From an incandescent mass that underwent sudden changes, the Earth has evolved, without stopping at any time, until it became a habitable place for living beings. This planet is the only one known so far with special characteristics that have made life possible. Plants and animals, including human beings, share this home and coexist in a certain harmony thanks to its characteristics. However, do we know what those conditions on the blue planet are that make life possible?
The miracle of life on planet Earth
On a small insignificant planet in the vastness of space, about 4,000 million years ago, particular conditions occurred that made life possible . From simple organic compounds, such as algae or bacteria; to multicellular organisms, such as animals and plants that appeared only 570 million years ago. The Earth has given life to all living organisms around us thanks to its conditions.
To this day, circumstances have remained relatively stable for most living beings, which has allowed today to estimate that there are approximately 8.7 million species of animals and plants, of which only 1.9 million have been discovered. In addition, it is also known that about 99% of all species that inhabited the Earth at some point in history are now extinct.
Next, we are going to detail one by one the conditions that made life on our planet possible :
- Water in a liquid state .
- The distance between the Earth and the Sun (light and temperature).
- The dimensions of the Earth.
- The existence of atmosphere.
- Special chemical elements.
- Earth’s magnetic field.
Water is essential to develop and maintain life. All the chemical reactions of the metabolism of living beings are carried out in it, and it is the basis of all living organisms that are known. This element is necessary to hydrate, clean, regulate the climate, provide energy and even support life. An essential compound for any type of life to exist.
Perhaps, one of the data that best demonstrates this marked importance for the existence of life is the percentage of water that there is on Earth. Whether in solid, liquid or vapor form, 70% of the planet is made up of water, hence it is commonly called the blue planet , and curiously it is the same percentage of water that is in the human body.
The distance between the Earth and the Sun
The precise distance between the Earth and the Sun, 150 million kilometers, makes the conditions of temperature and light suitable for life .
On the one hand, the passage of sunlight is vital for living beings , such as plants, which need it to carry out photosynthesis, a process by which these beings convert C02 into 02. Without the existence of sunlight , the plants would not exist, and without them, the animals neither.
On the other hand, the average temperature of the Earth oscillates 15ºC, with colder areas and warmer ones depending on the proximity of the star to the different geographical points of the Earth. This also gives rise to the existence of seasons and climatic changes, which in turn allow the presence of many ecosystems that give life to many species.
Temperature, in turn, facilitates the existence of liquid water, an inescapable element for life. Without solar energy, water would not change state and would probably remain in a solid state, so living beings could not survive.
Therefore, the Sun as the main energy source of the entire planet, provides us with light and heat and is essential for the well-being of living organisms that inhabit the Earth, circulates through them and gives them life.
Other characteristics of planet Earth that make life possible are the dimensions or size of the planet and that there is an atmosphere.
The size of the Earth is large enough to attract its atmosphere. In fact, if its size were smaller, its mass would not cause enough gravitational force to retain it; and otherwise, if its mass were greater, and consequently its gravity as well, the atmosphere would become dense and thick, preventing the entry of sunlight.
In addition, the atmosphere could be defined as a protective layer that provides us with elements necessary for life, such as oxygen, and that at the same time protects us from the harmful. Thus, this layer allows the energy of sunlight to penetrate our planet to give rise to life while protecting us from harmful radiation, such as ultraviolet, gamma radiation or X-rays. However, despite the importance of the atmosphere, human beings are unconsciously damaging it, putting our very existence at risk.
Components of the Earth: special chemical elements
A series of chemical elements present on the earth’s surface, that is, the components of the Earth that are a direct result of the rest of the conditions that favor life on Earth , allow the existence of the biomolecules that make up living organisms.
The combination of the chemical elements nitrogen, carbon, oxygen and hydrogen, along with others in smaller quantities also coming from the Earth, make life possible.
The blue planet has an internal structure that extends from the interior of the Earth, the inner core, to its limit where it collides with the solar wind. This structure forges an essential magnetic field or barrier to protect living organisms from solar radiation on the surface, so its main function is focused on maintaining the balance of the planet against the rays of the Sun that hit the Earth.
If this field did not exist, life could not develop because:
- It protects us from harmful radiation from the Sun by acting as a filter or barrier.
- Many birds make guided migrations along it.
- Certain animals are located thanks to it.
- It is essential for the growth of plants.
- In general, it is essential for the health of all organisms.