Serendipity: The Role of Chance in Making Scientific Discoveries
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.
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.
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
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 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.
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.
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 chemicals, which was a very risky pursuit.
Fahlberg discovered that a chemical referred to as benzoic sulfimide was responsible for the sweet taste. This chemical eventually became known as saccharin. Fahlberg had made this chemical 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
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.
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.
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.
- The discovery of penicillin from the ACS (American Chemical Society)
- Discovery of penicillin and lysozyme from the National Library of Scotland
- The discovery of cisplatin from the National Cancer Institute
- The origin of non-carbohydrate sweeteners from Elmhust College
- The accidental invention of the microwave oven from Popular Mechanics
© 2012 Linda Crampton