Eventually, their front limbs became flippers and their hind limbs became weak and unnecessary.

最终，它们的前肢变成了鳍状肢，而它们的后肢变得虚弱和多余。

Thor's lizards developed stronger front legs and smaller back legs, allowing them to cling on, hold on to something tightly, when hurricanes pass through.

索尔所说的蜥蜴发展出更强壮的前肢和更小的后肢，让它们在飓风经过时可以紧紧抓住某些东西。

And they were almost right. Longer front legs and larger toe pads indeed helped.

他们的想法基本上对的。前肢更长、趾垫更大确实有帮助。

It affected the young animal's front legs, which became hyperextended.

影响了幼崽的前肢，使前肢腕关节过度伸展。

Early in the rotation, the cat pulls its front legs in and leaves the back splayed out so the front half can rotate quickly while the back half stays relatively still.

在旋转的早期，猫把前腿拉进去，让后肢张开，样前肢可以快速旋转，而后肢保持相对静止。

We call them wings, and the birds use them for flying.

我们管鸟的前肢叫" 翅膀" ，鸟用翅膀来飞翔的。

Powerful forelegs enable it to rip apart a termite hill with ease.

有力的前肢让它们能够轻易地掰开白蚁巢。

They have to do essentially a super push-up with their powerful forelimbs, the strongest limbs they have, get up high enough so that they can get their wings to flap and get off the ground.

必须靠最有力的前肢将身体用力向上推到达足够的高度以伸展翅膀平地起飞。

Basically that means they're just spreading out on a surface on their stomach, with their forelimbs forward and their hind legs backwards, just kind of splat on the ground.

基本上，也说，它们展开身体，将腹部贴在地上，前肢向前，后腿向后，像拍在地上一样。

By retracting its legs and inflating its front body segment this caterpillar resembles the head of a snake complete with scales and eye-like spots.

条毛毛虫缩回双腿，膨胀前肢，形似一个蛇头，布满了鳞片还有像眼睛一样的斑点。

You see, it is hard for bears to run down hill, because their hind legs are longer than their front ones.

你知道的，熊很难跑下山，因为它们的后肢比前肢长得多。

Like, when primates and squirrels get more practice using their forelimbs to climb trees, that can favor a bigger cerebellum.

比如，当灵长类动物和松鼠用它们的前肢爬树得到更多的练习时，会有更大的小脑。

It's called a ballistic launch, so they can use the power from there, like ligaments and muscles, to push off the ground using their forelimbs.

被称为弹道发射，所以它们可以利用韧带和肌肉的力量、利用它们的前肢离开地面。

She has long, strong front legs to help her climb around for food 20 metres up in the canopy.

它的前肢又长又有力，可以帮助它在 20 米高的树冠上四处攀爬觅食。

Led by his super sensitive nose, his long limbs carry him many miles a day in search of carrion.

凭借极度敏感的嗅觉和长长的前肢，短面熊为了寻找腐肉能一天行进数英里。

Whereas with pterosaurs, with this strategy, you're focusing it into one area and really use it both ways.

所以，翼龙的飞行只会使用到前肢。

Technically, two-toed sloths should be really called two-fingered sloths because the difference is only their front limbs.

从技术上讲，二趾树懒应该被称为二指树懒，因为它们的区别只前肢。

And so it could reach out and smack things with those long arms if it needed to.

如果有必要它们能够伸出长长的前肢猛击目标。

Its powerful arm muscles are composed of 80% fast-twitch fiber, a third more than humans.

它强壮的前肢肌肉中百分之八十快缩肌纤维，比人类的多三分之一。

They're almost the size of T-Rex's arm in terms of length.

它们的前肢长度几乎与霸王龙的一样。