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The mystery of how birds navigate is over, and the answer is so amazing
It’s the first time magnetoreception has been discovered in animals, researchers claim.

One of the longest running mysteries is exactly how birds navigate when they fly south for the winter or back come spring. For forty years, scientists have known that birds can somehow sense the magnetic field and navigate by it. But they’ve been unable to figure out how, until now. Two teams have recently identified that birds can actually visualize the magnetosphere.
One study comes out of the University of Oldenburg, in Germany, where researchers studied European robins. The other is from Lund University, in Sweden, where scientists examined zebra finches. For a long time, the prevailing theory was that cells rich in iron in bird’s beaks aided their navigation. Then, in the late 1960s, Klaus Schulten of the University of Illinois proposed that migratory animals, including birds, must contain a certain molecule in their eyes or brains that responds to the magnetic field.
Evidence since has mounted towards Schulten’s hypothesis. Now it seems, these two teams have made it the prevailing theory. The Swedish study was published in the Journal of the Royal Society Interface, while the German one was published in Current Biology. Both studies focus on a class of proteins known as cryptochromes.
Certain molecules in birds’ eyes help them to see the magnetic field and navigate by it. Credit: Getty Images.
Each team discovered a particular type of cryptochrome protein in birds’ retinas known as Cry4, which is sensitive to blue light—including that given off by the Earth’s magnetic field. Both plants and animals are known to contain photoreceptive cells that respond to blue light, which are necessary for circadian rhythms. Yet, this is the first time magnetoreception has been discovered in animals.
A bird’s visual magnetic detection cells rely on quantum coherence. It’s interactions with the quantum field that allows migratory birds to navigate, according to biologist Atticus Pinzon-Rodriguez, at Lund University. Recent research indicated three possible cryptochromes, Cry1, Cry2, and Cry 4, may be involved. Scientists in both teams looked at the gene expression associated with each protein.
This is the first time magnetoreception has been discovered in animals. But how is the magnetic field perceived by birds? Credit: Getty Images.
They found that Cry1 and Cry2 expression fluctuated throughout the day—as they’re both tied to circadian rhythms, Cry 4 didn’t. It stayed constant. As this gene's protein is being consistently produced, researchers believe it’s tied to detecting the magnetic field. Consider that birds navigate by it day or night. There are other indicators too. European robins for instance, were shown to have increased Cry4 expression during the migratory season, something that wasn’t found in chickens.
Both teams, in addition to looking at gene expression, found that the area in the birds’ retinas where Cry4 is located receives a lot of light. Though the evidence is compelling and the theory strong, more research must be done, particularly in bird species with latent Cry4, in order to confirm these results. And beyond that, scientists if they prove the theory true, will then have to discern exactly how birds perceive the magnetic field.
To learn more about the science behind migratory animals, click here:
What is the purpose of universities?
For centuries, universities have advanced humanity toward truth. Professor Jonathan Haidt speaks to why college campuses are suddenly heading in the opposite direction.
Left: Professor Jonathan Haidt. Right: Artistotle.
- In a lecture at UCCS, NYU professor Jonathan Haidt considers the 'telos' or purpose of universities: To discover truth.
- Universities that prioritize the emotional comfort of students over the pursuit of truth fail to deliver on that purpose, at a great societal cost.
- To make that point, Haidt quotes CNN contributor Van Jones: "I don't want you to be safe ideologically. I don't want you to be safe emotionally. I want you to be strong—that's different."
CNN contributor Van Jones speaks onstage at the EMA IMPACT Summit in 2018.
Credit: Michael Kovac/Getty Images for Environmental Media Association
<p>There are many places and institutions whose purpose, or <em>telos</em>, is comfort. But a university is not one of those places. To make that point, Haidt quotes CNN contributor Van Jones:</p><p style="margin-left: 20px;">I don't want you to be safe ideologically. I don't want you to be safe emotionally. I want you to be strong—that's different. I'm not going to pave the jungle for you. Put on some boots and learn how to deal with adversity. I'm not going to take all the weights out of the gym. That's the whole point of the gym. <em>This</em> is the gym.</p><p>By prioritizing comfort over the pursuit of truth, universities are ignoring their purpose. Higher education should be an arena of open inquiry and free expression, where ideas are exchanged, tested, and scrutinized. A liberal education should be "an invitation to be concerned not with the employment of what is familiar but with understanding what is not yet understood," <a href="https://books.google.com/books?id=Jpu7BAAAQBAJ&pg=PT286&lpg=PT286&dq=%22an+invitation+to+be+concerned+not+with+the+employment+of+what+is+familiar+but+with+understanding+what+is+not+yet+understood.%E2%80%9D&source=bl&ots=bmqaS1BxSm&sig=ACfU3U0aOokPZOGJlLFUVO9-a8VBV50tCw&hl=en&sa=X&ved=2ahUKEwi_u-jd1_btAhWqzVkKHSdKBMsQ6AEwAnoECAEQAg#v=onepage&q=%22an%20invitation%20to%20be%20concerned%20not%20with%20the%20employment%20of%20what%20is%20familiar%20but%20with%20understanding%20what%20is%20not%20yet%20understood.%E2%80%9D&f=false" target="_blank">according</a> to philosopher Michael Oakeshott.</p>You might also like:
<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="d1a3bbdeaba1ed201e5892b6a2ccbfb5"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/IoXpNJLFngc?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span>Octopus-like creatures inhabit Jupiter’s moon, claims space scientist
A leading British space scientist thinks there is life under the ice sheets of Europa.
Jupiter's moon Europa has a huge ocean beneath its sheets of ice.
- A British scientist named Professor Monica Grady recently came out in support of extraterrestrial life on Europa.
- Europa, the sixth largest moon in the solar system, may have favorable conditions for life under its miles of ice.
- The moon is one of Jupiter's 79.
Neil deGrasse Tyson wants to go ice fishing on Europa
<div class="rm-shortcode" data-media_id="GLGsRX7e" data-player_id="FvQKszTI" data-rm-shortcode-id="f4790eb8f0515e036b24c4195299df28"> <div id="botr_GLGsRX7e_FvQKszTI_div" class="jwplayer-media" data-jwplayer-video-src="https://content.jwplatform.com/players/GLGsRX7e-FvQKszTI.js"> <img src="https://cdn.jwplayer.com/thumbs/GLGsRX7e-1920.jpg" class="jwplayer-media-preview" /> </div> <script src="https://content.jwplatform.com/players/GLGsRX7e-FvQKszTI.js"></script> </div>Water Vapor Above Europa’s Surface Deteced for First Time
<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="9c4abc8473e1b89170cc8941beeb1f2d"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/WQ-E1lnSOzc?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span>From NASA to your table: A history of food from thin air
A fairly old idea, but a really good one, is about to hit the store shelves.
- The idea of growing food from CO2 dates back to NASA 50 years ago.
- Two companies are bringing high-quality, CO2-derived protein to market.
- CO2-based foods provide an environmentally benign way of producing the protein we need to live.
The basic idea
<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTQ0NTM3Ny9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYxOTc4NzE1MX0.qxFjO6GkVVEjS_VEKy4pIkrmv-gknDbBgTHourWFUcc/img.jpg?width=980" id="20397" class="rm-shortcode" data-rm-shortcode-id="fa52d13cbf404456d0a5be77ff2e091e" data-rm-shortcode-name="rebelmouse-image" data-width="1089" data-height="898" />Credit: Big Think
<p> The basic mechanism for deriving food from CO<sup>2</sup> involves a fairly simple closed-loop system that executes a process over and over in a cyclical manner, producing edible matter along the way. In space, astronauts produce carbon dioxide when they breathe, which is then captured by microbes, which then convert it into a carbon-rich material. The astronauts eat the material, breathe out more CO<sup>2</sup>, and on and on. On Earth, the CO<sup>2</sup> is captured from the atmosphere. </p>Drawing first breath
<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTQ0NTM3NS9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY0NDQyNjAwMH0.3b4FuXhLwAqGtXzFu2dw8Gec6phKp3bxkajLOJKFOYE/img.jpg?width=980" id="03d4b" class="rm-shortcode" data-rm-shortcode-id="a5131ef8090c05af83989905de39c53d" data-rm-shortcode-name="rebelmouse-image" data-width="1000" data-height="780" />Credit: NASA
<p> NASA's investigation into using CO<sup>2</sup> for food production began with a 1966 report written by R. B. Jagow and R. S. Thomas and published by Ames Research Center. The nine-chapter report was called "<a href="https://ntrs.nasa.gov/citations/19670025254" target="_blank">The Closed Life-Support System</a>." Each chapter contained a proposal for growing food on long missions. </p><p> Chapter 8, written by J. F. Foster and J. H. Litchfield of the Battelle Memorial Institute in Columbus, Ohio, proposed a system that utilized a hydrogen-fixing bacteria, <em><a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC247306/" target="_blank">Hydrogenomonas</a></em>—NASA had been experimenting with the bacteria for several years at that point—and recycled CO<sup>2</sup> in a compact, low-power, closed-loop system. The system would be able to produce edible cell matter in way that "should then be possible to maintain continuous cultures at high efficiencies for very long periods of time." </p><p> At the time, extended missions that would benefit from such a system were off in the future. </p><p> In 2019, and with its eye toward upcoming Mars missions, NASA returned to the idea, sponsoring the <a href="https://www.nasa.gov/directorates/spacetech/centennial_challenges/co2challenge/challenge-announced.html" target="_blank">CO2 Conversion Challenge</a>, "seeking novel ways to convert carbon dioxide into useful compounds." Phase 1 of the contest invited proposals for processes that could "convert carbon dioxide into glucose in order to eventually create sugar-based fuel, food, medicines, adhesives and other products." </p><p> In May 2109, NASA announced the <a href="https://www.nasa.gov/spacetech/centennial_challenges/co2challenge/winning-teams-design-systems-to-convert-carbon-dioxide-into-something-sweet.html" target="_blank">winners</a> of Phase 1. The space agency concluded acceptance of <a href="https://www.co2conversionchallenge.org/#about" target="_blank">Phase 2</a> entries on December 4, 2020.</p>Approaching the Finnish line
<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTQ0NTM2Mi9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY0MTkyNDYzNH0.02upErPyJQO5YvKEmk-Hqrve4Prg_5cZHMaXBFCAbOQ/img.jpg?width=980" id="e593a" class="rm-shortcode" data-rm-shortcode-id="e2d8de8068bcd9f497f284d2fafc7b9c" data-rm-shortcode-name="rebelmouse-image" data-width="1400" data-height="930" />Solein "meatballs"
Credit: Solar Foods
<p> We've <a href="https://bigthink.com/technology-innovation/protein-from-air?rebelltitem=1#rebelltitem1" target="_self">written previously</a> about <a href="https://solarfoods.fi" target="_blank">Solar Foods</a>, a company backed by the Finnish government who <a href="https://solarfoods.fi/our-news/business-finland-greenlights-solar-foods-e8-6m-project/" target="_blank">recently invested</a> €4.3 million to help complete the company's €8.6 million commercialization of their nutrient-rich CO<sup>2</sup>-based protein powder, <a href="https://solarfoods.fi/solein/" target="_blank">Solein</a>. The company anticipates Solein will provide protein to some 400 million meals by 2025, and has so far developed 20 different food products from it. </p>In the air tonight
<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTQ0NTM2NC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY3MjQ4MjgxMH0.6VP4Aw_JzTG7lnuQeXiUnpAppJTdnsxVTuPdiUiW9oI/img.jpg?width=980" id="4b5a0" class="rm-shortcode" data-rm-shortcode-id="9e683650fd8175592794dff6ae0799bf" data-rm-shortcode-name="rebelmouse-image" data-width="1440" data-height="894" />Air Protein taco
Credit: Air Protein
<p> Another player, <a href="https://www.airprotein.com" target="_blank">Air Protein</a>, is based in California's Bay Area and is also bringing to market their own CO<sup>2</sup> protein named after the company. The company <a href="https://www.prnewswire.com/news-releases/air-protein-introduces-the-worlds-first-air-based-food-300955972.html" target="_blank">describes</a> it as a "nutrient-rich protein with the same amino acid profile as an animal protein and packed with crucial B vitamins, which are often deficient in a vegan diet." </p><p> The company recently <a href="https://www.greenqueen.com.hk/air-protein-bags-us32m-in-series-a-to-commercialise-climate-friendly-meat/" target="_blank">secured $32 million</a> in venture-capital funding. </p><p> Although Air Protein is actually flour—like Solein—the company is positioning Air Protein as offering "the first air-based meat," while Solein was announced first, and there's <a href="https://www.afr.com/life-and-luxury/food-and-wine/company-that-makes-meat-out-of-air-attracts-big-backers-20210108-p56sk0" target="_blank" rel="noopener noreferrer">no public timetable</a> yet for the arrival of Air Protein products on store shelves. In any event, non-animal "meats" are a <a href="https://bigthink.com/technology-innovation/whopper" target="_self">hot market</a> these days with the success of Beyond Burger and Impossible Foods cruelty-free meat substitutes. </p>Striking oil
<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTQ0NTM2Ny9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY1MzE3NjA3NH0.1o05KthbzT9JokT7-0UzWDq4MiLIfXJIGfPddhLNKqk/img.jpg?width=980" id="a45ef" class="rm-shortcode" data-rm-shortcode-id="143316dcc3691fcce024e83a6cbaca3f" data-rm-shortcode-name="rebelmouse-image" data-width="1440" data-height="959" />Deforestation for palm oil
Credit: whitcomberd/Adobe Stock
<p> Though Air Protein's promotional materials emphasize meat substitutes that will be derived from their flour, a <a href="https://youtu.be/c8WMM_PUOj0" target="_blank">TED Talk</a> by company co-founder Lisa Dyson reveals another Air Protein product that could arguably have an even greater impact by potentially eliminating the need for palm oil and the deforestation it requires — their CO<sup>2</sup> process can produce oils.</p><p><span></span>The company has already created a citrus-like oil that can be used for fragrances, flavoring, as a biodegradable cleaner, and "even as a jet fuel." Perhaps more excitingly, the company has made another oil that's similar to palm oil. Since palm trees are the <a href="https://www.ran.org/palm_oil_fact_sheet" target="_blank">crop most responsible</a> for the decimation of the world's rain forests, an environmentally benign replacement for it would be a very big deal. Dyson also notes that their oils could substitute morally problematic coconut oil, whose harvesting has lately been reported to often involve the abuse of macaque monkeys.</p>Putting carbon dioxide to work
<p> We know we have too much of the stuff, so finding a way of utilizing at least some CO<sup>2</sup> to create foods and other products that reduce the need for destructive commercial practices is a solid win for humankind. Harkening back to its NASA origins, Dyson notes in her talk that Earth, too, is sort of a self-contained spaceship, albeit a big one. Finding new ways to productively reuse what it has to offer clearly benefits us all. </p>Can you step in the same river twice? Wittgenstein vs. Heraclitus
Imagine Heraclitus spending an afternoon down by the river...
Cancer cells hibernate to survive chemotherapy, finds study
Researchers discover that cancer cells go into hibernation to avoid chemotherapy effects.
