15 of the Longest-Running Scientific Studies in History

Most experiments are designed to be done quickly. Get data, analyze data, publish data, move on. But the universe doesn’t work on nice brief timescales. For some things you need time. Lots of time.

1. THE BROADBALK EXPERIMENT // 173 YEARS

In 1842, John Bennet Lawes patented his method for making superphosphate (a common, synthetic plant nutrient) and opened up what is believed to be the first artificial fertilizer factory in the world. The following year, Lawes and chemist Joseph Henry Gilbert began a series of experiments comparing the effects of organic and inorganic fertilizers, which are now the oldest agricultural studies on Earth. For over 150 years parts of a field of winter wheat have received either manure, artificial fertilizer, or no fertilizer. The results are about what you’d expect: artificial and natural fertilized plots produce around six to seven tons of grain per hectare, while the unfertilized plot produces around one ton of grain per hectare. But there’s more. They can use these studies to test everything from herbicides to soil microbes and even figure out oxygen ratios for better reconstruction of paleoclimates.

2. THE PARK GRASS EXPERIMENT // 160 YEARS

Lawes and Gilbert started several more experiments at around the same time. In one of these experiments with hay, Lawes observed that each plot was so distinct that it looked like he was experimenting with different seed mixes as opposed to different fertilizers. The nitrogen fertilizers being applied benefited the grasses over any other plant species, but if phosphorus and potassium were the main components of the fertilizer, the peas took over the plot. Since then, this field has been one of the most important biodiversity experiments on Earth.

3. THE BROADBALK AND GEESCROFT WILDERNESSES // 134 YEARS

Yet another one of Lawes’ experiments: In 1882 he abandoned part of the Broadbalk experiment to see what would happen. What happened was that within a few years, the wheat plants were completely outcompeted by weeds—and then trees moved in [PDF]. In 1900, half of the area was allowed to continue as normal and the other half has had the trees removed every year in one of the longest studies of how plants recolonize farmland.

4. DR. BEAL’S SEED VIABILITY EXPERIMENT // 137 YEARS

In 1879, William Beal of Michigan State University buried 20 bottles of seeds on campus. The purpose of this experiment was to see how long the seeds would remain viable buried underground. Originally, one bottle was dug up every five years, but that soon changed to once every 10 years, and is now once every 20 years. In the last recovery in 2000, 26 plants were germinated, meaning slightly more than half survived over 100 years in the ground. The next will be dug up in 2020, and (assuming no more extensions) the experiment will end in 2100.

Even if it is extended for a while, there will probably still be viable seeds. In 2008, scientists were able to successfully germinate a circa-2000 year old date palm seed, and four years later, Russian scientists were able grow a plant from a 32,000 year old seed that had been buried by an ancient squirrel.

5. THE PITCH DROP EXPERIMENT // 86 YEARS

If you hit a mass of pitch (the leftovers from distilling crude oil) with a hammer, it shatters like a solid. In 1927, Thomas Parnell of the University of Queensland in Australia decided to demonstrate to his students that it was actually liquid. They just needed to watch it for a while. Some pitch was heated up and poured into a sealed stem glass funnel. Three years later, the stem of the funnel was cut and the pitch began to flow. Very slowly. Eight years later, the first drop fell. Soon the experiment was relegated to a cupboard to collect dust, until 1961 when John Mainstone learned of its existence and restored the test to its rightful glory. Sadly, he never saw a pitch drop. In 1979 it dropped on a weekend, in 1988 he was away getting a drink, in 2000 the webcam failed, and he died before the most recent drop in April 2014.

As it turns out, the Parnell-initiated pitch drop experiment isn’t even the oldest. After it gathered international headlines, reports of other pitch drop experiments became news. Aberystwyth University in Wales found a pitch drop experiment that was started 13 years before the Australian one, and has yet to produce a single drop (and indeed is not expected to for another 1300 years), while the Royal Scottish Museum in Edinburgh found a pitch drop experiment from 1902. All of them prove one thing though: With enough time, a substance that can be shattered with a hammer still might be a liquid.

6. THE CLARENDON DRY PILE // 176-191 YEARS

Around 1840, Oxford physics professor Robert Walker bought a curious little contraption from a pair of London instrument makers that was made up of two dry piles (a type of battery) connected to bells with a metal sphere hanging in between them. When the ball hit one of the bells, it became negatively charged and shot towards the other positively charged bell where the process repeats itself. Because it uses only a minuscule amount of energy, the operation has occurred ten billion times and counting. It’s entirely possible that the ball or bells will wear out before the batteries fully discharge.

Although we don’t know the composition of the battery itself (and likely won’t until it winds down in a few hundred years), it has led to scientific advancements. During WWII, the British Admiralty developed an infrared telescope that needed a battery capable of producing high voltage, low current, and that could last forever. One of the scientists remembered seeing the Clarendon Dry Pile—also referred to as the Oxford Electric Bell—and was able to find out how to make his own dry pile for the telescope.

7. THE BEVERLY (ATMOSPHERIC) CLOCK // 152 YEARS

Sitting in the foyer of the University of Otago in New Zealand is the Beverly Clock. Developed in 1864 by Arthur Beverly, it is a phenomenal example of a self-winding clock. Beverly realized that, while most clocks used a weight falling to get the energy to run the clock mechanism, he could get the same energy with one cubic foot of air expanding and contracting over a six-degree Celsius temperature range. It hasn’t always worked; there have been times it needed cleanings, it stopped when the Physics department moved, and if the temperature is too stable it can stop. But it’s still going over 150 years later.

8. THE AUDUBON CHRISTMAS BIRD COUNT // 116 YEARS

Since 1900, folks from across the continent have spent time counting birds. What began as an activity to keep people from hunting our feathered friends on Christmas Day, has turned into one of the world’s most massive and long-lasting citizen science projects. Although the 2015 results aren’t ready yet, we know that in 2014, 72,653 observers counted 68,753,007 birds of 2106 species.

9. THE HARVARD STUDY OF ADULT DEVELOPMENT // 78 YEARS

One of the longest running development studies, in 1938 Harvard began studying a group of 268 sophomores (including one John F. Kennedy), and soon an additional study added 456 inner-city Bostonians. They’ve been followed ever since, from World War II through the Cold War and into the present day, with surveys every two years and physical examinations every five. Because of the sheer wealth of data, they’ve been able to learn all kinds of interesting and unexpected things. One such example: The quality of vacations one has in their youth often indicates increased happiness later in life.

10. THE TERMAN LIFE CYCLE STUDY // 95 YEARS

In 1921, 1470 California children who scored over 135 on an IQ test began a relationship that would turn into one of the world’s most famous longitudinal studies—the Terman Life Cycle Study of Children with High Ability.  Over the years, in order to show that early promise didn’t lead to later disappointment, participants filled out questionnaires about everything from early development, interests, and health to relationships and personality.  One of the most interesting findings is that, even among these smart folk, character traits like perseverance made the most difference in career success.

11. THE NATIONAL FOOD SURVEY // 76 YEARS

Starting in 1940, the UK’s National Food Survey tracked household food consumption and expenditure, and was the longest lasting program of its kind in the world. In 2000 it was replaced with the Expenditure and Food Survey, and in 2008 the Living Costs and Food Survey. And it’s provided interesting results. For instance, earlier this year it was revealed that tea consumption has fallen from around 23 cups per person per week to only eight cups, and no one in the UK ate pizza in 1974, but now the average Brit eats 75 grams (2.5 ounces) a week.

12. THE FRAMINGHAM HEART STUDY // 68 YEARS

In 1948, the National Heart, Lung, and Blood Institute teamed up with Boston University to get 5209 people from the town of Framingham to do a long-term study of how cardiovascular disease developed. Twenty-three years later they also recruited the adult children of the original experiment and in 2002 a third generation. Over the decades, the Framingham Heart Study researchers claim to have discovered that cigarette smoking increased risk, in addition to identifying potential risk factors for Alzheimer’s, and the dangers of high blood pressure.

13. THE E. COLI LONG TERM EVOLUTION EXPERIMENT // 26 YEARS

While this one might not seem that impressive in terms of length, it has to be the record for number of generations that have come and gone over the course of the study: well over 50,000. Richard Lenski was curious whether flasks of identical bacteria would change in the same way over time, or if the groups would diverge from each other. Eventually, he got bored with the experiment, but his colleagues convinced him to keep going, and it’s a good thing they did. In 2003, Lenski noticed that one of flasks had gone cloudy, and some research led him to discover that the E. coli in one of the flasks had gained the ability to metabolize citrate. Because he had been freezing previous generations of his experiment, he was able to precisely track how this evolution occurred.

14. THE BSE EXPERIMENT // 11 YEARS

Sadly, sometimes things can go terribly wrong during long-term experiments. Between 1990 and 1992, British scientists collected thousands of sheep brains. Then, for over four years, those prepared sheep brains were injected into hundreds of mice to learn if the sheep brains were infected with BSE (mad-cow disease). Preliminary findings suggested that they were, and plans were drawn up to slaughter every sheep in England. Except those sheep brains? They were actually cow brains that had been mislabeled. And thus ended the longest running experiment on sheep and BSE.

15. THE JUNEAU ICEFIELD RESEARCH PROGRAM // 68 YEARS

Attention to glacier retreat and the effects of global warming on the world’s ice fields has rapidly increased over the course of the last few decades, but the Juneau Icefield Research Program has been monitoring the situation up north since 1948. In its nearly 70 years of existence, the project become the longest-running study of its kind, as well as an educational and exploratory experience. The monitoring of the many glaciers of the Juneau Icefield in Alaska and British Columbia has a rapidly approaching end date though—at least in geological terms. A recent study published in the Journal of Glaciology predicts that the field will be gone by 2200.

10 of the Best Indoor and Outdoor Heaters on Amazon

Mr. Heater/Amazon
Mr. Heater/Amazon

With the colder months just around the corner, you might want to start thinking about investing in an indoor or outdoor heater. Indoor heaters not only provide a boost of heat for drafty spaces, but they can also be a money-saver, allowing you to actively control the heat based on the rooms you’re using. Outdoor heaters, meanwhile, can help you take advantage of cold-weather activities like camping or tailgating without having to call it quits because your extremities have gone numb. Check out this list of some of Amazon’s highest-rated indoor and outdoor heaters so you can spend less time shivering this winter and more time enjoying what the season has to offer.

Indoor Heaters

1. Lasko Ceramic Portable Heater; $20

Lasko/Amazon

This 1500-watt heater from Lasko may only be nine inches tall, but it can heat up to 300 square feet of space. With 11 temperature settings and three quiet settings—for high heat, low heat, and fan only—it’s a dynamic powerhouse that’ll keep you toasty all season long.

Buy it: Amazon

2. Alrocket Oscillating Space Heater; $25

Alrocket/Amazon

Alrocket’s oscillating space heater is an excellent addition to any desk or nightstand. Using energy-saving ceramic technology, this heater is made of fire-resistant material, and its special “tip-over” safety feature forces it to turn off if it falls over (making it a reliable choice for homes with kids or pets). It’s extremely quiet, too—at only 45 dB, it’s just a touch louder than a whisper. According to one reviewer, this an ideal option for a “very quiet but powerful” heater.

Buy it: Amazon

3. De’Longhi Oil-Filled Radiator Space Heather; $79

De’Longhi/Amazon

If you prefer a space heater with a more old-fashioned vibe, this radiator heater from De’Longhi gives you 2020 technology with a vintage feel. De’Longhi’s heater automatically turns itself on when the temperatures drops below 44°F, and it will also automatically turn itself off if it starts to overheat. Another smart safety feature? The oil system is permanently sealed, so you won’t have to worry about accidental spills.

Buy it: Amazon

4. Aikoper Ceramic Tower Heater; $70

Aikoper/Amazon

Whether your room needs a little extra warmth or its own heat source, Aikoper’s incredibly precise space heater has got you covered. With a range of 40-95°F, it adjusts by one-degree intervals, giving you the specific level of heat you want. It also has an option for running on an eight-hour timer, ensuring that it will only run when you need it.

Buy it: Amazon

5. Isiler Space Heater; $37

Isiler/Amazon

For a space heater that adds a fun pop of color to any room, check out this yellow unit from Isiler. Made from fire-resistant ceramic, Isiler’s heater can start warming up a space within seconds. It’s positioned on a triangular stand that creates an optimal angle for hot air to start circulating, rendering it so effective that, as one reviewer put it, “This heater needs to say ‘mighty’ in its description.”

Buy it: Amazon

Outdoor Heaters

6. Mr. Heater Portable Buddy; $104

Mr. Heater/Amazon

Make outdoor activities like camping and grilling last longer with Mr. Heater’s indoor/outdoor portable heater. This heater can connect to a propane tank or to a disposable cylinder, allowing you to keep it in one place or take it on the go. With such a versatile range of uses, this heater will—true to its name—become your best buddy when the temperature starts to drop.

Buy it: Amazon

7. Hiland Pyramid Patio Propane Heater; Various

Hiland/Amazon

The cold’s got nothing on this powerful outdoor heater. Hiland’s patio heater has a whopping 40,000 BTU output, which runs for eight to 10 hours on high heat. Simply open the heater’s bottom door to insert a propane tank, power it on, and sit back to let it warm up your backyard. The bright, contained flame from the propane doubles as an outdoor light.

Buy it: Amazon

8. Solo Stove Bonfire Pit; $345

Solo Stove/Amazon

This one is a slight cheat since it’s a bonfire pit and not a traditional outdoor heater, but the Solo Stove has a 4.7-star rating on Amazon for a reason. Everything about this portable fire pit is meticulously crafted to maximize airflow while it's lit, from its double-wall construction to its bottom air vents. These features all work together to help the logs burn more completely while emitting far less smoke than other pits. It’s the best choice for anyone who wants both warmth and ambiance on their patio.

Buy it: Amazon

9. Dr. Infrared Garage Shop Heater; $119

Dr. Infrared/Amazon

You’ll be able to use your garage or basement workshop all season long with this durable heater from Dr. Infrared. It’s unique in that it includes a built-in fan to keep warm air flowing—something that’s especially handy if you need to work without wearing gloves. The fan is overlaid with heat and finger-protectant grills, keeping you safe while it’s powered on.

Buy it: Amazon

10. Mr. Heater 540 Degree Tank Top; $86

Mr. Heater/Amazon

Mr. Heater’s clever propane tank top automatically connects to its fuel source, saving you from having to bring any extra attachments with you on the road. With three heat settings that can get up to 45,000 BTU, the top can rotate 360 degrees to give you the perfect angle of heat you need to stay cozy. According to a reviewer, for a no-fuss outdoor heater, “This baby is super easy to light, comes fully assembled … and man, does it put out the heat.”

Buy it: Amazon

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Your Tattoos Could Be Messing With Your Sweat Glands

Tattoos might inhibit a person's ability to sweat.
Tattoos might inhibit a person's ability to sweat.
vgajic/iStock via Getty Images

For centuries, tattoos have reflected cultural traditions, personal beliefs, self-expression, and one’s preferred motorcycle club affiliation. But those who have used their bodies as a giant canvas for permanent ink with meaning might have a little trouble cooling off. That’s because tattoos might actually be interfering with sweating, according to a new study.

A paper published in the Journal of Applied Physiology recruited 10 subjects with tattoos and had them wear tube-lined suits containing warm water. When fitted against the skin, the warmth induced sweating. Skin covered by a tattoo produced roughly 15 percent less sweat than unmarked skin in the same subject.

While the sample size was small, the study follows other research into the effects of tattooing on sweat glands. In 2017, Alma College’s Maurie Luetkemeier used an electric current to produce sweat and found inked skin produced 50 percent less sweat, though the method to promote the sweat was considerably different than how the body cools itself naturally. Another study used exercise to observe sweating and found no difference in tattooed and non-tattooed skin.

This latest research seems to indicate that thermal-induced sweating can indeed be interrupted by tattoo ink and that a person’s sweat glands suffer an undetermined amount of damage as a result of being tattooed, which involves a needle being inserted into the skin’s dermal layer. While further research will be needed to make more solid conclusions, it’s something to consider the next time you ponder getting that full-back dragon rendering.

[h/t New Atlas]