Top 10 revolutionary scientific theories

Most scientific fields have been made over with a revolutionary theory at least once in recent centuries. Such makeovers, or paradigm shifts, reorder old knowledge into a new framework. Revolutionary theories succeed when the new framework makes it possible to solve problems that stymied the previous intellectual regime. Here are my favorite revolutions. I’m hoping for more before I die.

10. Information theory: Claude Shannon, 1948
It’s not exactly the most revolutionary theory, since there really wasn’t a predecessor theory to revolutionize. But Shannon certainly provided the mathematical foundation for a lot of other revolutionary developments involving electronic communication and computer science. Without information theory, bits would still be just for drills.

9. Game theory: John von Neumann and Oskar Morgenstern, 1944 (with important embellishments from John Nash in the 1950s)
Developed for economics, where it has had some successes, game theory didn’t quite completely revolutionize that field. But it has been widely adopted by many other social sciences. And evolutionary game theory is an important branch of the study of evolutionary biology. Game theory even applies to everyday activities like poker, football and negotiating for higher pay for bloggers. There is also even such a thing as quantum game theory, which is bound to revolutionize something someday. John Nash won a Nobel Prize for his contributions to game theory, and his troubled life inspired the excellent book A Beautiful Mind. But don’t expect to learn anything about game theory by watching the movie version.                   

8. Oxygen theory of combustion: Antoine Lavoisier, 1770s
Lavoisier did not discover oxygen, but he figured out that it was the gas that combined with substances as they burned. Lavoisier thereby did away with the prevailing phlogiston theory and paved the way for the development of modern chemistry. It was a much safer revolution for Lavoisier than the political one that soon followed in France, so revolutionary that Lavoisier lost his head over it.

7. Plate tectonics: Alfred Wegener, 1912; J. Tuzo Wilson, 1960s
Wegener realized that the continents drifted around as early as 1912. But it wasn’t until the 1960s that scientists put the pieces together in a comprehensive theory of plate tectonics. Wilson, a Canadian geophysicist, was a key contributor of some of the major pieces, while many other researchers also played prominent roles. (Keep in mind that plate tectonics should not be confused with Plates Tectonic, a good name for a revolutionary science-theme restaurant.)

6. Statistical mechanics: James Clerk Maxwell, Ludwig Boltzmann, J. Willard Gibbs, late 19th century
By explaining heat in terms of the statistical behavior of atoms and molecules, statistical mechanics made sense of thermodynamics and also provided strong evidence for the reality of atoms. Besides that, statistical mechanics established the role of probabilistic math in the physical sciences. Modern extensions of statistical mechanics (sometimes now called statistical physics) have been applied to everything from materials science and magnets to traffic jams and voting behavior. And even game theory.

5. Special relativity: Albert Einstein, 1905
In some ways special relativity was not so revolutionary, because it preserved a lot of classical physics. But come on. It merged space with time, matter with energy, made atomic bombs possible and lets you age slower during spaceflight. How revolutionary do you want to get?

4. General relativity: Einstein, 1915
General relativity was much more revolutionary than special relativity, because it ditched Newton’s law of gravity in favor of curved spacetime. And opened scientists’ eyes to the whole history of the expanding universe. And provided science fiction writers with black holes.

3. Quantum theory: Max Planck, Einstein, Niels Bohr, Werner Heisenberg, Erwin Schrödinger, Max Born, Paul Dirac, 1900–1926
Quantum theory ripped the entire fabric of classical physics to shreds, demolished ordinary notions of the nature of reality, screwed up entire philosophies of cause and effect and revealed peculiarities about nature that nobody, no matter how imaginative, could ever have imagined. Seriously, it’s hard to believe it’s only Number 3.

2. Evolution by natural selection: Charles Darwin, 1859
Darwin showed that the intricate complexity of life and the intricate relationships among life-forms could emerge and survive from natural processes, with no need for a designer or an ark. He opened the human mind to pursuing natural science unimpaired by supernatural prejudices. His theory was so revolutionary that some people still doubt it. They shouldn’t.

1. Heliocentrism: Copernicus, 1543
One of the greatest insights ever, conceived by some ancient Greeks but established only two millennia later: the Earth revolves around the sun (as do other planets). It’s Number 1 because it was the first. Where did you think word revolutionary came from, anyway? (It was only rarely used to mean what it does today before Copernicus put revolutions in the title of his revolutionary book.)

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Superflexible, 3-D printed “bones” trigger new growth

A highly flexible 3-D printed scaffold used to repair broken or damaged bones.

“Hyperelastic bones” don’t impart Stretch Armstrong abilities, but they could give surgeons a quick, inexpensive way to repair bone breaks. Created by Ramille Shah, a materials science engineer at Northwestern University in Chicago, and colleagues, the new superflexible material can be 3-D printed into femurs, skullcaps and other bone shapes

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The durable material is a mix of an elastic polymer plus hydroxyapatite, a calcium mineral found in human bones and teeth. Once implanted, the material’s mineral makeup encourages real bone to start growing within a month to replace the scaffold, the team reported in the Sept. 28 Science Translational Medicine.

So far, the “bones” have been tested only in animals. In rats, spinal implants stimulated tissue and bone growth just as well as natural grafts, with no signs of rejection. In a macaque with skull damage, an implant almost seamlessly integrated with the monkey’s natural skull tissue within a month. Because the material is malleable, surgeons can fix it in place without glue or sutures, Shah says. A future of easily replacing missing, damaged or deformed bones may no longer be such a stretch.

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African elephants walk on their tippy-toes

Elephants don’t wear high heels, but they certainly walk like they do.

Foot problems plague pachyderm conservation efforts. But it’s not clear if being in captivity causes changes in walking gait that drive these foot problems or whether the environment messes with their natural walking style. 

Testing walking in wild elephants is challenging, so evolutionary morphologist Olga Panagiotopoulou of the University of Queensland and her colleagues opted for the closest thing. Researchers trained five African elephants (Loxodonta africana) at a park in South Africa to walk over pressure-sensing platforms to map the distribution of weight on their feet. The team compared their data tosimilar tests of Asian elephants (Elephas maximus) in a zoo in England.

Regardless of species or setting, a trend emerged: Elephants put the most pressure on the outside toes of their front feet and the least pressure on their heels, scientists report October 5 in Royal Society Open Science. Thus, elephants naturally walk on their tiptoes, and harder surfaces of captive environments must cramp their walking style. As a potential monitoring system, the pressure plates used in the study could aid conservationists and elephant podiatrists.

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Russia’s Lake Baikal

Toward the end of September, wildfires raging near Russia’s Lake Baikal lofted thick clouds of smoke that cast a pall over a huge region. Picked up by east-to-west winds, the smoke was blown more than 3,000 miles to the east, all the way out into the Pacific Ocean.

Make sure to check out the animation lower down in this post showing aerosols from the fires drifting east. But first, some background on these fires:

Siberia has experienced a long-term upward trend in average temperatures near the surface, as seen in this time series beginning in 1979 and continuing through the end of 2015. (Source: Climate Reanalyzer, University of Maine)

This year brought a large number of particularly intense wildfires to Siberia. And a “long dry period and unusual warm weather” helped keep the fires blazing several weeks past the normal end of the wildfire season, according to Sergey Verkhovets of Siberian Federal University, quoted in Gizmodo.

The season typically winds down in early September when the first snowflakes start to fly. Satellite imagery shows some wildfire activity extending into early October.

The image at the top of this post shows the smoke from dozens of individual blazes, as seen by NASA’s Terra satellite on Sept. 28, 2016. The red dots mark places where a sensor on Terra detected active burning.

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How gene editing is changing what a lab animal looks like

Anyone who reads news about science (at Science News or otherwise) will recognize that, like the X-Men or any other superhero franchise, there’s a recurring cast of experimental characters. Instead of Magneto, Professor X, Mystique and the Phoenix, scientists have mice, fruit flies, zebrafish and monkeys. Different types of studies use different stand-ins: Flies for genetics; zebrafish for early development; rats and mice and monkeys for cancer, neuroscience and more. Many of these species have been carefully bred so they are genetically identical, giving scientists maximum control as they study changes in genetics or environment. These animal models have added huge volumes to our understanding of human and animal biology, and will continue to add to our knowledge for many years to come.

Now, new techniques such as gene editing mean that scientists can probe and alter the genes of any animal. The methods open the door for new organisms — such as squid and octopuses — to join scientists’ basic toolkits. With these new arrivals come new questions. What is needed for a good animal model, and how are gene-snipping tools changing the game?

In the early days of biology, the main emphasis was on description of organisms. But description did not allow for experimentation. “One of the major reasons for doing experiments is [that] you can control a system and make predictions from it,” says Garland Allen, a science historian at Washington University in St. Louis. To conduct good experiments, scientists needed models — stand-ins that had some characteristic they needed to know about, whether that was, say, genetics, heart function or behavior. Those stand-ins had to be well-controlled, well-characterized animals that could be kept the same in every way. Once experiments were conducted in those models, the findings could be applied to other species.

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Birds’ honks filled Late Cretaceous air

Some ancient birds may have sounded like honking ducks.

For the first time, scientists have discovered the fossilized remains of a voice box from the age of the dinosaurs. The sound-making structure, called a syrinx, belonged toVegavis iaai, a bird that lived 68 million to 66 million years ago, researchers report October 12 in Nature.

“It may be a once-in-a-lifetime discovery,” says evolutionary biologist Patrick O’Connor of Ohio University in Athens, who wrote a commentary in Nature about the fossil. Now, he says, the hunt will be on to find voice boxes in other fossils.

The new work helps fill in the soundscape of the Late Cretaceous Epoch. It could also offer hints about sounds made by all sorts of dinosaurs, says study coauthor Julia Clarke of the University of Texas at Austin.

Unlike in humans, where the larynx lies below the throat, birds’ voice boxes rest inside the chest at the base of the windpipe. Stacked rings of cartilage anchor vibrating membranes that make sound when air whooshes through.

This delicate structure doesn’t typically fossilize. In fact, scientists have previously spotted just a few syrinxes in the fossil record. The oldest known, from a wading bird, was about 50 million years old. Clar

ke’s team examined that syrinx, which hadn’t been studied before, and the one from V. iaai.

J.A. CLARKE ET AL/NATURE 2016

The V. iaai fossil, a partial skeleton discovered on an island off the coast of Antarctica, was removed from a rock about the size of a cantaloupe, Clarke says. Just one small area remained encased in rocky material. Everyone thought that bit was trivial, she says. But “it was within that tiny little section that I saw the syrinx.” Three-dimensional CT scans let her peer within the rock and see the telltale rings of a voice box, a structure roughly

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Ocean archaea more vulnerable to deep-sea viruses than bacteria

Deep-sea viruses aren’t just dealers of disease; they’re crucial players in Earth’s nutrient cycles. In marine sediments, virus assassinations of single-celled life-forms called archaea play a much larger role in carbon and other chemical cycles than previously thought, new research suggests. For instance, those microbial murders release as much as 500 million metric tons of carbon annually worldwide, researchers report online October 12 in Science Advances.

Viruses are a major killer of bacteria and archaea in the deep sea, busting open infected cells like water balloons and spewing the cells’ innards. To find the relative number of massacred microbes, marine ecologist Roberto Danovaro of Polytechnic University of Marche in Ancona, Italy, and colleagues studied the spilled guts of the viruses’ victims.

Tallying the number of archaeal versus bacterial genes released from the carnage in more than 480 sediment samples, the researchers discovered that viruses kill archaea disproportionately more often than bacteria

. Despite making up on average about 12 percent of the microbial population in the top 50 centimeters of sediment, archaea accounted for up to one-third of the total biomass killed by viruses, Danovaro and colleagues report. The researchers do not speculate on why archaea were such frequent targets. Those deaths were not in vain, though: Archaea corpses supply nutrients such as carbon that help sustain other life-forms.

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