wind blows sand toward the camel’s face It blinks its long eyelashes and closes its nostrils to keep sand out The camel has not had water in almost a week but it is still healthy This desert wanderer can drink up to 20 gallons 76 L of water in one session It uses the water slowly and efficiently It has been several days since the camel has eaten but the hump on its back stores fat The camel’s body turns this fat into energy Changing to Survive Camels are one of many species that survive in extreme environments Tardigrades are creatures 6 Tardigrades Tardigrades are tiny animals They are approximately 0 01 to 0 02 inches 0 25 0 5 mm long But these creatures are excellent survivors In 2007 scientists put thousands of tardigrades on a satellite and launched it into low-Earth orbit When the satellite landed many of the tardigrades had survived the trip to space Tardigrades survive by going into a resting state Their bodily processes nearly stop The animal becomes a tun or dry husk It can stay like this for decades and become active when it comes into contact with water
Tardigrades can survive the heat of hot springs the pressure of the deep sea and the vacuum of space that can live in sea ice Bar headed geese migrate over the towering Himalayas of southern Asia Giant squid survive in the depths of the sea How do creatures live in these places Like all living species they have adapted Adaptations are changes in a species over a long time Traits that help the species survive are passed down from generation to generation Adaptations can be structural or behavioral A structural adaptation involves changes in something physical such as the feathers on a bird or the fur on a bear A behavioral adaptation is a change in an activity of a population of animals such as birds migrating to winter survive
Humans have also developed some natural adaptations for living in challenging conditions For example scientists have found physical differences between populations that spend their lives at high altitudes and populations that spend their lives at sea level But most human adaptations are behavioral This type of adaptation includes making technologies that allow humans to do things they otherwise would not be able to do Behavioral adaptations allow humans to survive in some of the most difficult circumstances on Earth and beyond 8 IN THE REAL WORLD The Human Thermostat The thermostat for the human body is located in the brain Nerves in the skin send temperature information to the brain If areas are too cold or hot compared to the brain’s temperature messages are sent back to nerves and glands to adjust Too cold and a message causes muscles to shiver This creates heat Too hot and a message goes to the sweat glands to start perspiration When the sweat evaporates it cools the skin
The following excerpt is from a book about how humans survive in extreme conditions The author describes ways humans adapt to different environments Man is the most adaptable of animals He can live in the tropics in the Arctic in deep caves and on high mountains With the aid of special equipment he can survive for prolonged periods even in the depths of the sea and in outer space In extreme environments behavioral adaptation including wearing appropriate clothing is at least as important as physiological adaptation and in environments unnatural to a terrestrial animal under water and in outer space man can survive only with the aid of devices to maintain an immediate environment compatible with human life Source A W Sloan Man in Extreme Environments Springfield IL Thomas 1979 Print 3 Consider Your Audience Adapt this passage for a different audience such as your teacher or friends Write a blog post conveying this same information for the new audience How does your post differ from the original text and why 9 STRAIGHT TO THE SOURCE
