2017年9月9日的考試真題解析已經(jīng)出來了，口語考試題目有哪些呢?出國留學網(wǎng)托福欄目小編整理了相關的資料，希望可以幫助考生度過考試的難關，下面是小編搜集的托?？谡Z真題解析相關資訊，歡迎參考!
新托?？谡ZTask4題目回憶版本一:
Reading
natal homing，動物成年之后回到自己出生的地方進行繁殖
Listening
green sea turtle回到出生地繁殖因為溫度合適且沒有天敵
新托福口語Task4題目回憶版本二:
Task 4 閱讀 標題：natal homing
定義：一些特殊物種在繁殖的時候會回到自己的原棲息地尋求更佳適合的條件。
聽力例子：舉出一種綠色海龜，在繁殖產(chǎn)卵的時候就會回到原來的棲息地海灘，因為溫度更適合，而且能夠有效抵御天敵攻擊，保護幼崽等。
新托?？谡ZTask4題目回憶版本三:
natal homing:一些特殊物種在繁殖的時候會回到自己的原棲息地尋求更佳適合的條件。
舉出一種綠色海龜，在繁殖產(chǎn)卵的時候就會回到原來的棲息地海灘，因為溫度更適合，而且能夠有效抵御天敵攻擊，保護幼崽等。
新托?？谡ZTask4知識補充;
Natal homing, or natal philopatry, is the homing process by which some adult animals return to their birthplace to reproduce. This process is primarily used by aquatic animals, such as sea turtles and Pacific salmon. Scientists believe that the main cues used by the animals are geomagnetic imprinting and olfactory cues. The benefits of returning to the precise location of an animal's birth may be largely associated with its safety and suitability as a breeding ground. When seabirds, like the Atlantic puffin, return to their natal breeding colony, which are mostly on islands, they are assured of a suitable climate and a sufficient lack of land-based predators.
Sea turtles born in any one area differ genetically from turtles born in other areas. The newly hatched young head out to sea and soon find suitable feeding grounds, and it has been shown that it is to these feeding areas that they return rather than to the actual beach on which they started life. Salmon start their lives in freshwater streams and eventually travel down-river and are washed out to sea. Their ability to travel back, several years later, to the river system in which they were spawned is thought to be linked to olfactory cues, the "taste" of the water. Atlantic bluefin tuna spawn on both the east and west shores of the Atlantic Ocean but intermingle as they feed in mid-ocean. Juvenile tuna that have been tagged have clearly shown that they almost invariably return to the side of the Atlantic on which they were spawned.
Various theories have been put forward as to how the animals find their way home. The geomagnetic imprinting hypothesis holds that they are imprinted with the unique magnetic field that exists in their natal area. This is a plausible theory but has not been proven to occur. Pacific salmon are known to be imprinted on the water chemistry of their home river, a fact that has been confirmed experimentally. They may use geomagnetic information to get close to the coast and then pick up the olfactory cues. Some animals may make navigational errors and end up in the wrong location. If they successfully breed in these new sites, the animal will have widened its breeding base which may ultimately increase the species' chances of survival. Other, unknown means of navigation may be involved, and further research is needed.
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