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语音：美式发音
适合精听语速：200词/分钟
关键词：fish，land-walking，adapt
鱼类的起源和进化在生物发展史上具有十分重要的意义。鱼类的出现标志着无脊椎动物向脊椎动物进化的一个质的飞跃，其发展及演化提供了动物进化的谱系。在多种古代鱼类当中，其中一种与脊椎动物进化历程关系最密切的品种，便是古总鳍鱼。它们生活在泥盆纪时代，距今约三亿五千万年，当时陆地面积扩大，有明显的季节性变化及周期性干旱，这种鱼类被迫另找水源，长期的陆地“划行”使得适于水中游泳的鳍变成了适于陆地爬行的四肢。
鱼石螈是已知最早的两栖类动物，化石发现于格陵兰泥盆纪晚期的地层中，是脊椎动物从水到陆过渡阶段的代表。其脊椎构造比起总鳍鱼类有所进步，肢体已是早期两栖类的模样，能初步支撑身体在陆地上活动。
Taking a fish out of water—it’s an expression that describes something that literally shouldn’t work.But for some scientists，it apparently has.
This is the Senegal 1）Bichir...and it’s walking.Researchers took the fish from a young age and forced them to live on land for eight months，in conditions that were humid enough that they could survive.
“让鱼儿离开水”这句话表示某事行不通。不过对于一些科学家来说，这却是可以做到的。
这条是塞内加尔多鳍鱼……而它正在爬行。研究人员将鱼苗从幼体开始培育，在一个湿度足以让它们存活的环境中强迫这种鱼在陆地上生活了八个月。
The study found the fish—which were previously known to move on land only 2）incidentally—could adapt to walking on land.Basically，what the study wanted to look at was how 3）tetrapods—four-legged creatures—first pulled themselves out of the water and made that “Little Mermaid” switch from 4）aquatic animals to 5）terrestrial ones.
There are well-documented cases of fish—like the 6）mudskipper—walking on land and even climbing trees.But unlike the mudskipper the bichir has lungs，and crucially，as the study found，their movement on land is much closer to that of the earliest tetrapods.
Now that’s due to a number of factors，including the positioning of their fins on their body，but one of the really interesting things the study 7）charted was how the fishes’ bodies adapted to life on land.
Scientists looked at the 8）clavicle and a couple other bones that link the bichir’s head to its body.They found the clavicle and one of the other bones changed significantly in the land-walking fish，adapting to accommodate its new motions.
Those findings show the fish’s anatomical plasticity—its ability to change and adapt its body，a trait that would’ve been crucial for the first fish to walk on land.
The study has also raised some more profound philosophical questions，like “If a fish could walk，would it still be a fish？” Well，the scientists who conducted the study don’t really have an answer for that particular question，yet.
研究发现，这种早前所知仅在偶然情况才会爬上岸的鱼可以适应陆上行走。这一研究的主要目的在于探讨四足动物当初是怎样离开水域并完成“小美人鱼”的华丽转变，从水生走向陆生的。
早有充分资料表明，有些像弹涂鱼这样的鱼类可以在陆地爬行甚至能爬树。但与弹涂鱼不同的是，多鳍鱼体内长有肺部。该研究还发现了至关重要的一点：它们在陆地上的爬行方式更接近于最早期的四足动物。
造成这一现象的因素有很多，包括它们身上鱼鳍所处的部位；不过，在这项研究的记录当中，其中一个非常有趣的地方就是多鳍鱼的身体结构是如何适应陆地生活的。
科学家们对连接多鳍鱼头部及其身体的锁骨与另外两块骨骼进行研究。他们发现这种陆行鱼的锁骨与其中一块骨头发生了显著变化，以更好地适应新的运动方式。
这一系列研究结果体现了鱼类在结构上的可塑性，即这种改变身体结构以适应环境的能力，这正是第一代陆行鱼的关键特征。
此项研究还引发了一些更加深远的哲学问题，比如：“如果一条鱼可以爬行，它还算是鱼吗？”这个嘛，参与这次研究的科学家们对这个问题还没得出答案。
适合精听语速：200词/分钟
关键词：fish，land-walking，adapt
鱼类的起源和进化在生物发展史上具有十分重要的意义。鱼类的出现标志着无脊椎动物向脊椎动物进化的一个质的飞跃，其发展及演化提供了动物进化的谱系。在多种古代鱼类当中，其中一种与脊椎动物进化历程关系最密切的品种，便是古总鳍鱼。它们生活在泥盆纪时代，距今约三亿五千万年，当时陆地面积扩大，有明显的季节性变化及周期性干旱，这种鱼类被迫另找水源，长期的陆地“划行”使得适于水中游泳的鳍变成了适于陆地爬行的四肢。
鱼石螈是已知最早的两栖类动物，化石发现于格陵兰泥盆纪晚期的地层中，是脊椎动物从水到陆过渡阶段的代表。其脊椎构造比起总鳍鱼类有所进步，肢体已是早期两栖类的模样，能初步支撑身体在陆地上活动。
Taking a fish out of water—it’s an expression that describes something that literally shouldn’t work.But for some scientists，it apparently has.
This is the Senegal 1）Bichir...and it’s walking.Researchers took the fish from a young age and forced them to live on land for eight months，in conditions that were humid enough that they could survive.
“让鱼儿离开水”这句话表示某事行不通。不过对于一些科学家来说，这却是可以做到的。
这条是塞内加尔多鳍鱼……而它正在爬行。研究人员将鱼苗从幼体开始培育，在一个湿度足以让它们存活的环境中强迫这种鱼在陆地上生活了八个月。
The study found the fish—which were previously known to move on land only 2）incidentally—could adapt to walking on land.Basically，what the study wanted to look at was how 3）tetrapods—four-legged creatures—first pulled themselves out of the water and made that “Little Mermaid” switch from 4）aquatic animals to 5）terrestrial ones.
There are well-documented cases of fish—like the 6）mudskipper—walking on land and even climbing trees.But unlike the mudskipper the bichir has lungs，and crucially，as the study found，their movement on land is much closer to that of the earliest tetrapods.
Now that’s due to a number of factors，including the positioning of their fins on their body，but one of the really interesting things the study 7）charted was how the fishes’ bodies adapted to life on land.
Scientists looked at the 8）clavicle and a couple other bones that link the bichir’s head to its body.They found the clavicle and one of the other bones changed significantly in the land-walking fish，adapting to accommodate its new motions.
Those findings show the fish’s anatomical plasticity—its ability to change and adapt its body，a trait that would’ve been crucial for the first fish to walk on land.
The study has also raised some more profound philosophical questions，like “If a fish could walk，would it still be a fish？” Well，the scientists who conducted the study don’t really have an answer for that particular question，yet.
研究发现，这种早前所知仅在偶然情况才会爬上岸的鱼可以适应陆上行走。这一研究的主要目的在于探讨四足动物当初是怎样离开水域并完成“小美人鱼”的华丽转变，从水生走向陆生的。
早有充分资料表明，有些像弹涂鱼这样的鱼类可以在陆地爬行甚至能爬树。但与弹涂鱼不同的是，多鳍鱼体内长有肺部。该研究还发现了至关重要的一点：它们在陆地上的爬行方式更接近于最早期的四足动物。
造成这一现象的因素有很多，包括它们身上鱼鳍所处的部位；不过，在这项研究的记录当中，其中一个非常有趣的地方就是多鳍鱼的身体结构是如何适应陆地生活的。
科学家们对连接多鳍鱼头部及其身体的锁骨与另外两块骨骼进行研究。他们发现这种陆行鱼的锁骨与其中一块骨头发生了显著变化，以更好地适应新的运动方式。
这一系列研究结果体现了鱼类在结构上的可塑性，即这种改变身体结构以适应环境的能力，这正是第一代陆行鱼的关键特征。
此项研究还引发了一些更加深远的哲学问题，比如：“如果一条鱼可以爬行，它还算是鱼吗？”这个嘛，参与这次研究的科学家们对这个问题还没得出答案。