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Serendipity: The Role of Chance in Scientific Discoveries

Linda Crampton has an honors degree in biology. She has taught high school biology, chemistry, and physics as well as middle school science.

Finding a four-leaf clover is considered to be a lucky accident; so is experiencing serendipity.

Finding a four-leaf clover is considered to be a lucky accident; so is experiencing serendipity.

What Is Serendipity?

Serendipity is a happy and unexpected event that apparently occurs due to chance and often appears when we are searching for something else. It's a delight when it happens in our daily lives and has been responsible for many innovations and important advances in science and technology.

It may seem odd to refer to chance when discussing science. Scientific research supposedly operates in a very methodical, precise, and controlled way, with no room for chance in any area of the investigation. In fact, chance plays an important role in science and technology and has been responsible for some significant discoveries in the past. In science, though, chance doesn't have quite the same meaning as it does in everyday life.

Origin of the Word "Serendipity"

The word “serendipity” was first used by Sir Horace Walpole in 1754. Walpole (1717–1797) was an English writer and a historian. He was impressed by a story that he had read called “The Three Princes of Serendip”. Serendip is an old name for the country known today as Sri Lanka. The story described how three traveling princes repeatedly made discoveries about things that they had not planned to explore or that surprised them. Walpole created the word “serendipity” to refer to accidental discoveries.

Scientists are not passive recipients of the unexpected; rather, they actively create the conditions for discovering the unexpected.

— Kevin Dunbar and Jonathan Fugelsang

The Role of Chance in Science

When discussing serendipity in relation to science, “chance” doesn’t mean that nature is behaving capriciously. Instead, it means that a researcher has made an unexpected discovery due to the specific procedures that they chose to follow in their experiment. Those procedures led to serendipity while another set of procedures may not have done so.

A serendipitous discovery in science is often accidental, as its name implies. Some scientists try to design their experiments in a way that increases the chance of serendipity, though.

Many discoveries in science are interesting and meaningful. A serendipitous discovery goes beyond this, however. It reveals a very surprising, often exciting, and frequently useful aspect of reality. The fact that is discovered is part of nature but is hidden from us until a scientist uses suitable procedures for its revelation.

Experimental conditions can trigger serendipity.

Experimental conditions can trigger serendipity.

Experiencing Serendipity

A deliberate change in a recommended procedure, an oversight, or an error may have a significant effect on the outcome of an experiment. The altered procedure may lead to a failed experiment. It may be exactly what is needed to produce a serendipitous discovery, however.

The steps and conditions in an experiment are not the only factors that control serendipity in science. The others are the ability to see that unexpected results may be significant, an interest in finding an explanation for the results, and the determination to investigate them.

The list of serendipitous discoveries in science is very long. In this article, I’ll describe just a small selection of the ones that have been made so far. All of them seem to have been made due to a procedural error. Each of the errors led to a useful discovery.

Penicillium is a mold that makes penicillin.

Penicillium is a mold that makes penicillin.

The Discovery of Penicillin

Probably the most famous serendipitous event reported in science is the 1928 discovery of penicillin by Alexander Fleming (1881–1955). Fleming's discovery began when he was investigating a group of Petri dishes on his messy workbench.

Petri dishes are round and shallow plastic or glass dishes with lids. They are used to grow cultures of cells or microorganisms. They are named after Julius Richard Petri (1852–1921), a German microbiologist, who is said to have created them. The first word in the name of the dishes is often—but not always—capitalized because it’s derived from the name of a person.

Fleming’s Petri dishes contained colonies of a bacterium called Staphylococcus aureus, which he had deliberately placed in the containers. He found that one of the dishes had become contaminated by a mold (a type of fungus) and that there was a clear area around the mold.

Instead of cleaning or discarding the Petri dish and ignoring the contamination as a mistake, Fleming decided to investigate why the clear area had appeared. He discovered that the mold was making an antibiotic that killed the bacteria around it. Fleming identified the mold as Penicillium notatum and named the antibiotic penicillin. (Today there is a debate about the species of Penicillium that was actually located in Fleming's dish.) Penicillin eventually became an extremely important medicine for fighting infections.

What people call serendipity sometimes is just having your eyes open.

— Jose Manuel Barroso

Lysozyme Discovery and Facts

In 1921 (or 1922), Alexander Fleming serendipitously discovered the antibacterial enzyme lysozyme. This enzyme is present in our mucus, saliva, and tears. Fleming found the enzyme after he sneezed—or dropped nasal mucus—on a petri dish full of bacteria. He noticed that some of the bacteria died where the mucus had contaminated the dish.

Fleming discovered that the mucus contained a protein that was responsible for the destruction of the bacterial cells. He named this protein lysozyme. The name was derived from two words used in biology—lysis and enzyme. "Lysis" means the breaking up of a cell. Enzymes are proteins that speed up chemical reactions. Fleming discovered that lysozyme is located in other places besides human secretions, including mammalian milk and the white of eggs.

Lysozyme destroys some of the bacteria that we encounter everyday, but it's not very helpful for a major infection. This is why Fleming didn't become famous until his later discovery of penicillin. Unlike lysozyme, penicillin can treat major bacterial infections—or it could before the worrying development of antibiotic resistance.

Cisplatin: A Cancer Drug

Cisplatin is a synthetic chemical that is an important chemotherapy drug in cancer treatment. It was first made in 1844 by an Italian chemist named Michele Peyrone (1813–1883) and is sometimes known as Peyrone’s chloride. For a long time, scientists had no idea that the chemical could act as a drug and fight cancer. Then in the 1960s researchers at Michigan State University made an exciting and serendipitous discovery.

Effect of an Electric Current on E. Coli Cells

A team led by Dr. Barnett Rosenberg wanted to discover if an electric current affects the growth of cells. They placed the bacterium Escherichia coli in a nutrient solution and applied a current using supposedly inert platinum electrodes so that the electrodes wouldn’t influence the result of the experiment. To their surprise, the researchers found that while some bacterial cells died, others grew up to 300 times longer than normal.

Being curious people, the team investigated further. They discovered that it wasn’t the current itself that was increasing the length of the bacterial cells, as might have been expected. The cause was actually a chemical produced when the platinum electrodes reacted with the solution containing the bacteria under the influence of the electric current. This chemical was cisplatin.

A Chemotherapy Drug

Dr. Rosenberg continued his research and found that the bacterial cells that survived were lengthening because they were unable to divide. He then had the idea that cisplatin might be useful in treating cancer, which results when cell division is rapid and out of control in the cancerous cells. He tested cisplatin on mice tumors and found that it was a very effective treatment for some types of cancer. In 1978, cisplatin was approved as a chemotherapy drug for humans. Even today, it’s a valuable medication.

Sucralose: A Sweetener

In 1975, scientists at the Tate and Lyle sugar company and scientists at King's College London were working together. They wanted to find a way to use sucrose (sugar) as an intermediate substance in chemical reactions unrelated to sweeteners. Shashikant Phadnis was a graduate student helping with the project. He was asked to "test" some chlorinated sugar being prepared as a possible insecticide, but he misheard the request as "taste". He placed a little bit of the chemical on his tongue and found that it was extremely sweet—far sweeter than sucrose. Luckily, he didn't taste anything toxic.

Leslie Hough was the graduate student's advisor. He reportedly called the modified sugar "serendipitose". After its discovery, Phadnis and Hough worked with the Tate and Lyle scientists with a new goal in mind. They wanted to find a low calorie sweetener from chlorinated sucrose that didn't kill insects and could be eaten by humans. Their final version of the chemical was named sucralose.

In some countries, a ladybird (or ladybug) is a symbol of good luck.

In some countries, a ladybird (or ladybug) is a symbol of good luck.

Saccharin: Another Sweetener

The discovery of saccharin is credited to Constantin Fahlberg (1850–1910). In 1879, Fahlberg was working with coal tar and its derivatives in Ira Remsen's chemistry laboratory at John Hopkins University. One day he was working late and forgot to wash his hands before eating supper (or, according to some reports, didn't wash them thoroughly). He was amazed when he found that his bread tasted extremely sweet.

Fahlberg realized that a chemical which he had been using in the lab had contaminated and sweetened the bread. He returned to the lab to find the source of the sweetness. His tests involved tasting different substances, which was a very risky pursuit. Many laboratory chemicals are dangerous when ingested.

Fahlberg discovered that a chemical called benzoic sulfimide was responsible for the sweet taste. This substance eventually became known as saccharin. Fahlberg had made benzoic sulfimide before but had never tasted it. Saccharin became a very popular sweetener.

Success is three parts hard work and one part serendipity; this serendipity is a direct result of the other three parts of hard work.

— Ken Poirot

The Discovery of Aspartame

In 1965, a chemist named James Schlatter was working for the G.D Searle Company. He was trying to create new drugs to treat stomach ulcers. As part of this study, he needed to make a chemical consisting of four amino acids. He first joined two amino acids together (aspartic acid and phenylalanine), forming aspartyl-phenylalanine-1-methyl ester. Today this chemical is known as aspartame.

Once Schlatter had made this intermediate chemical, he accidentally got some of it on his hand. When he licked one of his fingers before picking up a piece of paper he was surprised to notice a sweet taste on his skin. Eventually he realized the cause of the taste and aspartame's future as a sweetener was secured.

A combined microwave and fan-assisted oven; the microwave was developed due to serendipity

A combined microwave and fan-assisted oven; the microwave was developed due to serendipity

The invention of the Microwave Oven

In 1946, the physicist and inventor Percy LeBaron Spencer (1894–1970) was working for the Raytheon corporation. He was conducting research using magnetrons, which were needed in the radar equipment used in World War Two. A magnetron is a device that contains moving electrons under the influence of a magnetic field. The moving electrons cause microwaves to be produced.

Percy Spencer was involved in testing the output of magnetrons. One very significant day he had a chocolate candy bar in his pocket while working with a magnetron in his lab. (Although most versions of the story say that the candy was made of chocolate, Spencer's grandson says that it was actually a peanut cluster bar.) Spencer discovered that the candy bar melted while he worked. He wondered if emissions from the magnetron were responsible for this change, so he placed some uncooked popcorn kernels next to the magnetron and watched as they popped. His next experiment involved placing an uncooked egg near the magnetron. The egg heated up, cooked, and exploded.

Spencer then created the first microwave oven by sending the microwave energy from a magnetron into a metal box that contained food. The microwaves were reflected by the metal walls of the box, entered the food and were converted to heat, cooking the food much faster than a conventional oven. Further refinements created the microwave ovens that so many of us use today.

Serendipity in the Past and the Future

There are many more examples of serendipity in science. Some researchers estimate that up to fifty percent of scientific discoveries are serendipitous. Others think that the percentage might be even higher. Whatever the true percentage, serendipity can be a wonderful phenomenon.

It can be exciting when a researcher realizes that what at first seemed like an error may actually be an advantage. There may be great practical benefits to the discovery that is made. Some of our most important advances in science have been serendipitous. It's very likely that in the future there will be more important discoveries and inventions due to serendipity. That's an intriguing and exciting thought.


© 2012 Linda Crampton


Linda Crampton (author) from British Columbia, Canada on May 09, 2018:

Thank you for the comment and for sharing the very interesting information, Gene.

Gene Levinson on May 09, 2018:

Hi Linda, thanks for posting this informative article on the role of serendipity in scientific research. Serendipity certainly played an important role in my own career--for example, as a doctoral student interested in Developmental Biology, I noticed that a fruit fly (Drosophila) DNA sequence cross-hybridized with DNA sequences from animals as diverse as snakes and mice. It turned out that this was because all of the similar sequences contained similar simple repetitive DNA sequences. This led me to investigate the origins of simple repetitive sequences which are extremely widespread in nature, and to the discovery of the fundamental mechanism for DNA sequence expansion which we called slipped-strand mispairing--also known as replication slippage.

Linda Crampton (author) from British Columbia, Canada on January 10, 2018:

Hi, Bede. Thanks for the comment and for sharing the information about Harry Brearley. I definitely agree that hard work can increase luck!

Bede from Minnesota on January 10, 2018:

Thanks for this enjoyable article. I had an uncle who was considered to be lucky by many people. He would tell them, “The harder I work, the luckier I become.” It seems that many serendipitous discoveries made by people who tinkered for hours in the laboratory. The “eureka “moment was preceded by much sweat. Such was the case with Harry Brearley, who discovered stainless steel.

Linda Crampton (author) from British Columbia, Canada on June 12, 2014:

Thank you very much for the comment, the vote and the interesting quotation, Anne!

Anne Harrison from Australia on June 12, 2014:

A really interesting hub. As Abélard said, by doubting we are led to inquire, by enquiry we are led to the truth; with an open mind, one notices things in a new light, and asks, why. Voted up

Linda Crampton (author) from British Columbia, Canada on August 30, 2013:

Thank you, Ruby. I appreciate your comment.

Maree Michael Martin from Northwest Washington on an Island on August 30, 2013:

Connecting serendipity and science, wonderful, a great way to look at it. Love your examples.

Linda Crampton (author) from British Columbia, Canada on May 08, 2012:

Congratulations on your discovery, Kris! It must have been a great feeling. I agree, forgetting to wash your hands after working with chemicals is very strange. Thank you for the comment!

Kris Heeter from Indiana on May 08, 2012:

Very interesting hub. A significant number of important scientific discoveries are by "accident". I've had a few myself in the lab and I'll always remember the one that was controversial at first but ended up being significant in it's field after publication. It's a fun feeling to stumble upon something you never thought possible:)

The one that always gets me is the artificial sweetener one you mentioned - it's famous and it kind of creeps me out. No scientist in his right mind should be licking his/her fingers after working with chemicals! Yuck:)

Thanks for a great hub!

Linda Crampton (author) from British Columbia, Canada on May 07, 2012:

Thanks for the comment, Alastar. I’ve read the claims that Crick had chemical help when he was contributing to the discovery of DNA’s structure, but I don’t know how reliable the claims are. It's an interesting idea. The idea of another dimension which can communicate with us is also a very interesting topic! I certainly have an open mind with respect to that thought.

Linda Crampton (author) from British Columbia, Canada on May 07, 2012:

Thank you very much for the comment and the share, phdast7!! I appreciate your visit very much. Yes, serendipity and science do sound like strange partners to many people! Their relationship is an interesting topic.

Alastar Packer from North Carolina on May 07, 2012:

This was a very interesting and informative article on science and serendipity Alicia. Would the fact that Crick actually come on the structure of DNA while on LSD not beer as is so often reported fall under serendipity? Do many of these discoverers by whatever means "tune in" to another dimension or plane where the answers to their discoveries are made?

Theresa Ast from Atlanta, Georgia on May 07, 2012:

Wonderful Hub! I offer a History of Science course on the college level and it is always interesting to watch students grapple with, what to them seem like incompatible truths, the fact that science is rigorous and mathematical, and that chance, unplanned and random choices. actions, elements can actually play such a major role in scientific discoveries and understanding.

I love this sentence: "When serendipity occurs, it means that by chance a researcher has created a suitable combination of conditions to get an unusual, often interesting and sometimes very important result from his or her investigation."

Great Hub and Thank you. SHARING

Linda Crampton (author) from British Columbia, Canada on April 18, 2012:

Thank you for the comment, GoodLady. I'm very much looking forward to getting to know you and your hubs, too!

Penelope Hart from Rome, Italy on April 18, 2012:

Serendipity and science. Who's have made the connection? It's a fascinating read. Thanks.

Look forward to reading more and knowing you better!

Linda Crampton (author) from British Columbia, Canada on April 14, 2012:

Thank you for the comment, Larry. Yes, serendipity is certainly very important in our lives! It's a fascinating topic to think about.

Larry Wall on April 14, 2012:

Excellent Hub and it makes an excellent point--experimentation is vital. If we knew the results of X+Y-Z when all three are variables then we would have no need to experiment. We would just solve the problem and move on to the next. A lot of things in our lives are the result of Serendipity. We do not always realize it, but it happens all the time.

Linda Crampton (author) from British Columbia, Canada on April 05, 2012:

Thanks, billybuc! Actually, the only site I have time to write for consistently at the moment is HubPages. I wish there were more hours in the day!

Bill Holland from Olympia, WA on April 05, 2012:

Fascinating topic and hub! I can see the scientist in your writing. You are a busy person with all those sites you write for and the sheer number of articles you write. I am quite impressed.

Linda Crampton (author) from British Columbia, Canada on April 04, 2012:

Thanks for the comment, kidscrafts. Yes, I agree, it is important to stay open to all possibilities!

kidscrafts from Ottawa, Canada on April 04, 2012:

It's a very interesting article. The conclusion is that you have to stay open to what the universe brings at you; to really stay open to the never know!

Linda Crampton (author) from British Columbia, Canada on April 03, 2012:

Thank you so much, Martie! I appreciate your comment and votes. I try to keep my mind "prepared" too, since I love to make serendipitous discoveries!

Martie Coetser from South Africa on April 03, 2012:

AliciaC – I have found this hub of yours staggeringly interesting. You’ve taught me a new word – Serendipity. I knew the concept, but not its name. I, certainly have a “prepared mind”, and this is also a description not familiar to me. I can but only agree with all the comments in here, Alicia, and in particular with drbj’s and A.A. Zavala's.

Voted up, well-written and very interesting ?

Linda Crampton (author) from British Columbia, Canada on April 03, 2012:

Hi, drbj. Thank you for the comment and the vote! Yes, it is great that so many discoveries and inventions have resulted from serendipity. It's a wonderful phenomenon!

drbj and sherry from south Florida on April 03, 2012:

Isn't it wonderful, Alicia, how many inventions were born as a result of serendipity? Accompanied of course by scientists or researchers who were organized and methodical. Thanks for reminding us so delightfully of these mind-bending discoveries. Voted Up.

Linda Crampton (author) from British Columbia, Canada on April 02, 2012:

Thank you very much for the comment, b. Malin. I agree - "serendipity" is a lovely word with a lovely meaning! It's wonderful when it occurs in any area of life, and it can be very useful in science.

b. Malin on April 02, 2012:

What an Interesting Hub Alicia, Yea, for "Serendipity" in Science. I don't know what I'd do without my "Microwave Oven"! I Love the meaning of the word, Serendipity, a Happy and Unexpected Event that occurs do to chance. As a Writer I can really appreciate that thought. Another Excellent Hub, my friend.

Linda Crampton (author) from British Columbia, Canada on April 02, 2012:

Thank you, Tom. I appreciate all your visits, comments and votes very much. I enjoy reading your hubs too!

Thomas Silvia from Massachusetts on April 02, 2012:

Hi my friend,i always enjoy reading your hubs,they always have interesting information and i always learn something new .

Vote up and more !!!

Linda Crampton (author) from British Columbia, Canada on April 02, 2012:

Thank you for the comment, Augustine! Yes, timing is certainly very important in life. It can make a big difference to our experiences!

Augustine A Zavala from Texas on April 02, 2012:

Timing is everything! In science, writing, and in life. Awesome hub Alicia, thank you for sharing.

Linda Crampton (author) from British Columbia, Canada on April 01, 2012:

Thank you for commenting and for the vote, DAWNEMARS!

DAWNEMARS from The Edge of a Forest in Europe on April 01, 2012:

Interesting hub. Voted up! Thanks for sharing this.