TOP 10 SCIENTIFIC BREAKTHROUGHS WE LITERALLY COULDN'T LIVE WITHOUT

Top 10 Scientific Breakthroughs We Literally Couldn't Live Without
By Patrick Kiger and Colleen Cancio, How Stuff Works, 18 October 2012.

When you stop to think about it, humans are pretty amazing beings. Not only have we managed to stick around in various forms for millions of years, but we've grown into a population of more than 7 billion, scattered virtually all over the planet. And we've done it despite the fact that, compared with much of the rest of the animal kingdom, we're fairly fragile creatures. We're not particularly strong; we lack a tough hide or fur to protect us from the elements; we don't do very well without a regular supply of food and water; and we're vulnerable to a lot of infectious diseases.

We can thank the human brain for keeping our race alive all these years.

Photo: Hemera/Thinkstock.

So what is it that has enabled us to thrive - to the point where, for the most part, we don't spend every waking moment worrying about whether we'll live to see another day? Our saving grace, perhaps, is our highly developed brain and its ability to experiment with, dream up and collaborate on ingenious solutions to life-threatening challenges. There are a multitude of inventions that modern humans have come to depend on to sustain their existence. But here are a few we would find it extremely difficult to live without.

10. The Wheel

One of the earliest uses of the wheel was on Egyptian chariots.

Photo: iStockphoto/Thinkstock.

We've all heard the expression "no need to reinvent the wheel," meaning that a solution already exists for the problem at hand. This saying has added significance when you consider the many ways in which the wheel improved human life, and how long mankind lived without it. Unlike many other early inventions, the wheel was not inspired by nature and several other items were invented before it.

There is some debate among archaeologists regarding when the wheel was first invented, but the earliest actual evidence of a wheel in human history occurs at about 3500 B.C. in Mesopotamia [source: Smithsonian Magazine]. However, this evidence is associated with the wheel's use in pottery-making, not as a tool for transportation. It took another 300 years or so for the people of Mesopotamia to realize that the wheel could also help them to move things from place to place.

Wheels evolved in a few stages throughout history, beginning with the use of logs as rollers to facilitate transportation and continuing on through the replacement of rollers with wheels that rotate on an axle [source: ThinkQuest]. By 2000 B.C., wheeled chariots appear in the archaeological record throughout ancient Egypt. Only by then the wheels had spokes, making them considerably stronger and lighter.

The wheel was probably the most important mechanical invention of all time. Just about all modern mechanical devices use the wheel in some way - cars, buses, bicycles, factory machines, toys, wristwatches, movie reels and more. Not to mention the wheel's continued use for pottery-making and transporting goods by cart - both of which ancient peoples must have appreciated.

9. Plastic

Photo source

Historians describe periods of time in terms of one element in society that had the greatest impact on peoples' lives, such as the Stone Age and the Bronze Age. According to some, we're currently in the middle of the Plastic Age.

The term "plastic" applies to a wide variety of manmade polymers, or long chains of molecules strung together [source: Polymer Science Learning Centre]. Early versions of plastic were made from polymers that occur in nature like cellulose, giving rise to celluloid [source: American Chemical Society].

Plastic took a big leap forward in the early 20th century with the invention of Bakelite, the first material to be made entirely by man. The inventor, Belgian chemist Leo Hendrik Baekeland, mixed phenol and formaldehyde, together and subjected them to heat and pressure. Seemingly overnight, this material was used in electronics, kitchen appliances, jewellery, toys, and countless other products [source: American Chemical Society].

Today, plastic is incorporated into so much of daily life - everything from toothbrushes to satellites and the computer you're using to read this article - that it's difficult to imagine a world without it. However, plastic does have a dark side. For example, research suggests that 95 percent of Americans have detectable amounts of a chemical called BPA in their blood [source: Health Journal]. The jury is still out regarding whether BPA poses a health risk, but the FDA has taken steps to reduce human exposure to it [source: FDA]. Plastics are also implicated in a number of environment disasters, including giant flotillas of plastic debris in the oceans. Nevertheless, plastic is such a part of life that ways will have to be found to curtail its harmful effects rather than eliminating it.

8. Vaccines

A girl gets a shot of one the newer vaccines - the HPV vaccine to prevent cervical cancer.

Photo: Joe Raedle/Getty Images.

Of all the scientific breakthroughs that have transformed humanity, the development of vaccines is undoubtedly among the most important in terms of human survival. Diphtheria, polio, rubella and whooping cough are just a few of the diseases that can be prevented with vaccines [source: History of Vaccines]. In fact, some diseases have been completely eradicated through the use of vaccines. One example is smallpox, which once killed 35 percent of its victims [source: History of Vaccines].

In 1796, English physician Edward Jenner determined that injecting a boy with pus from cowpox blisters (a mild disease transmitted by cows) prevented him from contracting the much deadlier smallpox. At first Jenner's discovery attracted doubt and ridicule but later he was proved to be right and vaccinations became widespread. Incidentally, Jenner coined the word "vaccine" from the Latin word for cow, vacca [source: BBC].

There is no doubt that humans are living longer and healthier lives thanks to the development of vaccines. Most people alive today would not have been around during the time when polio paralyzed between 13,000 and 20,000 people each year or whooping cough killed 9,000 or more children [source: CDC]. The Centres for Disease Control and Prevention (CDC) recommends that children from birth to 6 receive at least 14 different immunizations in the first few years of life. And most parents oblige - each year babies in the U.S. receive more than 10 million vaccinations [source: History of Vaccines]. Some people believe that vaccines, or perhaps the methods used to administer them, are linked with autism or other serious conditions, though current evidence does not support this [source: CDC]

7. Electricity

English chemist and physicist Michael Faraday at work in his bottle-lined laboratory in the

basement of the Royal Institution in London. Photo source.

Humans have known about the existence of electricity for thousands of years. After all, it's abundant in the natural world. But it wasn't until early scientists such as Benjamin Franklin in the 1700s and Michael Faraday in the 1800s began investigating electricity that we came to truly understand it [source: Mr. Nussbaum]. And we wasted no time figuring out how to harness it in order to power human life.

Trying to imagine what life was like before electricity is pretty difficult. Electricity is used to manufacture our homes and cars and it powers everything from appliances to streetlights. Before the discovery and development of electricity, not only did we do nearly every task and household chore by hand, we pretty much had to do them before nightfall.

Electricity is also responsible for making our modern high-tech world possible. It charges our phones, computers, and virtually every other tool of communication used in modern life. Even people who do not have electricity in their homes may use it in their work lives in factories or offices or in commercial activities.

Electricity is produced from a variety of sources such as solar, wind, geothermal, nuclear and fossil fuel energy, and new twists on its production provide innovative solutions to the world problems. These days, scientists and entrepreneurs are coming up with all sorts of new ways to produce electricity, including biofuels sources. There are even teams working on artificial leaves as photosynthesis-derived electricity source [source: Science Daily]. Considering these innovations, the most important contribution of electricity as a scientific breakthrough may be its potential to fuel future breakthroughs.

6. DNA

DNA is a double helix. Photo source: Nature.

The discovery of DNA - the very building blocks of all life - is arguably the most important discovery of the 20th century. DNA, the acronym for deoxyribonucleic acid, was first discovery in the late 1860s by a Swiss chemist named Friedrich Miescher, though much of our understanding of DNA comes from the work of James Watson and Francis Crick, who explained the double helix structure of a DNA strand in 1953 [source: Nature]. Watson and Crick won the Nobel Prize for their work.

In just a few decades, we've come to rely on DNA for such diverse things as paternity testing and criminal investigations. Food production has also benefited tremendously by the discovery of DNA, as scientists have developed methods for growing more nutrient-rich and disease-resistant crops through the use of DNA-based technologies [source: Life in Discovery].

Perhaps most significantly, the discovery of DNA has lead to the identification of genes responsible for countless diseases as well as gene-based therapies designed to prevent or cure them [source: NIH]. While our environment and how we choose to live our lives play a significant role in the person each of us will become, there is no denying that much of what makes up each individual is dictated by DNA.

5. Fire

The making and control of fire was one of the most important developments in the survival

and spread of humanity. Photo: iStockphoto/Thinkstock.

We don't know the identity of the experimenter or experimenters in the Acheulian culture in Africa who discovered how to start, control and utilize fire about 790,000 years ago. But their mastery of rapid oxidation was one of the most important developments that sustained the survival and spread of humanity, according to Nira Alperson-Afil, a member of an Israeli archaeological team that found the earliest evidence of human ability to make and control fire at will.

The invention equipped early humans with a scary deterrent - flaming torches - to protect them and their vulnerable young from predators. It also provided a source of warmth that helped them to survive temperature downturns. Additionally, the ability to cook animal flesh and vegetation increased food choices for humans and helped them to avoid malnutrition. Perhaps more than any other invention, fire was the breakthrough that enabled humans to multiply and spread across the planet's surface. As Alperson-Afil told Science Daily in 2008: "The powerful tool of fire-making provided ancient humans with confidence, enabling them to leave their early circumscribed surroundings and eventually populate new, unfamiliar environments" [source: Science Daily].

Today, we've progressed beyond gathering around the campfire and gnawing hunks of charred mammoth haunches. But the ability to burn fuel remains a crucial part of our continued existence. Without it, we'd have difficulty cooking, and a hard time living in Massachusetts or Minnesota, let alone Alaska. We'd also have to spend a lot of our time cracking and shaping stones by hand to make tools. After all, it was fire that made it possible for Neanderthals to develop metallurgy 300,000 to 400,000 years ago [source: Sherby and Wadsworth].

4. Agricultural Crops

Advancements in agriculture have kept us well fed. Photo: David De Lossy/

Photodisc/Thinkstock.

If we didn't have farms to produce food for us, we would all have to spend much of our time gathering wild plants and stalking animals to survive, the way primitive hunter-gatherers did 12,000 years ago. Hunting and gathering isn't necessarily a bad way to go. For example, its inherent flexibility enables humans to utilize the available resources in a range of habitats efficiently, and it doesn't deplete the ecosystem the way modern civilization does [source: Washington State University]. But it would require us to continually be on the move and limit ourselves to relatively small groups. Contemporary civilization - from standing militaries to factories to shopping malls - would be impractical. That's why the development of agriculture is so important to our survival.

Agriculture really is not one, but a series, of scientific and technical breakthroughs - such as the development of irrigation technologies, and the invention of crop rotation and fertilizers - that occurred over thousands of years. But it all started when humans figured out how to gather seeds from wild plants, plant and tend them, and harvest them. According to DNA analysis of modern foodstuffs, development of the "founder crops" - wheat, barley, chickpeas, lentils, flax and others - dates back about 9,000 to 10,000 years in southwest Asia [source: Harris].

3. Water Purification

A water purification plant. Photo source: Mayuno/Wikimedia Commons.

As many of us who've travelled in the developing world can testify, drinking water that's contaminated with pathogens can lead to a miserable bout of stomach pain and loose bowels, and a hasty trip to a local medical clinic. But water-related illnesses do more than just ruin vacations. As the World Health Organization reported in 2005, such diseases are the world's leading cause of death, claiming 3.4 million lives annually - more than war, terrorism and weapons of mass destruction combined. Children in impoverished countries, whose immune systems already are weakened by malnutrition and other stresses, are particularly at risk; about 4,000 of them die each day from drinking filthy water [source: VOA].

But it used to be even worse. For centuries, even in developed countries, mysterious periodic outbreaks of water-borne cholera regularly killed many thousands of people [source: Britannica]. During a cholera outbreak in 1854, British scientist John Snow determined that the disease was caused by microorganisms in sewage that contaminated the water supply. He came up with the idea to apply chlorine to the water to kill the microorganisms, and the illness rate plummeted. Since then, additional chemical and filtration technologies have been developed to make our drinking water safe [source: Lenntech].

2. Antibiotics

The use of antibiotics has dramatically reduced the death rate linked to certain diseases.

Photo: ©iStockphoto.com/Thinkstock.

For most of human history, virtually everyone on the planet faced the risk of dying in epidemics of bacterial diseases that sometimes ravaged multiple continents. One such disease, Bubonic plague - the "Black Death" - killed an estimated 200 million people in the 14th century alone [source: BBC].

Then, in the late 1920s, a London physician named Dr. Alexander Fleming, who was trying to develop an antibacterial agent, noticed mould that had contaminated a Petri dish inhibited the growth of a pathogen he was studying. Fleming published a scientific article on his discovery in 1929, and one of his students, Dr. Cecil Paine, eventually became the first clinician to demonstrate the effectiveness of penicillin, a drug derived from the mould, against bacterial disease in human patients [source: Wong]. Since then, the use of penicillin and other antibiotics has led to dramatic reductions in the death rate from certain once-common diseases like syphilis, gangrene, scarlet fever, gonorrhoea, and tuberculosis. In Sweden, for example, the death rate from one type of genital tract infection in infants dropped from one in 1,000 in 1911 to one in 100,000 births in 1970 [source: Hemminki].

1. Food Preservation

Photo sources: left, right.

The cans of beans or corn in your pantry might seem like a humble advance in civilization, but there's a reason civil defense officials advise everyone to keep a supply. The ability to preserve foodstuffs for long periods without refrigeration enables people to survive natural and man-made disasters that disrupt our electrical supply and make it difficult to obtain supplies of fresh food.

Canning was invented in the late 18th century out of military necessity. Napoleon's troops were suffering more casualties from hunger and scurvy, a nutritional deficiency, than they were from combat with the enemy, and the French government offered a prize of 12,000 francs to anyone who could develop a method of preserving soldiers' provisions in the field. A Parisian named Nicholas Appert, who had worked variously as a candy maker, chef and beer brewer, came up with the idea of partially cooking food, sealing it in bottles with cork stoppers and then immersing the bottles in boiling water to expel the air inside. He believed the air caused it to spoil. (It would be another half century before Louis Pasteur would discover that heat actually killed the microorganisms that spoiled food and caused illness.)

French soldiers took Appert's samples of poultry, vegetables, gravy and other items along with them when they were sent on an overseas voyage, and they reported that after four months, it remained edible. In 1810, English inventor Peter Durand received a patent for an improved food container, which had a soldered lid instead of a cork. Two years later, two of Durand's countrymen, Bryan Donkin and John Hall, opened a factory that put food into metal cans instead of bottles [source: Cancentral.com].

Sources:

1. American Chemical Society. "Discovery of penicillin." (Mar 3, 2012)

2. BBC News. "Decoding the Black Death." Oct. 3, 2001. (Nov. 23, 2010)

3. Can Manufacturers Institute. "History of the Can." (Nov. 23, 2010)

4. Census.gov. "World Population Summary." Nov 23, 2010. (Nov. 23, 2010)

5. Electricity Forum. "Sources of electricity." (Mar 3, 2012)

6. Encyclopaedia Britannica. "Cholera." 1922. (Nov. 23, 2010)

7. Google Books. "The Origins and Spread of Agriculture and Pastoralism in Eurasia." Harris, David R. UCL Press. 1996. (Nov. 23, 2010.)

8. Health Journal. "BPA or BPA-free?" (Mar 3, 2012)

9. Lawrence Livermore National Laboratory. "Ancient Blacksmiths, the Iron Age, Damascus Steels, and Modern Metallurgy." Sherby, O.D. and Wadsworth, J. International Conference on Processing and Manufacturing of Advanced Materials. Dec. 4-8, 2000. (Nov. 23, 2010)

10. Lenntech.com. "History of Water Disinfection." Lenntech.com. (Nov. 23, 2010)

11. Mr. Nussbaum. "Benjamin Franklin discovers electricity." (Mar 3, 2012)

12. National Library of Medicine. "What is gene therapy?" (Mar 3, 2012)

13. Nature. "Discovery of DNA Structure and Function: Watson and Crick." Pray, Leslie A. (Mar 3, 2012)

14. NIH. "The Effect of Antibiotics on Mortality From Infectious Diseases in Sweden and Finland." Hemminki, Elina MD and Paakkulainen, Anneli. American Journal of Public Health. December 1976. (Nov. 23, 2010)

15. PBS. "Fleming discovers penicillin." (Mar 3, 2012)

16. Rosalind Franklin University. "The importance of DNA."

17. Royal Society of Chemistry. "The discovery and development of penicillin." (Mar 3, 2012)

18. Science Daily. "Debut of the First Practical Artificial Leaf." (Mar 3, 2012)

19. Smithsonian Institution. "Human Evolution Timeline Interactive." Smithsonian Institution. (Nov. 23, 2010)

20. Smithsonian Magazine. "A Salute to the wheel" (Mar 3, 2012)

21. Teachers' domain. "The discovery of penicillin." PBS. (Mar 3, 2012)

22. ThinkQuest. "Invention of the wheel." (Mar 3, 2012)

23. University of Hawaii at Manoa. "Penicillin." Wong, George J. (Nov. 23, 2010)

24. VOANews.com. "WHO: Water-borne Disease is World's Leading Killer." March 17, 2005. (Nov. 23, 2010)

25. Washington State University. "Hunting and Gathering." (Nov. 23, 2010)

[Post Source: How Stuff Works. Edited. Some images added.]