From fire to metals and fossil fuel, numerous key discoveries have served to advance human civilization over thousands of years. Humans have a long history of uncovering earthen materials, natural phenomena, chemical reactions and processes — then building on those findings to further scientific progress. Here are five discoveries that were revolutionary at the time and continue to impact the world.
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DNA is the molecule that encodes genetic information for all living things. Many people think scientists James Watson and Francis Crick discovered DNA. Nope, not so fast. DNA was actually first discovered in 1869 by Swiss physician Friedrich Miescher. He identified what he referred to as “nuclein” in blood cells. The term nuclein eventually evolved into what we know as DNA, the shorthand for deoxyribonucleic acid. Other scientists built on Miescher’s work over the years. Then came the groundbreaking discovery in the field of genetics by Watson and Crick when they accurately identified DNA’s double-stranded helix structure, connected by hydrogen bonds. For their discovery, Watson and Crick won a Nobel Prize in 1962 and worldwide acclaim. In 2014, Watson auctioned off his Nobel Prize medal for over $4 million. The buyer was a Russian billionaire who returned it to Watson a year later. In 2019, Watson was stripped of his honorary titles because of racist comments.
Earth in Motion
Mathematician and astronomer Nicolaus Copernicus discovered that everything in the universe revolved around the sun, rather than the Earth. Up until his discovery, it was believed that the Earth was the center of the universe, with stars, planets and the sun all revolving around our planet. In 1543, he published his great work, On the Revolutions of the Heavenly Spheres, which explained his theories. Among them was that day and night was created by the Earth spinning on its axis. Copernican heliocentrism replaced the conventionally accepted Ptolemaic theory, which asserted that the Earth was stationary. Copernicus’ work was largely unknown during his lifetime, but later gained support. Galileo agreed with Copernicus’ theory and proved it by using a telescope to confirm that the different phases Venus went through resulted from orbiting around the sun. An interesting side note: The remains of Copernicus were found (and later proved by DNA) under a Polish cathedral in 2005. The discovery of Earth’s role in the solar system changed the perception about our place in the world and the universe, and paved the way for modern astronomy.
It’s a common misconception that Ben Franklin discovered electricity with his famous kite experiment. Actually, what he did in his 1752 experiment was use a key and a kite to demonstrate that lightening is a form of electricity. Another myth is that Franklin was struck by lightning. He wasn’t, but the kite was charged by the storm. Back in 600 B.C., it was the ancient Greek philosopher, Thales of Miletus who first observed static electricity when fur was rubbed against fossilized tree resin, known as amber. The word “electric,” derived from the Greek word for amber, was coined by the British scientist and doctor William Gilbert. Regarded as the “father of electricity,” Gilbert was also the first person to use the terms magnetic pole, electric force and electric attraction. In 1600, his six-volume book set, De Magnete, was published. Among other ideas, it included the hypothesis that Earth itself is a magnet.
Louis Pasteur discovered that living microorganisms caused fermentation, which could make milk and wine turn sour. From there, his experiments revealed that these microbes could be destroyed by heating them — a process we now know as pasteurization. This advance was a game changer, saving people from getting sick from the bacteria in unpasteurized foods, such as eggs, milk and cheeses. Before Pasteur, everyday people and scientists alike believed that disease came from inside the body. Pasteur’s work proved that germ theory was true, and that disease was the result of microorganisms attacking. Because of Pasteur, attitudes changed and became more accepting of germ theory — which led to other advancements, such as antiseptic surgical techniques and the discovery of which specific germs caused tuberculosis, cholera and anthrax.
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No, Isaac Newton didn’t really get hit on the head with an apple, as far as we know. But seeing an apple fall from a tree did spark an idea that would lead the mathematician and physicist to discover gravity at the age of just 23. He pondered about how the force pulls objects straight to the ground, as opposed to following a curved path, like a fired canon ball. Gravity was the answer — a force which pulls objects toward each other. The greater the mass an object has, the greater the force or gravitational pull. When objects are farther apart, the weaker the force. Newton’s work and his understanding of gravity is used to explain everything from the trajectory of a baseball to the Earth’s orbit around the sun. And Newton’s discoveries didn’t stop there. In 1687, Newton published his book, Principa, which expanded on his laws of universal gravitation and his three laws of motion. His work laid the foundation for modern physics. Building on the discovery, advancements in the field of electricity continued. And in 1800, Italian physicist Alessandro Volta created the first voltaic pile, an early form of an electric battery.