogenate [组织]匀浆with fish-meal powder to make food pellets小弹丸. As a control, we also made food pellets containing just the fish-meal powder. We offered both the experimental and the control pellets to fish, which always ate the control pellets and always rejected the pellets containing the homogenate. This provided compelling evidence that compounds might be responsible for the feeding chemical deterrence.【证明是海蝴蝶有chemical可以吓退吃HD的鱼】
Our experiments demonstrated to us that the sea butterfly C. Antarctica synthesizes a deterrent威慑作用的 substance that the exploits for its own protection. This - the abduction of one species by another - is unprecedented in the annals of behavioral and chemical ecology. Some decorator crabs are chemical ecology known to cover their upper carapace甲壳 with a variety of objects, including the occasional sponge that might harbor defensive chemistry. But this appears to be a nonselective behavior. Crabs haphazardly decorate themselveswith whatever is at hand.
The association between the sea butterfly and the amphipod falls within the definition of symbiosis共生, where two dissimilar species live together in an
intimate association.
Parasitism寄生 implies that one species associates with another to the detriment伤害of one of them. Often, the parasite feeds off the tissues or body fluids of its host.
Mutualism互利共生 describes a relationship where both species benefit from the association.
Commensalism共栖 describes organisms that live in benign and neutral中立or良性 association with one another. Neither of the latter two interactions appropriately describes what we have observed, and parasitism寄生 provides only a very weak analogy to it. We feel that a new term might be needed to describe the "antagonistic symbiosis" that seems to describe most accurately this unique interaction.
parasitism寄生:一个伤害另一个,吃对方组织和体液。
mutualism互利共生:双方都获利。
commensalism共栖:中立,互相不干扰。 实际(如果加上下一段的文章):一个获利,另一个间接受害, 若没有下面这段,得看选项怎么说了.
2、地震
In most earthquakes the Earth’scrust cracks like porcelain, Stress buildsup until a fracture forms at a depth of a few kilometers and the crust (5)slips to relieve the stress. Some earthquakes, however, take place hundreds ofkilometers down in the Earth’s mantle, where high pressure makes rock soductile that it flows instead of (10) cracking, even under stress severe enoughto deform it like putty.How can there be earthquakes at such depths? That such deep events do occur hasbeen accepted only since 1927 when the seismologist Kiyoo Wadati convincinglydemonstrated their existence. Instead of comparing the arrival times of seismicwaves at different locations, as earlier researchers had done, Wadati relied ona time difference between the arrival of primary(P) waves and the slowersecondary(S) waves. Because P and S waves travel at different but fairlyconstant speeds, the interval between their arrivals increases in proportion tothe distance from the earthquake focus, or initial rupture point.
For most earthquakes, Wadatidiscovered, the interval was quite short near the epicenter; the point on thesurface where shaking is strongest. For a few events, however, the delay waslong even at the epicenter. Wadati saw a similar pattern when he analyzed dataon the intensity of shaking. Most earthquakes had a small area of intenseshaking, which weakened rapidly with increasing distance from the epicenter,but others were characterized by a lower peak intensity, felt over a broaderarea. Both the P-S intervals and the intensity patterns suggested two kinds ofearthquakes: the more common shallow events, in which the focus lay just underthe epicenter, and deep events, with a focus several hundred kilometers down.
The question remained: how can suchquakes occur, given that mantle rock at a depth of more than 50 kilometers istoo ductile to store enough stress to fracture? Wadati’s work suggested thatdeep events occur in areas (now called Wadati-Benioff zones) where one crustalplate is forced under another and descends into the mantle. The descending rockis substantially cooler than the surrounding mantle and hence is less ductileand much more liable to fracture.
GWD-24-30.
The author’s explanation of how deepevents occur would be most weakened if which of the following were discoveredto be true?
A. Deep events are far less common thanshallow events.
B. Deep events occur in places other than where crustal plates meet.
C. Mantle rock is more ductile at adepth of several hundred kilometers than it is at 50 kilometers.
D. The speeds of both P and S waves areslightly greater than previously thought.
E. Below 650 kilometers earthquakescease to occur.
GWD-24-31.
Information presented in the passagesuggests that, compared with seismic activity at the epicenter of a shallowevent, seismic activity at the epicenter of a deep event is characterized by
A. shorter P-S intervals and higherpeak intensity
B. shorter P-S intervals and lower peakintensity
C. longer P-S intervals and similarpeak intensity
D. longer P-S intervals and higher peakintensity
E. longer P-S intervals and lower peakintensity.
GWD-24-32.
The passage supports which of thefollowing statements about the relationship between the epicenter and the focusof an earthquake?
A. P waves originate at the focus and Swaves originate at the epicenter.
B. In deep events the epicenter and thefocus are reversed.
C. In shallow events the epicenter andthe focus coincide
D. In both deep and shallow events thefocus lies beneath the epicenter
E. The epicenter is in the crust,whereas the focus is in the mantle.
GWD-24-33.
The passage suggests that which ofthe following must take place in order for any earthquake to occur?
1. Stress must build up.
2. Cool rock must descend into themantle.
3. A fracture must occur
A. 1 only
B. 2 only
C. 3 only
D. 1 and 3 only
E. 1, 2, and 3
Q34：The passage is primarily concerned with
A. demonstrating why the methods ofearly seismologists were flawed
B. arguing that deep events are poorly understood and deserve further study
C. defending a revolutionary theory about the causes of earthquakes and methods of predicting them
D. discussing evidence for the existence of deep events and the conditions that allow them to occur
E. comparing the effects of shallowevents with those of deep events
Q35：The author uses the comparisons toporcelain and putty in order to
A. explain why the Earth’s mantle isunder great pressure
B. distinguish the earthquake’sepicenter from its focus
C. demonstrate the conditions underwhich a Wadati-Benioff zone forms
D. explain why S waves are slower thanP waves
E. illustrate why the crust willfracture but the mantle will not
Q36：It can be inferred from the passage that if the S wavesfrom an earthquake arrive at a given location long after the P waves, which ofthe following must be true?
A. The earthquake was a deep event.
B. The earthquake was a shallow event.
C. The earthquake focus was distant.
D. The earthquake focus was nearby.
E. The earthquake had a low peak intensity.
Q37：The method used by Wadati to determine the depths ofearthquakes is most like which of the following?
A. Determining the depth of a well bydropping stones into the well and timing how long they take to reach the bottom
B. Determining the height of a mountainby measuring the shadow it casts at different times of the day
C. Determining the distance from athunderstorm by timing the interval between the flash of a lightning bolt andthe thunder it produces
D. Determiningthe distance between two points by counting the number of paces it takes tocover the distance and measuring a single pace
E. Determining the speed at which a caris traveling by timing how long it takes to travel a known distance