The human body is a complex machine. From the day we are born, our bodies grow and change in response to our environment, diet, and habits. The body has many different organ systems and parts that work together to allow us to breathe, move, see, talk, and digest food all at the same time. Most of the time we are unaware of what is happening in our bodies； usually it is only when we get sick or feel pain that we notice. 

       Many people do not take care of their complex machines. Bad habits like smoking, drinking too much alcohol, and eating junk food damage our bodies. Stress can also cause health problems. People who worry a lot or have busy jobs often don’t get enough sleep or don’t eat properly. We can also damage our bodies when we play sports or get into accidents. Studies done by the Australian government show that most people get hurt because of an accidental slip or fall or because of injuries from car accidents. It’s true that a lot of people go to the hospital because of serious illnesses, but far more people end up there because they simply weren’t being careful.

       Like machines, different body parts sometimes wear down from old age. People over the age of 65 are more likely to fall and hurt themselves, and these injuries—from bad cuts to broken bone—usually require serious medical attention. There are many treatments available to help older people recover from illness and injury. It is now common for older people with damaged joints, for example, to have surgery to replace the old joint with a new one made of plastic or metal. Instead of suffering aches and pains through their retirement days, older people are able to lead happier and more comfortable lives. 

       The best way to take care of your amazing machine is to eat the right foods, do regular exercise, and get enough sleep. Oh, and don’t forget to smile!

       Earthquakes are the shaking and moving of the ground when energy is released in waves. These waves are called seismic waves. These waves are similar to ocean waves, which move through water. However, seismic waves move through the ground. Most earthquakes are caused by the movement of large sections of the Earth’s crust, called plates. The place where two plates meet is called a fault. Faults look like large cracks in the ground. If the two plates move in different directions, they build up energy at the fault line. When enough energy builds up, the stress on the fault becomes too great and it ruptures. This releases the energy and the ground starts to shake.

       Earthquakes can also be caused by other natural events, such as landslides and volcanoes. The first movement of an earthquake, called the main shock, is often followed by smaller ground trembles, called aftershocks. These aftershocks signal that the plates are settling into their new positions. After the main shock, aftershocks can continue for days. According to some estimates, 500,000 earthquakes occur each year around the world. Most are very mild and are only recorded on scientific instruments. Only about 100,000 can be felt by humans. Among these, only about 19 cause major damage in a year.       Major earthquakes in populated areas can cause huge destruction. Buildings collapse, roads and bridges buckle and crack, and electrical and gas lines break and cause fires. If an earthquake happens in the ocean, it makes a series of huge ocean waves called a tsunami. A tsunami travels until it finally reaches land, where it causes large flooding. Scientists are searching for ways to predict earthquakes. They study the historical patterns of earthquakes and monitor the movement of the plates with seismic equipment. While they cannot predict an exact date of a future earthquake, they have a better understanding of when earthquakes are more likely to happen.

      Finding a new lemur species is rare because many of the tiny creatures have become extinct. The recent find means that there are now 49 known species of lemurs in the wild.