An ancient Greek, Xenophanes, was the first person to see a fossil of a fish on a mountain range. He later wrote that there had once been a sea in this place. As long as he was alive, people of that time did not accept his advice. About 2500 years after his death, in the 15th century, an Italian scientist, engineer, and painter, Leonardo da Vinci, found some fossils in the salty sea water. Later, many fossils were also found in a mountain range in northern Italy, which confirmed that there had once been a sea in this place.
It was about the 18th century when an English engineer, William Smith, made a surprising discovery when he was digging for canals in different places. He noticed that different types of fossils were found in different layers of the earth. As the layers of the earth got deeper, the fossils were of organisms with different patterns compared to the layers above.
Later, when geologists started studying the different layers of the earth's soil in depth, they started finding different types of fossils inside it. This is where this important knowledge was founded. Today we all know that our earth came into existence about 6-4 billion years ago. About which it was thought a few centuries ago, it was about 6 to 7 thousand years old. Today, all of us know this, this may be a myth, but it is not a fact. The truth is what this important branch of scientific knowledge, geology, is proving to us with evidence.
Today, paleontologists divide the entire history of this earth into four different periods and tell us about them in detail when and how all these periods began. The picture below has given a lot of information in this regard. Written by: Sohail Afzal
