Tag Archives: Scripps Institution of Oceanography

Archaeomagnetism, anomalies in space, and 3,000-year-old Babylonian bricks

While i don’t usually cover the topic of magnetic fields, this fascinating research required a combination of science and the humanities, a topic of some interest to me. First, there’s the news and then excerpts from Rae Hodge’s December 25, 2023 commentary “How 3,000-year-old Babylonian tablets help scientists unravel one of the weirdest mysteries in space” for Salon.

A December 19, 2023 University College London (UCL; also on EurekAlert but published December 18, 2023) explains how Babylonian artefacts led to a discovery about earth’s magnetic fields,

Ancient bricks inscribed with the names of Mesopotamian kings have yielded important insights into a mysterious anomaly in Earth’s magnetic field 3,000 years ago, according to a new study involving UCL researchers.

The research, published in the Proceedings of the National Academy of Sciences (PNAS), describes how changes in the Earth’s magnetic field imprinted on iron oxide grains within ancient clay bricks, and how scientists were able to reconstruct these changes from the names of the kings inscribed on the bricks.

The team hopes that using this “archaeomagnetism,” which looks for signatures of the Earth’s magnetic field in archaeological items, will improve the history of Earth’s magnetic field, and can help better date artefacts that they previously couldn’t.

Co-author Professor Mark Altaweel (UCL Institute of Archaeology) said: “We often depend on dating methods such as radiocarbon dates to get a sense of chronology in ancient Mesopotamia. However, some of the most common cultural remains, such as bricks and ceramics, cannot typically be easily dated because they don’t contain organic material. This work now helps create an important dating baseline that allows others to benefit from absolute dating using archaeomagnetism.”

The Earth’s magnetic field weakens and strengthens over time, changes which imprint a distinct signature on hot minerals that are sensitive to the magnetic field. The team analysed the latent magnetic signature in grains of iron oxide minerals embedded in 32 clay bricks originating from archaeological sites throughout Mesopotamia, which now overlaps with modern day Iraq. The strength of the planet’s magnetic field was imprinted upon the minerals when they were first fired by the brickmakers thousands of years ago.

At the time they were made, each brick was inscribed with the name of the reigning king which archaeologists have dated to a range of likely timespans. Together, the imprinted name and the measured magnetic strength of the iron oxide grains offered a historical map of the changes to the strength of the Earth’s magnetic field.

The researchers were able to confirm the existence of the “Levantine Iron Age geomagnetic Anomaly,” a period when Earth’s magnetic field was unusually strong around modern Iraq between about 1050 to 550 BCE for unclear reasons. Evidence of the anomaly has been detected as far away as China, Bulgaria and the Azores, but data from within the southern part of the Middle East itself had been sparse.

Lead author Professor Matthew Howland of Wichita State University said: “By comparing ancient artefacts to what we know about ancient conditions of the magnetic field, we can estimate the dates of any artifacts that were heated up in ancient times.”

To measure the iron oxide grains, the team carefully chipped tiny fragments from broken faces of the bricks and used a magnetometer to precisely measure the fragments.

By mapping out the changes in Earth’s magnetic field over time, this data also offers archaeologists a new tool to help date some ancient artefacts. The magnetic strength of iron oxide grains embedded within fired items can be measured and then matched up to the known strengths of Earth’s historic magnetic field. The reigns of kings lasted from years to decades, which offers better resolution than radiocarbon dating which only pinpoints an artefact’s date to within a few hundred years.

An additional benefit of the archaeomagnetic dating of the artefacts is it can help historians more precisely pinpoint the reigns of some of the ancient kings that have been somewhat ambiguous. Though the length and order of their reigns is well known, there has been disagreement within the archaeological community about the precise years they took the throne resulting from incomplete historical records. The researchers found that their technique lined up with an understanding of the kings’ reigns known to archaeologists as the “Low Chronology”.

The team also found that in five of their samples, taken during the reign of Nebuchadnezzar II from 604 to 562 BCE, the Earth’s magnetic field seemed to change dramatically over a relatively short period of time, adding evidence to the hypothesis that rapid spikes in intensity are possible.

Co-author Professor Lisa Tauxe of the Scripps Institution of Oceanography (US) said: “The geomagnetic field is one of the most enigmatic phenomena in earth sciences. The well-dated archaeological remains of the rich Mesopotamian cultures, especially bricks inscribed with names of specific kings, provide an unprecedented opportunity to study changes in the field strength in high time resolution, tracking changes that occurred over several decades or even less.”

The research was carried out with funding from the U.S.-Israel Binational Science Foundatio

Here’s a link to and a citation for the paper,

Exploring geomagnetic variations in ancient Mesopotamia: Archaeomagnetic study of inscribed bricks from the 3rd–1st millennia BCE by Matthew D. Howland, Lisa Tauxe, Shai Gordin, and Erez Ben-Yosef. PNAS (Proceedings of the National Academy of Sciences) December 18, 2023 120 (52) e2313361120 DOI: https://doi.org/10.1073/pnas.2313361120

This paper is behind a paywall.

The Humanities and their importance to STEM (science, technology, engineering, and mathematics)

Rae Hodge’s December 25, 2023 commentary explains why magnetic fields might be of interest to a member of the general public (that’s me) and more about the interdisciplinarity, which drove the project, Note 1: This is a US-centric view but the situation in Canada (and I suspect elsewhere) is similar. Note 2: Links have been removed,

Among the most enigmatic mysteries of modern science are the strange anomalies which appear from time to time in the earth’s geomagnetic field. It can seem like the laws of physics behave differently in some places, with unnerving and bizarre results — spacecraft become glitchy, the Hubble Space Telescope can’t capture observations and satellite communications go on the fritz. Some astronauts orbiting past the anomalies report blinding flashes of light and sudden silence. They call one of these massive, growing anomalies the Bermuda Triangle of space — and even NASA [US National Aeronautics and Space Administration] is now tracking it. 

With all the precisely tuned prowess of modern tech turning its eye toward these geomagnetic oddities, you might not expect that some key scientific insights about them could be locked inside a batch of 3,000-year-old Babylonian cuneiform tablets. But that’s exactly what a recently published study in Proceedings of the National Academy of Sciences suggests. 

This newly discovered connection between ancient Mesopotamian writing and modern physics is more than an amusing academic fluke. It highlights just how much is at stake for 21st-century scientific progress when budget-slashing lawmakers, university administrators and private industry investors shovel funding into STEM field development while neglecting — and in some case, actively destroying — the humanities.

… Despite advances in the past five years or so, archaeomagnetism is still methodologically complex and often tedious work, often cautious data sifting to arrive at accurate interpretations. The more accurate of which come from analyzing layers upon layers of strata. 

But when combined with the expertise of the humanities — from historians and linguists, to religious scholars and anthropologists? Archaeomagnetism opens up new worlds of study across all disciplines. 

In fact, the team’s results show that the strength of the magnetic field in Mesopotamia was more than one and a half times stronger than it is in the area today, with a massive spike happening sometimes between 604 B.C. and 562 B.C. By combining the results of archaeomagnetic tests and the transcriptions of ancient languages on the bricks, the team was able to confirm this spike likely occurred during the reign of Nebuchadnezzar II.

Hand in hand with the sciences, the LIAA [Levantine Iron Age Anomaly] trail was illuminated by historical accounts of descriptively similar events, recorded from ancient authors as far west as the Iberian peninsula and well into Asia. Archaeomagnetism has now allowed researchers to not only confirm the presence of the LIAA in ancient Mesopotamia from 1050 to 550 B.C. — itself a first for science — but offers cultural historians a new way to verify and apply context to a vast tide of early scientific information.

Hodge further explores the importance of interdisciplinary work, December 25, 2023 commentary, Note: Links have been removed,

The symbiotic interdependence between the humanities and sciences deepens further in the thicket of time when one considers that the original locations of the team’s fragments likely include the earliest known centers of astrology and mathematics in Sumeria, such as Nineveh near modern-day Mosul, Iraq. At the ancient city’s royal library of the Assyrian Empire, a site dating back to around 650 B.C., a trove of thousands of tablets were excavated in the mid-1800s containing precise astronomical data surpassing that found in any previous discovery.

Among those, the “The Plough Star” tablets bear inscriptions dating to 687 B.C. and are the first known instances of humans tracking lunar and planetary orbits through both the solar ecliptic and 17 constellations. The same trove yielded the awe-striking collection known as the Astronomical Diaries, currently held in the Ashmolean Museum at Oxford, originating from near modern-day Baghdad. The oldest of which dates to 652 B.C. The latest, 61 B.C.

Hermann Hunger and David Pingree, the foremost historians on their excavation, minced no words on their value to to modern science. 

“That someone in the middle of the eighth century BC conceived of such a scientific program and obtained support for it is truly astonishing; that it was designed so well is incredible; and that it was faithfully carried out for 700 years is miraculous,” they wrote.  

In his 2021 book, “A Scheme of Heaven,” data scientist Alexander Boxer cites the two historians and observes that the “enormity of this achievement” lay in the diaries’ preservation of a snapshot of celestial knowledge of the age which — paired with accounts of weather patterns, river water tables, grain prices and even political news — allow us to pinpoint historical events from thousands of years ago, in time-windows as narrow as just a day or two.

“Rivaled only by the extraordinary astronomical records from ancient China, the Babylonian Astronomical Diaries are one of, if not the longest continuous research program ever undertaken,” writes Boxer. 

The cuneiform tablets studied by the UCL team extend this interdisciplinary legacy of the sciences and humanities beautifully by allowing us to read not only the celestially relevant data of geomagnetic history, but by reaffirming the importance of early cultural studies. One fragment, for instance, is dedicated by Nebuchadnezzar II to a temple in Larsa. The site was devoted to carrying out astrological divination traditions, and it’s where we get our earliest clue about the authorship of the Astronomical Diaries. 

Charmingly, that clue appears in the court testimony of a temple official who gets scolded for sounding a false-alarm about an eclipse, embarrassing the temple scholars in front of the whole city.

These Neo-Assyrian and Old Babylonian astrologers gave us more than antics, though. In further records at Nineveh, they would ultimately help researchers at the University of Tsukuba [Japan] — some 2,700 years later — track what were likely massive solar magnetic storms in the area, enabled by geomagnetic disruptions that may be yet linked to the LIAA.

In their dutifully recorded daily observations, one astrologer records a “red cloud” while another tablet-writer observes that “red covers the sky” in Babylon.

“These were probably manifestations of what we call today stable auroral red arcs, consisting of light emitted by electrons in atmospheric oxygen atoms after being excited by intense magnetic fields,” the authors said. “These findings allow us to recreate the history of solar activity a century earlier than previously available records…This research can assist in our ability to predict future solar magnetic storms, which may damage satellites and other spacecraft.”

Hodge ends with an observation, from her December 25, 2023 commentary,

When universities short sell the arts and humanities, we humanities students might lose our poetry, but we can write more. The science folk, on the other hand, might cost themselves another 75 years of research and $70 billion in grants trying to re-invent the Babylonian wheel because the destruction of its historical blueprint was “an arts problem.”

If you have time, do read Hodge’s December 25, 2023 commentary.

They glow under stress: soft, living materials made with algae

Caption: These soft, living materials glow in response to mechanical stress, such as compression, stretching or twisting. Credit: UC San Diego Jacobs School of Engineering

An October 20, 2023 news item on phys.org describes research into bioluminescent materials, Note: A link has been removed,

A team of researchers led by the University of California San Diego has developed soft yet durable materials that glow in response to mechanical stress, such as compression, stretching or twisting. The materials derive their luminescence from single-celled algae known as dinoflagellates.

The work, inspired by the bioluminescent waves observed during red tide events at San Diego’s beaches, was published Oct. 20 [2023] in Science Advances.

An October 23, 2023 University of California at San Diego news release (also on EurekAlert but published October 20, 2023) by Liezel Labios, which originated the news item, delves further into the research,

An exciting feature of these materials is their inherent simplicity—they need no electronics, no external power source,” said study senior author Shengqiang Cai, a professor of mechanical and aerospace engineering at the UC San Diego Jacobs School of Engineering. “We demonstrate how we can harness the power of nature to directly convert mechanical stimuli into light emission.”

This study was a multi-disciplinary collaboration involving engineers and materials scientists in Cai’s lab, marine biologist Michael Latz at UC San Diego’s Scripps Institution of Oceanography, and physics professor Maziyar Jalaal at University of Amsterdam.

The primary ingredients of the bioluminescent materials are dinoflagellates and a seaweed-based polymer called alginate. These elements were mixed to form a solution, which was then processed with a 3D printer to create a diverse array of shapes, such as grids, spirals, spiderwebs, balls, blocks and pyramid-like structures. The 3D-printed structures were then cured as a final step.

When the materials are subjected to compression, stretching or twisting, the dinoflagellates within them respond by emitting light. This response mimics what happens in the ocean, when dinoflagellates produce flashes of light as part of a predator defense strategy. In tests, the materials glowed when the researchers pressed on them and traced patterns on their surface. The materials were even sensitive enough to glow under the weight of a foam ball rolling on their surface.

The greater the applied stress, the brighter the glow. The researchers were able to quantify this behavior and developed a mathematical model that can predict the intensity of the glow based on the magnitude of the mechanical stress applied.

The researchers also demonstrated techniques to make these materials resilient in various experimental conditions. To reinforce the materials so that they can bear substantial mechanical loads, a second polymer, poly(ethylene glycol) diacrylate, was added to the original blend. Also, coating the materials with a stretchy rubber-like polymer called Ecoflex provided protection in acidic and basic solutions. With this protective layer, the materials could even be stored in seawater for up to five months without losing their form or bioluminescent properties.

Another beneficial feature of these materials is their minimal maintenance requirements. To keep working, the dinoflagellates within the materials need periodic cycles of light and darkness. During the light phase, they photosynthesize to produce food and energy, which are then used in the dark phase to emit light when mechanical stress is applied. This behavior mirrors the natural processes at play when the dinoflagellates cause bioluminescence in the ocean during red tide events. 

“This current work demonstrates a simple method to combine living organisms with non-living components to fabricate novel materials that are self-sustaining and are sensitive to fundamental mechanical stimuli found in nature,” said study first author Chenghai Li, a mechanical and aerospace engineering Ph.D. candidate in Cai’s lab.

The researchers envision that these materials could potentially be used as mechanical sensors to gauge pressure, strain or stress. Other potential applications include soft robotics and biomedical devices that use light signals to perform treatment or controlled drug release.

However, there is much work to be done before these applications can be realized. The researchers are working on further improving and optimizing the materials.

Here’s a link to and a citation for the paper,

Ultrasensitive and robust mechanoluminescent living composites by Chenghai Li, Nico Schramma, Zijun Wang, Nada F. Qari, Maziyar Jalaal, Michael I. Latz, and Shengqiang Cai. Science Advances 20 Oct 2023 Vol 9, Issue 42 DOI: 10.1126/sciadv.adi8643

This paper is open access.

Australian peacock spiders, photonic nanostructures, and making money

Researcher Bor-Kai Hsiung’s work has graced this blog before but the topic was tarantulas and their structural colour. This time, it’s all about Australian peacock spiders and their structural colour according to a December 22, 2017 news item on ScienceDaily,

Even if you are arachnophobic, you probably have seen pictures or videos of Australian peacock spiders (Maratus spp.). These tiny spiders are only 1-5 mm long but are famous for their flamboyant courtship displays featuring diverse and intricate body colorations, patterns, and movements.

The spiders extremely large anterior median eyes have excellent color vision and combine with their bright colors to make peacock spiders cute enough to cure most people of their arachnophobia. But these displays aren’t just pretty to look at, they also inspire new ways for humans to produce color in technology.

One species of peacock spider — the rainbow peacock spider (Maratus robinsoni) is particularly neat, because it showcases an intense rainbow iridescent signal in males’ courtship displays to the females. This is the first known instance in nature of males using an entire rainbow of colors to entice females. Dr. Bor-Kai Hsiung led an international team of researchers from the US (UAkron, Cal Tech, UC San Diego, UNL [University of Nebraska-Lincoln]), Belgium (Ghent University), Netherlands (UGroningen), and Australia to discover how rainbow peacock spiders produce this unique multi-color iridescent signal.

A December 22, 2017 Ghent University (Belgium) press release on Alpha Galileo, which originated the news item, provides more technical detail,

Using a diverse array of research techniques, including light and electron microscopy, hyperspectral imaging, imaging scatterometry, nano 3D printing and optical modeling, the team found the origin of this intense rainbow iridescence emerged from specialized abdominal scales of the spiders. These scales have an airfoil-like microscopic 3D contour with nanoscale diffraction grating structures on the surface.

The interaction between the surface nano-diffraction grating and the microscopic curvature of the scales enables separation and isolation of light into its component wavelengths at finer angles and smaller distances than are possible with current manmade engineering technologies.

Inspiration from these super iridescent scales can be used to overcome current limitations in spectral manipulation, and to further reduce the size of optical spectrometers for applications where fine-scale spectral resolution is required in a very small package, notably instruments on space missions, or wearable chemical detection systems. And it could have a wide array of implications to fields ranging from life sciences and biotechnologies to material sciences and engineering.

Here’s a video of an Australian rainbow peacock spider,

Here’s more from the YouTube description published on April 13, 2017 by Peacockspiderman,

Scenes of Maratus robinsoni, a spider Peter Robinson discovered and David Hill and I named it after him in 2012. You can read our description on pages 36-41 in Peckhamia 103.2, which can be downloaded from the Peckhamia website http://peckhamia.com/peckhamia_number…. This is one of the two smallest species of peacock spider (2.5 mm long) and the only spider we know of in which colour changes occur every time it moves, this video was created to document this. Music: ‘Be Still’ by Johannes Bornlöf licensed through my MCN ‘Brave Bison’ from ‘Epidemic Sound’ For licensing inquiries please contact Brave Bison licensing@bravebison.io

The University of California at San Diego also published a December 22, 2017 news release about this work, which covers some of the same ground while providing a few new tidbits of information,

Brightly colored Australian peacock spiders (Maratus spp.) captivate even the most arachnophobic viewers with their flamboyant courtship displays featuring diverse and intricate body colorations, patterns, and movements – all packed into miniature bodies measuring less than five millimeters in size for many species. However, these displays are not just pretty to look at. They also inspire new ways for humans to produce color in technology.

One species of peacock spider – the rainbow peacock spider (Maratus robinsoni) – is particularly impressive, because it showcases an intense rainbow iridescent signal in males’ courtship displays to females. This is the first known instance in nature of males using an entire rainbow of colors to entice females to mate. But how do males make their rainbows? A new study published in Nature Communications looked to answer that question.

Figuring out the answers was inherently interdisciplinary so Bor-Kai Hsiung, a postdoctoral scholar at Scripps Institution of Oceanography at the University of California San Diego, assembled an international team that included biologists, physicists and engineers. Starting while he was a Ph.D. student at The University of Akron under the mentorship of Todd Blackledge and Matthew Shawkey, the team included researchers from UA, Scripps Oceanography, California Institute of Technology, and University of Nebraska-Lincoln, the University of Ghent in Belgium, University of Groningen in Netherlands, and Australia to discover how rainbow peacock spiders produce this unique iridescent signal.

The team investigated the spider’s photonic structures using techniques that included light and electron microscopy, hyperspectral imaging, imaging scatterometry and optical modeling to generate hypotheses about how the spider’s scale generate such intense rainbows. The team then used cutting-edge nano 3D printing to fabricate different prototypes to test and validate their hypotheses. In the end, they found that the intense rainbow iridescence emerged from specialized abdominal scales on the spiders. These scales combine an airfoil-like microscopic 3D contour with nanoscale diffraction grating structures on the surface. It is the interaction between the surface nano-diffraction grating and the microscopic curvature of the scales that enables separation and isolation of light into its component wavelengths at finer angles and smaller distances than are possible with current engineering technologies.

“Who knew that such a small critter would create such an intense iridescence using extremely sophisticated mechanisms that will inspire optical engineers,” said Dimitri Deheyn, Hsuing’s advisor at Scripps Oceanography and a coauthor of the study.

For Hsiung, the finding wasn’t quite so unexpected.

“One of the main questions that I wanted to address in my Ph.D. dissertation was ‘how does nature modulate iridescence?’ From a biomimicry perspective, to fully understand and address a question, one has to take extremes from both ends into consideration. I purposefully chose to study these tiny spiders with intense iridescence after having investigated the non-iridescent blue tarantulas,” said Hsiung.

The mechanism behind these tiny rainbows may inspire new color technology, but would not have been discovered without research combining basic natural history with physics and engineering, the researchers said.

“Nanoscale 3D printing allowed us to experimentally validate our models, which was really exciting,” said Shawkey. “We hope that these techniques will become common in the future.”

“As an engineer, what I found fascinating about these spider structural colors is how these long evolved complex structures can still outperform human engineering,” said Radwanul Hasan Siddique, a postdoctoral scholar at Caltech and study coauthor. “Even with high-end fabrication techniques, we could not replicate the exact structures. I wonder how the spiders assemble these fancy structural patterns in the first place!”

Inspiration from these super iridescent spider scales can be used to overcome current limitations in spectral manipulation, and to reduce the size of optical spectrometers for applications where fine-scale spectral resolution is required in a very small package, notably instruments on space missions, or wearable chemical detection systems.

In the end, peacock spiders don’t just produce nature’s smallest rainbows.They could also have implications for a wide array of fields ranging from life sciences and biotechnologies to material sciences and engineering.

Before citing the paper and providing a link, here’s a story by Robert F. Service for Science magazine about attempts to capitalize on ‘spider technology’, in this case spider silk,

The hype over spider silk has been building since 1710. That was the year François Xavier Bon de Saint Hilaire, president of the Royal Society of Sciences in Montpellier, France, wrote to his colleagues, “You will be surpriz’d to hear, that Spiders make a Silk, as beautiful, strong and glossy, as common Silk.” Modern pitches boast that spider silk is five times stronger than steel yet more flexible than rubber. If it could be made into ropes, a macroscale web would be able to snare a jetliner.

The key word is “if.” Researchers first cloned a spider silk gene in 1990, in hopes of incorporating it into other organisms to produce the silk. (Spiders can’t be farmed like silkworms because they are territorial and cannibalistic.) Today, Escherichia coli bacteria, yeasts, plants, silkworms, and even goats have been genetically engineered to churn out spider silk proteins, though the proteins are often shorter and simpler than the spiders’ own. Companies have managed to spin those proteins into enough high-strength thread to produce a few prototype garments, including a running shoe by Adidas and a lightweight parka by The North Face. But so far, companies have struggled to mass produce these supersilks.

Some executives say that may finally be about to change. One Emeryville, California-based startup, Bolt Threads, says it has perfected growing spider silk proteins in yeast and is poised to turn out tons of spider silk thread per year. In Lansing, Michigan, Kraig Biocraft Laboratories says it needs only to finalize negotiations with silkworm farms in Vietnam to produce mass quantities of a combination spider/silkworm silk, which the U.S. Army is now testing for ballistics protection. …

I encourage you to read Service’s article in its entirety if the commercialization prospects for spider silk interest you as it includes gems such as this,

Spider silk proteins are already making their retail debut—but in cosmetics and medical devices, not high-strength fibers. AMSilk grows spider silk proteins in E. coli and dries the purified protein into powders or mixes it into gels, for use as additives for personal care products, such as moisture-retaining skin lotions. The silk proteins supposedly help the lotions form a very smooth, but breathable, layer over the skin. Römer says the company now sells tons of its purified silk protein ingredients every year.

Finally, here’s a citation for and a link to the paper about Australian peacock spiders and nanophotonics,

Rainbow peacock spiders inspire miniature super-iridescent optics by Bor-Kai Hsiung, Radwanul Hasan Siddique, Doekele G. Stavenga, Jürgen C. Otto, Michael C. Allen, Ying Liu, Yong-Feng Lu, Dimitri D. Deheyn, Matthew D. Shawkey, & Todd A. Blackledge. Nature Communications 8, Article number: 2278 (2017) doi:10.1038/s41467-017-02451-x Published online: 22 December 2017

This paper is open access.

As for Bor-Kai Hsiung’s other mentions here:

How tarantulas get blue (December 7, 2015 posting)

Noniridescent photonics inspired by tarantulas (October 19, 2016 posting)

More on the blue tarantula noniridescent photonics (December 28, 2016 posting)

How tarantulas get blue

Cobalt Blue Tarantula [downloaded from http://www.tarantulaguide.com/tarantula-pictures/cobalt-blue-tarantula-4/]

Cobalt Blue Tarantula [downloaded from http://www.tarantulaguide.com/tarantula-pictures/cobalt-blue-tarantula-4/]

That’s a stunning shade of blue on the tarantula and now scientists can explain why these and other ‘spiders’ are sometimes blue, from a Nov. 30, 2015 news item on ScienceDaily,

Scientists recently discovered that tiny, multilayer nanostructures inside a tarantula’s hair are responsible for its vibrant color. The science behind how these hair-raising spiders developed their blue hue may lead to new ways to improve computer or TV screens using biomimicry.

A Nov. 30, 2015 University of California at San Diego news release by Annie Reisewitz, which originated the news item, explains more,

Researchers from Scripps Institution of Oceanography at UC San Diego and University of Akron found that many species of tarantulas have independently evolved the ability to grow blue hair using nanostructures in their exoskeletons, rather than pigments. The study, published in the Nov. 27 issue of Science Advances, is the first to show that individual species evolved separately to make the same shade of a non-iridescent color, one that doesn’t change when viewed at different angles.

Since tarantulas’ blue color is not iridescent, the researchers suggest that the same process can be applied to make pigment replacements that never fade and help reduce glare on wide-angle viewing systems in phones, televisions, and other devices.

“There is strikingly little variety in the shade of blue produced by different species of tarantulas,” said Dimitri Deheyn, a Scripps Oceanography researcher studying marine and terrestrial biomimicry and coauthor of the study. “We see that different types of nanostructures evolved to produce the same ‘blue’ across distant branches of the tarantula family tree in a way that uniquely illustrates natural selection through convergent evolution.”

Unlike butterflies and birds that use nanostructures to produce vibrant colors to attract the attention of females during display courtship, tarantulas have poor vision and likely evolved this trait for a different reason. While the researchers still don’t understand the benefits tarantulas receive from being blue, they are now investigating how to reproduce the tarantula nanostructures in the laboratory.

The tarantula study is just one example of the biomimicry research being conducted in the Deheyn lab at Scripps Oceanography. In a cover article in the Nov. 10 of Chemistry of Materials, Deheyn and colleagues published new findings on the nanostructure of ragweed pollen, which shows interesting optical properties and has possible biomimicry applications. By transforming the pollen into a magnetic material with a specialized coating to give it more or less reflectance, the particle could adhere in a similar way that pollen does in nature while being able to adjust its visibility. The researchers suggest this design could be applied to create a new type of tagging or tracking technology.

Using a high-powered microscope, known as a hyperspectral imaging system, Deheyn is able to map a species’ color field pixel by pixel, which correlates to the shape and geometry of the nanostructures and gives them their unique color.

“This unique technology allows us to associate structure with optical property,” said Deheyn. “Our inspiration is to learn about how nature evolves unique traits that we could mimic to benefit future technologies.”

Here’s a link to and a citation for the paper,

Blue reflectance in tarantulas is evolutionarily conserved despite nanostructural diversity by Bor-Kai Hsiung, Dimitri D. Deheyn, Matthew D. Shawkey, and Todd A. Blackledge. Science Advances  27 Nov 2015: Vol. 1, no. 10, e1500709 DOI: 10.1126/sciadv.1500709

This paper appears to be open access.