托福阅读素材:饵料鱼
2017-09-20编辑: 环球教育整理来自: 环球教育
很多考生会抱怨托福阅读时间不够,还没完全理解文章就做题,正确率不高。其实这是我们对托福阅读素材不熟悉造成的,下面小编整理了一下托福阅读考试最新的素材,希望能帮助大家更加快速高效的备考托福。
托福阅读素材:饵料鱼
文章讲述了prey fish.文章共六段,第一段讲鱼有很多方法来躲避被捕食到。有主动和被动的方法。主动的方法如逃跑;被动的方法如结构上的特点。第二段和第三段讲到鱼成群地游泳来躲避捕食者。根据捕食者的体型等特点,遇到捕食者时,它们会分散开来。第四段和第五段讲到捕食者们因为各种原因也有抓不到鱼的情况,他们一般会抓捕大群中掉队的鱼。第六段讲捕食者和鱼之间的 Capture And Anti-capture 活动。
参考阅读:
Forage fish, also called prey fish or bait fish, are small pelagic fish which are preyed on by larger predators for food. Predators include other larger fish, seabirds and marine mammals. Typical ocean forage fish feed near the base of the food chain on plankton, often by filter feeding. They include particularly fishes of the family Clupeidae (herrings, sardines, shad, hilsa, menhaden, anchovies and sprats), but also other small fish, including halfbeaks, silversides, smelt such as capelin, and the goldband fusiliers pictured on the right.
Forage fish compensate for their small size by forming schools. Some swim in synchronised grids with their mouths open so they can efficiently filter plankton.[1] These schools can become immense shoals which move along coastlines and migrate across open oceans. The shoals are concentrated fuel resources for the great marine predators. The predators are keenly focused on the shoals, acutely aware of their numbers and whereabouts, and make migrations themselves that can span thousands of miles to connect, or stay connected, with them.[2]
The ocean primary producers, mainly contained in plankton, produce food energy from the sun and are the raw fuel for the ocean food webs. Forage fish transfer this energy by eating the plankton and becoming food themselves for the top predators. In this way, forage fish occupy the central positions in ocean and lake food webs.[3]
The fishing industry catches forage fish primarily for feeding to farmed animals. Some fisheries scientists are expressing concern that this will affect the populations of predator fish that depend on them.[4] ypical ocean forage fish are small, silvery schooling oily fish such as herring, anchovies and menhaden, and other small, schooling baitfish like capelin, smelts, sand lance, halfbeaks, pollock, butterfish and juvenile rockfish. Herrings are a preeminent forage fish, often marketed as sardines or pilchards.
The term “forage fish” is a term used in fisheries, and is applied also to forage species that are not true fish, but play a significant role as prey for predators. Thus invertebrates such as squid and shrimp are also referred to as "forage fish". Even the tiny shrimp-like creatures called krill, small enough to be eaten by other forage fish, yet large enough to eat the same zooplankton as forage fish, are often classified as "forage fish". Forage fish utilise the biomass of copepods, mysids and krill in the pelagic zone to become the dominant converters of the enormous ocean production of zooplankton. They are, in turn, central prey items for higher trophic levels. Forage fish may have achieved their dominance because of the way they live in huge, and often extremely fast cruising schools.
Though forage fish are abundant, there are relatively few species. There are more species of primary producers and apex predators in the ocean than there are forage fish.[2]
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