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Animal magnetism: Bacteria may help creatures sense Earth's magnetic fields
An intriguing theory explains animals' magnetic sense.
- Some animals can navigate via magnetism, though scientists aren't sure how.
- Research shows that some of these animals contain magnetotactic bacteria.
- These bacteria align themselves along the magnetic field's grid lines.
It's one of the more fascinating discoveries of the last several decades: the growing list of animals who can navigate the Earth's magnetic grid to get where they need to go. From birds to dogs, from fruit flies to lobsters, a number of species are somehow hooked into the planet's magnetic field — maybe even humans. The big unanswered question is how?
A new paper just published in Philosophical Transactions of the Royal Society B may have the answer: The creatures may have a symbiotic relationship with magnetotactic bacteria that orient them along global magnetic field lines.
While it's possible that the bacteria themselves are just one more magnetically sensitive organism, the paper presents evidence supporting the theory that their presence within other organisms endows their hosts with their magnetic navigational abilities.
Magnetotactic bacteria hosts
A right whale mother and calf
One of the paper's authors, Geneticist Robert Fitak, is affiliated with the biology department of the University of Central Florida in (UCF) Orlando. Prior to joining the department, he spent four years as a postdoctoral researcher at Duke University investigating the genomic mechanisms responsible for magnetic perception in fish and lobsters.
Fitak tells UFC Today, "The search for a mechanism has been proposed as one of the last major frontiers in sensory biology and described as if we are 'searching for a needle in a needle stack.'"
That metaphorical needle stack may well be the scientific community's largest database of microbes, the Metagenomic Rapid Annotations using Subsystems Technology database. It lists the animal samples in which magnetotactic bacteria have been found.
The primary use of the database, says Fitak, has been the measurement of bacterial diversity in entire phyla. An accounting of the appearance of magnetotactic bacteria in individual species is something that has previously be unexplored. "The presence of these magnetotactic bacteria had been largely overlooked, or 'lost in the mud' amongst the massive scale of these datasets," he reports.
Fitak dug into the database and discovered that magnetotactic bacteria have indeed been identified in a number of species known to navigate by magnetism, among them loggerhead sea turtles, Atlantic right whales, bats, and penguins. Candidatus Magnetobacterium bavaricum is regularly found in loggerheads and penguins, while Magnetospirillum and Magnetococcus are common among right whales and bats.
As for other magnetic-field-sensitive animals, he says, "I'm working with the co-authors and local UCF researchers to develop a genetic test for these bacteria, and we plan to subsequently screen various animals and specific tissues, such as in sea turtles, fish, spiny lobsters and birds."
The bacteria-host relationship
While the presence of the bacteria in these particular species is intriguing, further study is needed to be sure they're responsible for other animals' magnetic navigation. Their presence in these species could be just a coincidence.
Fitak also notes that he doesn't know at this point exactly where in the host animal the magnetotactic bacteria would reside, or other details of their symbiotic relationship. He suggests that they might be found in nervous tissue associated with navigation, such as that found in the brain or eye.
If confirmed, Fitak's hypothesis could suggest that our own sensitivity to the Earth's magnetic field might one day be enhanced via magnetotactic bacteria in our own individual microbiomes, should they be benign to us as hosts.
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"Deepfakes" and "cheap fakes" are becoming strikingly convincing — even ones generated on freely available apps.
- A writer named Magdalene Visaggio recently used FaceApp and Airbrush to generate convincing portraits of early U.S. presidents.
- "Deepfake" technology has improved drastically in recent years, and some countries are already experiencing how it can weaponized for political purposes.
- It's currently unknown whether it'll be possible to develop technology that can quickly and accurately determine whether a given video is real or fake.
The future of deepfakes<p>In 2018, Gabon's president Ali Bongo had been out of the country for months receiving medical treatment. After Bongo hadn't been seen in public for months, rumors began swirling about his condition. Some suggested Bongo might even be dead. In response, Bongo's administration released a video that seemed to show the president addressing the nation.</p><p>But the <a href="https://www.facebook.com/watch/?v=324528215059254" target="_blank">video</a> is strange, appearing choppy and blurry in parts. After political opponents declared the video to be a deepfake, Gabon's military attempted an unsuccessful coup. What's striking about the story is that, to this day, experts in the field of deepfakes can't conclusively verify whether the video was real. </p><p>The uncertainty and confusion generated by deepfakes poses a "global problem," according to a <a href="https://www.brookings.edu/research/is-seeing-still-believing-the-deepfake-challenge-to-truth-in-politics/#cancel" target="_blank">2020 report from The Brookings Institution</a>. In 2018, the U.S. Department of Defense released some of the first tools able to successfully detect deepfake videos. The problem, however, is that deepfake technology keeps improving, meaning forensic approaches may forever be one step behind the most sophisticated forms of deepfakes. </p><p>As the 2020 report noted, even if the private sector or governments create technology to identify deepfakes, they will:</p><p style="margin-left: 20px;">"...operate more slowly than the generation of these fakes, allowing false representations to dominate the media landscape for days or even weeks. "A lie can go halfway around the world before the truth can get its shoes on," warns David Doermann, the director of the Artificial Intelligence Institute at the University of Buffalo. And if defensive methods yield results short of certainty, as many will, technology companies will be hesitant to label the likely misrepresentations as fakes."</p>
Context is everything.
The COVID-19 pandemic has introduced a number of new behaviours into daily routines, like physical distancing, mask-wearing and hand sanitizing. Meanwhile, many old behaviours such as attending events, eating out and seeing friends have been put on hold.
A new study looks at how images of coffee's origins affect the perception of its premiumness and quality.
- Images can affect how people perceive the quality of a product.
- In a new study, researchers show using virtual reality that images of farms positively influence the subjects' experience of coffee.
- The results provide insights on the psychology and power of marketing.