Astronomy

Origin and evolution of the human being

Origin and evolution of the human being

About 50,000 years ago, a group of men and women left Africa in search of food. They were some of the survivors of a raw glaciation.

Today, 2,000 generations after that trip and with a world population of 7,000 million, it is hard to think that they are the common ancestors of all of us.

Our DNA reveals that we are all one race. The different characters are only the adaptations that our ancestors developed by populating the different corners of the planet. We are all relatives, not so far away. But how has our history and evolution been? What is the origin of the current human being?

Our species, homo sapiens, was born about 200,000 years ago. If the Earth's history if told in one day, the modern man would appear 1.7 seconds before midnight. We are newcomers. Homo sapiens was the chosen species, which survived and evolved. Other similar species tried unsuccessfully and became extinct, such as the Neanderthal.

He too homo sapiens He almost disappeared several times. His intelligence, creativity and genetic mutations saved him from extinction. The climatic changes caused the evolutionary jump of the human species.

The study of fossil remains and genetic analysis of DNA remind us of the origin of the genus homo and its evolution The oldest human remains are in South Africa. About 65,000 years ago, an ice age was about to end humanity. Only a few hundred survived, sheltered in caves of the South African coast. They fed, above all, on tubers and seafood.

But there came a time when food was scarce. They left Africa and embarked on a journey to Southeast Asia. Surprisingly, the first area they populated was Australia. At that time the sea level was very low and only 250 km of water separated Asia from Australia. It remains a mystery how they managed to cross, but it is a fact that they did. The fossil remains of 50,000 years ago confirm it.

45,000 years ago they populated Central Asia, India and China. The group from India adapted very well and grew rapidly. The Chinese group, on the other hand, was isolated for many generations. He developed genetic mutations to better adapt to his habitat. Thus the Asian features were born. But the weather changed again and severe droughts ravaged Asia. The Central Asian group set off for colder lands in search of pastures. They were the first settlers of Europe, 40,000 years ago.

Humans did not arrive in America until 15,000 years ago. Again, climate change was decisive. During the last glaciation, an Asian group crossed the frozen Bering Strait. When the sea level rose again, it was isolated in the new continent and developed the characteristic indigenous features. Only 500 generations ago that man finished conquering all the habitable zones of the planet.

The changes in the climate dominate the evolution of the human being. Today we face a new climate change of unpredictable consequences. Will we know how to adapt to new challenges as ancestors did? Perhaps we are at the doors of a new stage of human evolution.

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