12 Emperors of the Ice-Low

EMPERORS OF THE ICE FOCUS Question How do emperor penguins survive in a cold environment?

帝企鹅如何在寒冷的环境中生存?

A Cold Climate Emperor penguins spend their entire lives in the cold. They live in Antarctica. It is the coldest place on Earth. During the coldest months, emperor penguins may experience temperatures as low as -40°C (-40°F). The wind can blow at 144 kilometers per hour (89 mph), making it even harder to stay warm. Luckily, these penguins have two types of adaptations to help them survive in these frigid conditions. Their bodies are well suited to the cold on land as well as in the icy water, where they spend much of their lives. These birds also behave in ways that keep them as warm as possible.

帝企鹅一生都在寒冷中度过。 他们生活在南极洲。它是地球上最冷的地方。 在最冷的月份，帝企鹅的温度可能低至-40°C(-40°F)。 风速可达144公里每小时(89英里每小时)，这使得保暖更加困难。 幸运的是，这些企鹅有两种适应能力来帮助它们在寒冷的环境中生存。 它们的身体非常适应陆地和冰冷的水中的寒冷，它们在水中度过了生命的大部分时间。 这些鸟的行为方式也尽可能地保持温暖。

Size and Shape Warm-blooded animals stay warm by keeping their body heat inside. Animals lose heat through the outside, or surface, of their body. Larger animals have a larger surface area. So you might think they lose heat faster. But they also have a larger volume—the amount of space their body takes up. Their surface area is not that big compared to their large volume. This feature helps them keep heat inside their body. Emperor penguins are the largest penguin species As a result they have a low surface-area-to- volume ratio (RAY-she-oh) compared to smaller penguins. This physical adaptation helps emperor penguins survive in very cold conditions.

温血动物通过将体温保持在体内来保暖。 动物通过身体的外部或表面散热。 更大的动物有更大的表面积。 所以你可能会认为它们散热更快。 但它们也有更大的体积——它们身体所占的空间。 与体积相比，它们的表面积并没有那么大。 这一特征有助于它们在体内保持热量。 帝企鹅是最大的企鹅物种，因此与小企鹅相比，它们的表面积与体积比(RAY-she-oh)较低。 这种身体上的适应帮助帝企鹅在非常寒冷的环境中生存。

Look at the egret on this page. It is about the same height as an emperor penguin. But this bird does not have a large volume. It has a large surface area compared to the small volume of its body. It loses heat easily, so it could not survive in Antarctica. Size isn't the only way emperor penguins combat the cold. Their oval body shape helps, too. They don't have a long neck, long legs, or big ears and feet. These parts would add to their surface area. In cold weather, they even hold their flippers close to their body to avoid losing heat. SURFACE AREA AND VOLUME OF CUBES Length of each side (inches) 2 4 6 8 Surface area (square inches) 24 96 216 384 Volume (cubic inches) 8 64 216 512 Ratio of surface area to volume 3.0 1.5 1.0 0.75

看这一页上的白鹭。 它和帝企鹅差不多高。 但是这种鸟的体积不大。 与体积小的身体相比，它有很大的表面积。 它很容易散失热量，所以无法在南极洲生存。 体型并不是帝企鹅抵御寒冷的唯一方式。 它们椭圆形的体型也有帮助。 他们没有长脖子，长腿，大耳朵和脚。 这些部件会增加它们的表面积。 在寒冷的天气里，它们甚至会将鳍状肢紧贴身体，以避免热量流失。 立方体的表面积和体积每边的长度(英寸)24 6 8表面积(平方英寸)24 96 216 384体积(立方英寸)8 64 216 512表面积与体积的比值3.0 1.5 1.0 0.75

Recycled Body Heat Penguins do lose some heat through their flippers and feet. Because these body parts stick out from the rest of their body, the blood in the flippers and feet gets cold very quickly. Emperor penguins have a special system that warms up the cold blood before it enters the rest of the body (see diagram). For example, a penguin's heart pumps warm blood through vessels to the base of the feet (step 1). There other vessels carry cold blood from the feet. The vessels with warm blood are close by. They transfer heat to the vessels carrying cold blood (step 2). As a result, the cold blood from the feet warms up before it flows back into the body (step 3). This heat exchange keeps the penguin warmer.

企鹅确实会通过它们的鳍状肢和脚散发一些热量。 因为这些身体部位从身体的其他部分突出来，鳍状肢和脚部的血液很快就会变冷。 帝企鹅有一个特殊的系统，可以在冰冷的血液进入身体其他部位之前将其加热(见图表)。 例如，企鹅的心脏通过血管将温暖的血液泵到脚底(步骤1)。 还有一些血管从脚部携带冰冷的血液。 有温暖血液的血管就在附近。 它们将热量传递给携带低温血液的血管(步骤2)。 因此，脚上冰冷的血液在流回身体之前就会变暖(步骤3)。 这种热交换使企鹅更温暖。

Outer Layers Emperor penguins also have other physical adaptations that help them stay warm. They have four layers of feathers that overlap tightly, like the scales of a fish. These layers trap heat, even when the fierce winter wind is blowing. But the feathers don't work very well when they get wet. To stay warm while they swim, these penguins have a layer of fat beneath their feathery skin. It's as if they have a waterproof blanket wrapped around them at all times. They can chase fish or avoid predators without worrying about getting too cold. Safety! When it's cold outside. put on several layers. Wear a sweater underneath your coat. That layer will trap extra body heat and keep you warm—just like a penguin!

帝企鹅也有其他的身体适应能力来帮助它们保暖。 它们有四层紧密重叠的羽毛，就像鱼鳞一样。 即使冬天寒风凛冽，这些层也能留住热量。 但当羽毛被淋湿时就不太好用了。 为了在游泳时保持温暖，这些企鹅的羽毛皮肤下有一层脂肪。 就好像有一条防水毯一直裹着他们。 它们可以追逐鱼或躲避捕食者，而不用担心太冷。 安全!当外面很冷的时候。 多穿几层。外套里面穿一件毛衣。 这一层可以留住身体额外的热量，让你保持温暖——就像企鹅一样!