The earth was formed about 4.6 billion years ago, but at the time contained no water. For the first several hundred million years, it had only a rocky surface, with the hydrogen and oxygen necessary to make water still trapped inside the rocks. As the rocks melted due to the intense heat within the earth’s crust, hydrogen and oxygen atoms were freed, which then combined to form water.
RehydrationWater — the source of life
The water in your body contains electrolytes (ions), and resembles seawater. Learn more about the flow of water from its origins through to becoming an essential part of your body.
The origins of water
1The formation of the earth and water
2The birth of the oceans
In the heat, water rose up as vapor and formed dense clouds surrounding the planet. As the rains eroded the rocks, chemical elements such as carbon, nitrogen, and silicon seeped out, and released sodium, magnesium, potassium, iron, copper, and calcium from the earth’s crust. The water pooled together with these substances, forming an ocean rich in organic matter*.
- 2Organic matter is composed of organic compounds, which primarily consist of carbon and are the basis for the formation of organisms.
Clouds form as the sun’s heat causes the water on the earth’s surface to evaporate. When the clouds cool, water returns to the land or ocean as rain or snow. Most water runs back into the ocean via rivers. This is referred to as the water cycle, and it is repeated as many as 40 times a year.
3The miracle of the planet
Many substances collected in the ocean over a long period of time; these elements were essential for the formation of life. As these raw materials reacted with the complex energy emitted from the tidal ebbs and flows, thermal energy emanating from the Earth’s crust, and electrical energy discharged in the atmosphere, life formed.
The oldest life forms on earth were single-cellular organisms living in water. Over a long period of time, they evolved into multi-cellular organisms giving rise to vertebrates, some of which emerged from the sea and began to breathe air on the land. Through a very long and gradual process of evolution, human beings appeared on the planet.
However, just because some organisms have come to live on land does not mean they do not have any connection with the sea. The human body contains a lot of water in its body fluids. These include blood, spinal fluid and also amniotic fluid, which nurtures new life in the womb. All these fluids contain electrolytes (ions), in proportions similar to those found in the oceans.
Read more about the close connection between water and the human body
Body fluid contains electrolytes, chemicals which, when they dissolve in water, produce charged ions. These ions enable the flow of electrical signals through the body.
Our bodies contain a lot of water — 60% of an adult’s weight, and 80% of a newborn’s weight, is body fluid.
When the body is hot, blood vessels in the skin dilate to increase blood flow and allow perspiration in order to regulate the temperature.