The Geomagnetic Field and Us
Watch The First Ever Recording of a Magnetic Field's Affect on a Cell
Quick note: There’s a Subscribe button thisaway↗. If you like the piece here and find yourself desirous of more signature infinite frontiersmanship, give it a little tiptap. It would mean the world and all the holograms therein to me. Thanks!
Since the 70s, researchers have suspected that because magnets can attract and repel electrons, Earth’s magnetic field might also influence animal behavior. A breakthrough study of monarch butterfly migration in the mid-teens brought us closer to an understanding of the magnetoreception phenomenon. Then, this January, a study out of Japan was able to capture the first ever observation of a magnetic field affecting a living cell. This is one of those glorious moments in science when folks who thought it get to say we knew it!
The Butterfly Effect
In June of 2014, a flutter of articles were published proclaiming that monarch butterflies use a biological magnetic compass to guide their migration. The tidal wave of Lepidoptera appreciation originated from an exhaustive study in the journal Nature.
Up until that point it was known that monarchs use antenna-based time-compensated sun compasses to navigate their journey. Their eyes sense directional daylight which dishes the info to the sun compass found in the central complex area which cross-references the data with anneal circadian clocks. It‘s basically like a built-in biological sundial.
What’s flummoxed scientists is that even on cloudy days monarchs keep a steady course. The new discovery found that the butterflies have a second inclination compass that uses light in the ultraviolet-A/blue spectral range. They are able to follow this range using light-sensitive magnetosensors on their antennae.
The researchers tested what was was then an hypothesis, by placing butterflies in a flight simulator. They surrounded the chamber with a magnetic coil system and varied the inclination angle of the field to create an artificial equator and poles. The monarchs followed along with almost perfect precision.
White Hot Burning Cryptochrome
The suspicion of the 2014 report was that the monarch's compass is mediated by molecules in the antennae knows as cryptochromes which are sensitive to both light and magnetic fields. If you want to get real nerdy (and trust you me we do!), crytpochromes are a class of flavoproteins sensitive to blue light. Select plants, insects and mammals all have them. The two genes Cry1 and Cry2 code for the two cryptochrome proteins CRY1 and CRY2. When exposed to blue light cryptochome proteins form radical pairs. This is caused by an electron jumping from one molecule to another, in so doing creating two molecules with single electrons. This produces a spinning effect, which can create chemical reactions. More on this in a bit. In the meantime, feast your eyes on these Cryptobois and what a fantastic time they seem to be having.
Then, a Burst of Light
While the the 2014 butterfly study provided extraordinary proof of magnetoreceptivity, the findings were relied largely on indirect evidence. Up until this month, no researcher has successfully measured chemical reactions inside a living cell changing directly because of a magnetic field.
The two researchers - Professor Jonathan Woodward from the University of Tokyo and his doctoral student Noboru Ikeya - started with the flavin molecules in human cervical cancer cells. Flavins are a subunit of cryptochromes. When exposed to blue light, flavins either fluoresce or produce radical pairs. This is caused by the molecules spinning in the same or opposite direction. It’s sort of a competition between the two reactions. The radical pairs don’t react fast enough and the flavins produce a lot of fluorescence; the radical pairs move swiftly and the fluorescence is dimmer. With a custom-built microscope in place, the researchers then deployed a magnetic field equivalent to the power of a fridge magnet over the flavins to gauge the reaction and hopefully record it.
The cells were blasted with with blue light which caused them to fluoresce for 40 seconds. Researchers then swept a magnetic field over the cells every four seconds and measured changes in the intensity of the fluorescence. The cell’s dimmed by about 3.5% each time the magnetic field swept over the cells. The recording is truly glorious.
The study cracks open an entire new line of inquiry into the earth’s geomagnetic field and its effects on organisms. The proof will yield both effective ways of interpreting the world around us and concerns about the impact of technology we’ve built on the living world.
Stay tuned, not that you have a choice.
But also you do…