5 Mammals of the Trees-Mid

Mammals of the Trees FOCUS Question What do mammals that live in trees have in common?

生活在树上的哺乳动物有什么共同之处?

Look Up! You step across the shadowy jungle floor. A whistling call rings from the branches above. You look for the bird that made the sound. Instead, you spot a large, furry mammal swinging from branch to branch. You just saw a gibbon—a type of ape. A gibbon is an arboreal (ar-BOR-e-ul), or tree-dwelling, mammal. Many different kinds of mammals make their homes in trees. Living in high habitats has made these animals similar in many ways.

查找!你踏过阴暗的丛林地面。 头顶的树枝上响起了一阵呼啸声。 你寻找发出声音的鸟。 相反，你看到一只巨大的毛茸茸的哺乳动物在树枝间荡来荡去。 你刚才看到的是长臂猿，一种猿类。 长臂猿是一种树栖哺乳动物。 许多不同种类的哺乳动物在树上筑巢。 生活在高栖息地使得这些动物在很多方面都很相似。

Life in the Trees Living in trees has advantages. The biggest benefit is food. Monkeys eat a lot of fruit. Koalas eat leaves. These foods, along with insects and flower nectar, are plentiful in treetops. In trees, animals can avoid predators that only live on the ground. Many predators can't reach the treetops. Trees also have many nooks and crannies for hiding. Living in trees has its challenges, too. The biggest problem is moving from place to place without going down to the ground. Tree-dwelling mammals have to climb, swing or leap from branch to branch. Luckily, their bodies have features to help them get around.

生活在树上有很多好处。 最大的好处是食物。 猴子吃很多水果。 考拉吃树叶。这些食物，还有昆虫和花蜜，在树梢上非常丰富。 在树上，动物可以躲避只生活在地面上的捕食者。 许多捕食者够不到树顶。 树木也有许多藏身的角落和缝隙。 生活在树上也有它的挑战。 最大的问题是从一个地方移动到另一个地方，而不需要回到地面。 栖息在树上的哺乳动物必须在树枝间攀爬、摇摆或跳跃。 幸运的是，它们的身体有帮助它们四处走动的特征。

Primates A group of mammals called primates includes monkeys, lemurs, and apes. These animals eat insects, nuts, leaves, and a lot of fruit. How do arboreal primates get to these? treetop treats Most monkeys are small, so they can travel on the thinnest branches. They have strong, flexible arms that allow them to reach and swing. Thumbs on their hands and feet help them grab and hang on. Most monkeys have long tails to help them balance. Some even have prehensile tails, which can bend and grip like an extra hand. Think About It Humans are also primates. Do people have features that would allow us to live in trees?

灵长类动物是一种哺乳动物，包括猴子、狐猴和猿。 这些动物吃昆虫、坚果、树叶和许多水果。 树栖灵长类动物是如何做到这些的? 大多数猴子都很小，所以它们可以在最细的树枝上旅行。 它们有强壮而灵活的手臂，使它们能够伸展和摆动。 手和脚上的拇指帮助它们抓取和悬挂。 大多数猴子都有长尾巴来帮助它们保持平衡。 有些甚至有卷曲的尾巴，可以弯曲和抓握，就像一只额外的手。 人类也是灵长类动物。 人类是否具有能让我们生活在树上的特征?

Lemurs also have thumbs that can grip. Many lemurs have strong legs and feet that they use to "bounce" from trunk to trunk. Apes tend to be larger than monkeys and lemurs. Even with their large bodies, orangutans are arboreal. These great apes have long flexible arms and four thumbs used for climbing. All primates have eyes that face straight forward. This gives them binocular, or 3-D vision which helps them judge distances. It makes leaping from branch to branch much easier!

狐猴也有可以抓握的拇指。 许多狐猴有强壮的腿和脚，它们用来在树干之间“弹跳”。 猿往往比猴子和狐猴大。 尽管它们的身体很大，但猩猩是树栖动物。 这些类人猿有长而灵活的手臂和四个用来攀爬的拇指。 所有灵长类动物的眼睛都是直视前方的。 这给了它们双目或三维视觉，帮助它们判断距离。 这使得从一个分支跳到另一个分支更容易!

Squirrels Squirrels are another group that takes to the trees. These small mammals eat only nuts and seeds. Most squirrels are small and light. Their long tails help them balance, even on the thinnest twigs. Strong legs let them leap from tree. to tree Tough claws grab tree bark and hold on. Squirrels can turn their ankles all the way around in order to hang on with their back feet while climbing down headfirst. Do You Know? Flying squirrels have flaps of skin between their legs called patagia. They use these skin flaps to glide from tree to tree.

松鼠是另一种喜欢在树上活动的动物。 这些小型哺乳动物只吃坚果和种子。 大多数松鼠又小又轻。 它们的长尾巴可以帮助它们保持平衡，即使是在最细的树枝上。 强壮的腿让他们从树上跳下来。 坚韧的爪子抓住树皮不放。 松鼠可以转动脚踝，以便在头朝下的时候用后脚抓住。 你知道吗?鼯鼠的两腿之间有一层皮瓣，叫做皮瓣。 它们用这些皮瓣从一棵树滑到另一棵树。