Astronomy

Biodiversity and extinctions

Biodiversity and extinctions

After 4,000 million years of evolution, the most diverse life forms populate the Earth. A large number of animals, plants and other living things form the biodiversity of our planet.

They live from the deep sea to the highest mountain ranges, tropical forests and arid deserts, even polar ice ... The existence of such different habitats is precisely the cause of the diversity of life forms on Earth is so wide and varied .

Since the first unicellular organisms appeared in the sea, billions of species have populated the Earth. After a more or less long survival period, most evolve into new species or end up becoming extinct. The current species are only 1% of all those that have passed through the Earth.

It is estimated that today there are about 100 million species, including animals and vegetables. Although the cataloged do not reach two million. There are many species still unknown. The majority are insects, plants and other small organisms. They are hard to see and sometimes they live in places too inaccessible to humans. Ocean bottoms are still unexplored. Many species become extinct even before they are discovered.

Biodiversity provides the environment with a balance that is necessary for the survival of all living beings. It intervenes in all the natural processes that sustain life: renews the air, maintains the richness of the soil, participates in the cycles of water and carbon, balances the climate and temperature, etc. It acts as a perfect mencanism. The species interact with each other.

The loss of a single species affects the balance of the entire ecosystem. Biodiversity produces the food and resources necessary for all creatures that are part of it. It distributes it differently in different areas of the planet, and adapts to the characteristics of each habitat, in the same way that species evolve to adapt better to the environment in which they live.

The chemical compounds necessary to manufacture the drugs are also obtained from biodiversity. Nature does not waste its resources, and gives each species what it needs. When a species disappears because of man, it may be destroying something it will need.

Today, many species worldwide are in decline or in clear danger of extinction. Experts believe that the sixth great extinction has begun. The great extinctions are something natural in the history of the Earth. It is believed that past extinctions were due to climatic changes. Or the impact of a meteorite, in the case of the great extinction of the Cretaceous, which ended the dinosaurs. But we do not know the cause with certainty. It seems that, this time, the impact of man on the environment is causing or, at least, accelerating extinction.

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