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Alice Evans -

As was commonly the case in the scientific communities of the 19th century, Alice Evans's revolutionary work studying pasteurization was largely ignored for no reason other than her gender.

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Alice Evans -

Through decades of study and research, Evans proved that consuming unpasteurized dairy could lead individuals to contract a dangerous bacterial infection called brucellosis. Evans recommended that all dairy should be put through a pasteurization process, but was laughed at by the dairy industry and the scientific community alike, until finally, after 10 years of convincing, pasteurization became common practice.

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Aristarchus -

Ancient Greek astronomer Aristarchus was born in 310 BCE on the island of Samos, and developed one of the most revolutionary theories in human history thousands of years before it was proven.

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Aristarchus -

Aristarchus is credited with developing the first heliocentric theory of the stars that put the Sun, not the Earth, at the center of our solar system. Although he was mocked in his own time, Aristarchus' beliefs were finally absolved in 1610 when the heliocentric theory was proven correct by Renaissance astronomer Galileo.

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The Wright Brothers -

Rightfully so or not, Wilbur and Orville Wright have gone down in history as the inventors of the airplane, a contraption that would go on to change the face of international relations, warfare, commerce, and tourism.

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The Wright Brothers -

But despite being such an obviously revolutionary development, the Wright Brothers' flying machine wasn't an instant hit. In fact, after years of trying to sell their invention to the American government, the Wright Brothers were eventually forced to look to France for support.

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Barbara McClintock -

Today, Barbara McClintock remains the only woman to be awarded an unshared Nobel Prize in the category of Physiology or Medicine. In the middle of the 20th century, however, McClintock was a laughing stock of the scientific community.

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Barbara McClintock -

In reality, McClintock and her research into the nature of DNA were simply too advanced for her contemporaries to follow, and she came under intense scrutiny. It wasn't until decades later that the rest of the scientific community caught up to McClintock and realized she was right about the presence and nature of certain genes called transposons.

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John Snow -

English physician John Snow discovered the cause of London's water-borne cholera outbreak of 1854, with indisputable and empirical evidence to back up his theory.

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John Snow -

Snow studied which water sources cholera patients were drinking from and discovered they invariably drank from the same source. Unfortunately, for both Snow and for London, his arguments were rejected in favor of the ever-prevailing miasma theory, until evidence of contamination in the studied water sources was eventually found.

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Joseph Lister -

It's hard to believe that just a few hundred years ago, before Louis Pasteur developed germ theory in 1870, surgeries were being conducted without doctors first sterilizing the area or even washing their hands.

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Joseph Lister -

And, yet, that is exactly how surgeries were conducted, chalking up all infections and illnesses to "bad air." English physician Joseph Lister proved this "bad air," or "miasma" theory, wrong in the mid-19th century, and developed the world's first antiseptic spray. Unfortunately, it took decades for the medical community to accept that their uncleanliness could possibly be the source of so many infections.

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Ignaz Semmelweis -

Something even as simple as handwashing didn't exist until Hungarian physician Ignaz Semmelweis first made it mandatory for his students to sterilize their hands in a special fluid after returning from autopsies. Once this new rule was implemented, the rate of infection in the rest of the hospital plummeted.

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Ignaz Semmelweis -

While Hungary graciously adopted the new handwashing procedure, Semmelweis had trouble selling the idea to the rest of Europe and was eventually driven mad partially by his frustration towards the world for not adopting his sterilization techniques. Ironically, Semmelweis eventually died from an infected wound on his hand that wasn't treated properly by asylum doctors.

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Robert Goddard -

American physicist Robert Goddard, inventor of the liquid-fuel rocket and the man after whom NASA's Goddard Space Center is named, was met with widespread ridicule when he first proposed the possibility of rocket-powered space exploration.

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Robert Goddard -

Long before the launching of Sputnik in 1957 put space exploration at the forefront of the public imagination, Goddard released a paper in 1919 titled 'A Method for Reaching Extreme Altitudes' that laid out what are now considered the fundamentals of rocket science. Although Goddard is today considered the father of the Space Age and rocket science, his life's work went largely ignored and disrespected throughout his own lifetime.

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Marcello Malpighi -

Today, Italian 17th-century physician Marcello Malpighi is known as the father of microscopic anatomy. He laid the groundwork for advances in physiology and the understanding of the brain.

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Marcello Malpighi -

Partially due to his unknown heritage and partially due to his revolutionary ideas about the human body, Malpighi nor his ideas were ever welcome in Bologna, where he studied, taught, and practiced for most of his life. Near the end of his days, Malpighi was victim to physical assault and home invasion, until eventually his house was burnt down and he was forced to flee to Rome under the protection of the Pope.

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General William Mitchell -

Even after the entire world had come around to the importance and potential of aircraft, they weren't fully utilized for decades. US Army General William Mitchell, a World War I veteran, ardently campaigned for a dedicated flying division of the military, but Mitchell wouldn't live long enough to see his ideas accepted.

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General William Mitchell -

General Mitchell was ignored and dismissed by his superiors every time he moved for an expansion of the US Army's aerial units. Eventually, Mitchell was court-marshaled after speaking out against the military's refusal to evolve. Some years after Mitchell's death, a comprehensive Air Force division of the Army would prove decisive in World War II.

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Giordano Bruno -

While his influence on and participation in the occult and dark arts may overshadow his more scientifically sound beliefs, 16th-century philosopher and theorist Giordano Bruno had ideas about the nature of the universe that were centuries ahead of his time, and may have been the cause of his death.

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Giordano Bruno -

A proto-cosmologist, Bruno was quick to accept a heliocentric model of the solar system. Bruno went even further and claimed that the universe as a whole had no center and was in fact an infinite plane. This, and many other beliefs consider heretical in the 1500s, led to the Catholic Church ordering Bruno's execution. Today, nearly all astronomers share Bruno's belief of an infinite universe.

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William Harvey -

William Harvey, a 16th-century pioneer of anatomy and physiology, was credited as the first person to accurately describe the body's circulatory system and suggest that blood runs through the heart, not the liver, as was believed for more than one thousand years.

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William Harvey -

Beliefs held for that long are often difficult to let go of, and Harvey's discoveries were met with distrust and animosity. The negative response to his life's work led Harvey to become a recluse for the rest of his life, although he is now considered a hero of anatomy.

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Henry Freeman -

Born in 1835, English fisherman and lifeboatman Henry Freeman was one of the first proponents of the use of cork life vests in the maritime industry. Unfortunately, most of his efforts to make their use mandatory fell on deaf ears.

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Henry Freeman -

Until, that is, Freeman and his crew of lifeboatmen were sent out in a particularly nasty storm that reportedly destroyed more than 200 ships off England's east coast. Every lifeboatman sent out in the storm perished, except the one with the life vest: Henry Freeman. After that fateful storm, life vests surged in popularity.

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Alexander Fleming -

Alexander Fleming, the Scottish biologist credited with the discovery of penicillin, a discovery that has often been called the "single greatest victory ever achieved over disease," wasn't immediately recognized as the hero of antibiotics that he's considered to be today.

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Alexander Fleming -

For more than 10 years after his discovery, Fleming tried to explain its importance and its potential in the fight against infections. He published his findings in scholarly journals, and made his case in front of numerous scientific panels, but all to no avail. It wasn't until fellow scientists Ernest Chain and Howard Florey purified penicillin and stabilized the antibiotic that its usefulness was recognized.

Sources: (Ranker) (Bored Panda)

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