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候鸟
V1P1鸟的迁徙辨认方向的因素，一个是by什么，另一个是by environmental cues.然后讲这个cues包括什么东西啊，比如什么。然后举了个例子，说一个人的研究，鸟儿是根据太阳来到达目的地的，however，in spring and autum,怎样怎样（忘记了）然后这个人通过镜子改变阳光照射进屋子的角度，到达什么效果（忘了）
P2 但是太阳的位置是变化的啊，鸟儿会不会受影响呢，这段不长
V2(760).
第四篇：【狗狗第19篇】：鸟类迁徙。这个应该是高分题。JJ里面很详细了。2段。
P1: Unlike nonmigratory birds, migratory bids要迁徙。受2个cues影响。1个是森林树木等地理方位的。1个是刮风类。然后做了个study，发现鸟是根据太阳到目的地的，balabala...
P2: 有人疑问，那为啥鸟在一天之内是咋办的呢？一天之内太阳一直在动吖~回答：自己的生物钟。
考题：1. Main idea考题有一道主旨题，我选的提出一种观点和他的flaw
2.第二段说鸟在一天之内太阳一直动它咋办的呢？（选rhythmic）
3.第二段的作用
1.有个问题问第二段的作用，答案是第二段提出了第一段没有考虑到的一个情况或者问题
考古
版本3
"Q1通过镜子的实验证明了什么？我选证明了候鸟飞行方向是受太阳影响的；还有一个选项是证明候鸟飞行方向受一些CLUE的影响,但定位（第一段）以后发现这些CLUE指的是太阳以外，别的对候鸟飞行方向有影响的东西（比如forest、潮汐什么的）。Q2问第二段的作用。（第二段讲的是太阳方向不能完全解释候鸟飞行方向，可能有生物钟内部调控）选项有一个是说明第一段做实验的那个人fail to consider什么,另一个是讲由第一段的research引出的问题。我选后面那个。Q3主题题？
记不清了第二段功能（提出此学者没有考虑的情况）/ 此试验证明了什么"
关于不靠磁场辨认方向的鸟类根据太阳辨别方向的题
[版本4]问题会问到作者可能赞成的观点.文中提到有人做了实验,用镜子反射阳光,鸟就会冲反射的方向飞.但是后面一段对实验结果的结实提出了疑问.说每天太阳的位置都是变化的,鸟儿怎么辨别呢?问题中有问这一段的作用,答带"question"的就对了.
[版本5]（45行）候鸟迁徙靠什么指引方向，有人做了实验，认为是靠太阳。作者也基本认可，但第二段说太阳在一天内的方位不同，这引起了理论的漏洞。估计可能是鸟的体内有调节器。
鸟类迁徙的那个正确，但是JJ那些描述的貌似是下半部分前面是怎么引出的没写---回忆者写26.候鸟辨方向 非考古考古- -。
请考到候鸟辨方向的同学来看一下~~~~这篇是TPO里的，感觉和狗狗还蛮像的。。
Orientation and Navigation
To South Americans, robins are birds that fly north every spring. To North Americans, the robins simply vacation in the south each winter. Furthermore, they fly to very specific places in South America and will often come back to the same trees in North American yards the following spring. The question is not why they would leave the cold of winter so much as how they find their way around. The question perplexed people for years, until, in the 1950s, a German scientist named Gustave Kramer provided some answers and. in the process, raised new questions.
Kramer initiated important new kinds of research regarding how animals orient and navigate. Orientation is simply facing in the right direction; navigation involves finding ones way from point A to point B.
Early in his research, Kramer found that caged migratory birds became very restless at about the time they would normally have begun migration in the wild. Furthermore, he noticed that as they fluttered around in the cage, they often launched themselves in the direction of their normal migratory route. He then set up experiments with caged starlings and found that their orientation was. in fact, in the proper migratory direction except when the sky was overcast, at which times there was no clear direction to their restless movements. Kramer surmised, therefore, that they were orienting according to the position of the Sun. To test this idea, he blocked their view of the Sun and used mirrors to change its apparent position. He found that under these circumstances, the birds oriented with respect to the new "Sun." They seemed to be using the Sun as a compass to determine direction. At the time, this idea seemed preposterous How could a bird navigate by the Sun when some of us lose our way with road maps? Obviously, more testing was in order.
So, in another set of experiments, Kramer put identical food boxes around the cage, with food in only one of the boxes. The boxes were stationary, and the one containing food was always at the same point of the compass. However, its position with respect to the surroundings could be changed by revolving either the inner cage containing the birds or the outer walls, which served as the background. As long as the birds could see the Sun, no matter how their surroundings were altered, they went directly to the correct food box. Whether the box appeared in front of the right wall or the left wall, they showed no signs of confusion. On overcast days, however, the birds were disoriented and had trouble locating their food box.
In experimenting with artificial suns, Kramer made another interesting discovery. If the artificial Sun remained stationary, the birds would shift their direction with respect to it at a rate of about 15 degrees per hour, the Sun's rate of movement across the sky. Apparently, the birds were assuming that the "Sun" they saw was moving at that rate. When the real Sun was visible, however, the birds maintained a constant direction as it moved across the sky. In other words, they were able to compensate for the Sun's movement. This meant that some sort of biological clock was operating-and a very precise clock at that.
What about birds that migrate at night? Perhaps they navigate by the night sky. To test the idea, caged night-migrating birds were placed on the floor of a planetarium during their migratory period. A planetarium is essentially a theater with a domelike ceiling onto which a night sky can be projected for anynight of the year. When the planetarium sky matched the sky outside, the birds fluttered in the direction of their normal migration. But when the dome was rotated, the birds changed their direction to match the artificial sky. The results clearly indicated that the birds were orienting according to the stars.
There is accumulating evidence indicating that birds navigate by using a wide variety of environmental cues. Other areas under investigation include magnetism, landmarks, coastlines, sonar, and even smells. The studies are complicated by the fact that the data are sometimes contradictory and the mechanismsapparently change from time to time. Furthermore, one sensory ability may back up another.
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发表于 2012-6-14 12:24:49
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