In England and other parts of Europe, you can still see cottages built with thatched roofs. The roofs are made from water reeds or grasses. Thatched roofs are waterproof, but they burn easily.
In Mongolia, nomadic tribes live in domed tents called gels or yurts. These homes are covered with cloth insulated with wool or fur. The homes are open with a stove in the center for cooking and heating.
The Bagobo tribe in the Philippines lived in tree houses, which kept them safe from snakes, dangerous animals and enemies. Today, the tree houses are mostly used for rest and play.
Many people around the world live in caves even today, but these homes are anything but primitive. In Southern Spain, for example, people have built spacious, comfortable homes in caves.
Vitamin D helps our bodies absorb calcium from foods. At our latitude in Canada, we cannot make vitamin D from the sun for about half the year (October to March). As a result, a daily dietary source of vitamin D is important. There are only a few commonly consumed foods naturally rich in vitamin D. These include cod liver oil, salmon, mackerel and tuna. You can also get smaller amounts of vitamin D from egg yolks, liver and margarine. Milk in Canada is fortified with vitamin D so that 1 cup (250 mL) provides 100 IU.
Fluid needs vary depending on your age and gender. Teens and adults need anywhere between 8 and 13 cups of fluid each day. Water is great, but milk, juice, soup and anything else you drink also count as fluid.
Carbohydrate is stored as glycogen in muscles, where it is used as a source of quick energy. If you deplete your glycogen stores during long steady intense activity like marathon running, you will become fatigued and exhausted. The only way to refill muscle glycogen stores is by eating carbohydrate-rich foods. The best carbohydrate food choices are nutritious high carbohydrate foods from the four food groups such as fruit, potatoes, bread, pasta, rice, cereal, legumes, milk and fruit-flavoured yogurt.