Mix-and-match kit could enable astronauts to build a menagerie of lunar exploration bots

When astronauts begin to build a permanent base on the moon, as NASA plans to do in the coming years, they'll need help. Robots could potentially do the heavy lifting by laying cables, deploying solar panels, erecting communications towers, and building habitats. But if each robot is designed for a specific action or task, a moon base could become overrun by a zoo of machines, each with its own unique parts and protocols.

To avoid a bottleneck of bots, a team of MIT engineers is designing a kit of universal robotic parts that an astronaut could easily mix and match to rapidly configure different robot "species" to fit various missions on the moon. Once a mission is completed, a robot can be disassembled and its parts used to configure a new robot to meet a different task.

The team calls the system WORMS, for the Walking Oligomeric Robotic Mobility System. The system's parts include worm-inspired robotic limbs that an astronaut can easily snap onto a base, and that work together as a walking robot. Depending on the mission, parts can be configured to build, for instance, large "pack" bots capable of carrying heavy solar panels up a hill. The same parts could be reconfigured into six-legged spider bots that can be lowered into a lava tube to drill for frozen water.

"You could imagine a shed on the moon with shelves of worms," says team leader George Lordos, a PhD candidate and graduate instructor in MIT's Department of Aeronautics and Astronautics (AeroAstro), in reference to the independent, articulated robots that carry their own motors, sensors, computer, and battery. "Astronauts could go into the shed, pick the worms they need, along with the right shoes, body, sensors and tools, and they could snap everything together, then disassemble it to make a new one. The design is flexible, sustainable, and cost-effective."

Lordos' team has built and demonstrated a six-legged WORMS robot. Last week, they presented their results at IEEE's Aerospace Conference, where they also received the conference's Best Paper Award.

MIT team members include Michael J. Brown, Kir Latyshev, Aileen Liao, Sharmi Shah, Cesar Meza, Brooke Bensche, Cynthia Cao, Yang Chen, Alex S. Miller, Aditya Mehrotra, Jacob Rodriguez, Anna Mokkapati, Tomas Cantu, Katherina Sapozhnikov, Jessica Rutledge, David Trumper, Sangbae Kim, Olivier de Weck, Jeffrey Hoffman, along with Aleks Siemenn, Cormac O'Neill, Diego Rivero, Fiona Lin, Hanfei Cui, Isabella Golemme, John Zhang, Jolie Bercow, Prajwal Mahesh, Stephanie Howe, and Zeyad Al Awwad, as well as Chiara Rissola of Carnegie Mellon University and Wendell Chun of the University of Denver.

Animal instincts

WORMS was conceived in 2022 as an answer to NASA's Breakthrough, Innovative and Game-changing (BIG) Idea Challenge -- an annual competition for university students to design, develop, and demonstrate a game-changing idea. In 2022, NASA challenged students to develop robotic systems that can move across extreme terrain, without the use of wheels.

A team from MIT's Space Resources Workshop took up the challenge, aiming specifically for a lunar robot design that could navigate the extreme terrain of the moon's South Pole -- a landscape that is marked by thick, fluffy dust; steep, rocky slopes; and deep lava tubes. The environment also hosts "permanently shadowed" regions that could contain frozen water, which, if accessible, would be essential for sustaining astronauts.

As they mulled over ways to navigate the moon's polar terrain, the students took inspiration from animals. In their initial brainstorming, they noted certain animals could conceptually be suited to certain missions: A spider could drop down and explore a lava tube, a line of elephants could carry heavy equipment while supporting each other down a steep slope, and a goat, tethered to an ox, could help lead the larger animal up the side of a hill as it transports an array of solar panels.

"As we were thinking of these animal inspirations, we realized that one of the simplest animals, the worm, makes similar movements as an arm, or a leg, or a backbone, or a tail," says deputy team leader and AeroAstro graduate student Michael Brown. "And then the lightbulb went off: We could build all these animal-inspired robots using worm-like appendages.'"

Snap on, snap off

Lordos, who is of Greek descent, helped coin WORMS, and chose the letter "O" to stand for "oligomeric," which in Greek signifies "a few parts."

"Our idea was that, with just a few parts, combined in different ways, you could mix and match and get all these different robots," says AeroAstro undergraduate Brooke Bensche.

The system's main parts include the appendage, or worm, which can be attached to a body, or chassis, via a "universal interface block" that snaps the two parts together through a twist-and-lock mechanism. The parts can be disconnected with a small tool that releases the block's spring-loaded pins.

Appendages and bodies can also snap into accessories such as a "shoe," which the team engineered in the shape of a wok, and a LiDAR system that can map the surroundings to help a robot navigate.

"In future iterations we hope to add more snap-on sensors and tools, such as winches, balance sensors, and drills," says AeroAstro undergraduate Jacob Rodriguez.

The team developed software that can be tailored to coordinate multiple appendages. As a proof of concept, the team built a six-legged robot about the size of a go-cart. In the lab, they showed that once assembled, the robot's independent limbs worked to walk over level ground. The team also showed that they could quickly assemble and disassemble the robot in the field, on a desert site in California.

In its first generation, each WORMS appendage measures about 1 meter long and weighs about 20 pounds. In the moon's gravity, which is about one-sixth that of Earth's, each limb would weigh about 3 pounds, which an astronaut could easily handle to build or disassemble a robot in the field. The team has planned out the specs for a larger generation with longer and slightly heavier appendages. These bigger parts could be snapped together to build "pack" bots, capable of transporting heavy payloads.

"There are many buzz words that are used to describe effective systems for future space exploration: modular, reconfigurable, adaptable, flexible, cross-cutting, et cetera," says Kevin Kempton, an engineer at NASA's Langley Research Center, who served as a judge for the 2022 BIG Idea Challenge. "The MIT WORMS concept incorporates all these qualities and more."

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Lasers and chemistry reveal how ancient pottery was made -- and how an empire functioned

Peru’s first great empire, the Wari, stretched for more than a thousand miles over the Andes Mountains and along the coast from 600-1000 CE. The pottery they left behind gives archaeologists clues as to how the empire functioned. In a new study in the Journal of Archaeological Science: Reports, researchers showed that rather than using “official” Wari pottery imported from the capital, potters across the empire were creating their own ceramics, decorated to emulate the traditional Wari style. To figure it out, the scientists analyzed the pottery’s chemical make-up, with help from laser beams.

“In this study, we looked at the idea of cosmopolitanism, of incorporating different cultures and practices into a society,” says M. Elizabeth Grávalos, a postdoctoral researcher at the Field Museum in Chicago and the study’s lead author. “We’re trying to show that potters were influenced by the Wari, but this influence was blended with their own local cultural practices.”

Grávalos says this model of cosmopolitanism is a little like trying to replicate a recipe from another culture, but with a local spin. “If you live in the US and you’re making pad thai at home, you might not have access to all the ingredients that someone living in Thailand would have, so you substitute some things,” she says. “Wari ceramics are a little like that — people throughout the empire were interested in Wari material culture, but they weren’t necessarily getting it directly from the Wari heartland. More often than not, we see local people trying to make their own version of Wari pottery.”

Grávalos and her colleagues led archaeological digs throughout Peru, working with local communities to excavate the thousand-year-old remains of households, tombs, and administrative centers, in search of Wari lifeways. The researchers were then granted permission from Peru’s Ministry of Culture to bring samples of ceramics from their excavations to Chicago for analysis.

Clay from different regions has a different chemical makeup, so studying the ceramics’ chemical makeup could tell the researchers if the pots were produced in different places or if they were all imported from the Wari capital.

“We’d take a tiny piece of a pot and used a laser to cut an even tinier piece, basically extracting a piece of the ceramic’s clay paste,” says Grávalos. “Then helium gas carried it to the mass spectrometer, which measures the elements present in the  clay paste.” (The lab set-up didn’t have open laser beams and floating shards of pottery cutting across the room, though — the whole process takes place on a microscopic scale inside a big boxy machine.)

The analysis showed that the pots excavated from distinct regions of Peru have different chemical signatures, and were therefore made with distinct clays. That helps show how the Wari culture spread.

Some empires, like the ancient Romans, took a “top-down” approach to spreading their aesthetic, shipping pottery across the Mediterranean so that people throughout the empire were using the official Roman style. Local potters emulating the traditional Wari style in their own work seems to hint at a more “bottom-up” approach.

“Of course, local people in all empires have some degree of agency and creative control — the only empire that’s truly top-down is the Borg from Star Trek,” says Patrick Ryan Williams, Curator of Archaeological Science and Director of the Elemental Analysis Facility  at the Field Museum and the study’s senior author. “Even the Romans had local people doing things their own way. But what we’re finding in this study is the agency of local peoples and the importance of local economies. In some regions, we find that Wari colonists had their own production centers and were recreating Wari lifeways locally. In other areas, we see that local communities made Wari pottery in their own way. I think that’s what’s really important about this study.”

The researchers say that the patterns revealed by this pottery could help explain why the Wari empire was able to thrive for so long. “Local production, even in a cosmopolitan society with lots of far-flung connections, makes a society more resilient,” says Williams. “If you’re entirely dependent on someone far away sending you things you need, you’re extremely vulnerable.”

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New approach to harvesting aerial humidity with organic crystals

Researchers of the Smart Materials Lab (SML) and the Center for Smart Engineering Materials (CSEM) at NYU Abu Dhabi (NYUAD) have reported a novel method of harvesting water from naturally occurring sources such as fog and dew.

In the study, Research Scientist Patrick Commins and Post-doctoral Associate Marieh B. Al-Handawi observed for the first time the process of water spontaneously condensing from its vapor to liquid form and moving across the surface of a slowly subliming organic crystal. This was found to be caused by changes in the width of small channels that appear on the surface of the crystal over time, which guide the condensed water across the crystal's surface.

In the paper titled Autonomous and Directional Flow of Water and Transport of Particles across a Subliming Dynamic Crystal Surface published in the journal Nature Chemistry, researchers describe the process of condensation and movement of water that carries particles on the surface of crystals of hexachlorobenzene, a compound that is often used as a fungicide. Due to sublimation, the surface of this material has a rigid topography with defined parallel channels. Small solid particles such as dust or even metallic nanoparticles were observed to move autonomously along the channels. The motion of these particles was found to be caused by the condensed aerial water, which migrates through the channels due to the change in the cross-section and width of the channels over time.

Autonomous water flow has previously been achieved utilizing either surface chemical modifications or precisely fabricated microchannels, or on the surface of natural systems such as some plants or insects. The findings from this new study hold the potential to guide the creation of new technologies to utilize naturally occurring sources of water such as dew and fog, which are currently only used by some desert plants and animals for survival. The new research builds on the understanding of water collection mechanisms of such biological structures, while it presents a fundamentally different mechanism for water transportation.

"The motion of water on solid surfaces is one of the most fundamental phenomena found in nature," said Panče Naumov, a leader of the Smart Materials Lab and Director of the Center for Smart Engineering Materials, and the corresponding author of the study. "Through millennia-long evolutionary processes, surfaces of natural organisms have been optimized for efficient transport of water for a variety of life-supporting functions. Plants have been seen to do this by moving water against gravity. Our team has discovered a new way to move water across a dynamic solid surface, a fundamentally new underlying principle of water collection. This can provide an inspiration for emerging technologies that could potentially maximize the efficiency of experimental systems used for the collection of aerial humidity."

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Webb Telescope captures rarely seen prelude to supernova

The rare sight of a Wolf-Rayet star -- among the most luminous, most massive, and most briefly detectable stars known -- was one of the first observations made by NASA's James Webb Space Telescope in June 2022. Webb shows the star, WR 124, in unprecedented detail with its powerful infrared instruments. The star is 15,000 light-years away in the constellation Sagittarius.

Massive stars race through their lifecycles, and only some of them go through a brief Wolf-Rayet phase before going supernova, making Webb's detailed observations of this rare phase valuable to astronomers. Wolf-Rayet stars are in the process of casting off their outer layers, resulting in their characteristic halos of gas and dust. The star WR 124 is 30 times the mass of the Sun and has shed 10 Suns' worth of material -- so far. As the ejected gas moves away from the star and cools, cosmic dust forms and glows in the infrared light detectable by Webb.

The origin of cosmic dust that can survive a supernova blast and contribute to the universe's overall "dust budget" is of great interest to astronomers for multiple reasons. Dust is integral to the workings of the universe: It shelters forming stars, gathers together to help form planets, and serves as a platform for molecules to form and clump together -- including the building blocks of life on Earth. Despite the many essential roles that dust plays, there is still more dust in the universe than astronomers' current dust-formation theories can explain. The universe is operating with a dust budget surplus.

Webb opens up new possibilities for studying details in cosmic dust, which is best observed in infrared wavelengths of light. Webb's Near-Infrared Camera (NIRCam) balances the brightness of WR 124's stellar core and the knotty details in the fainter surrounding gas. The telescope's Mid-Infrared Instrument (MIRI) reveals the clumpy structure of the gas and dust nebula of the ejected material now surrounding the star. Before Webb, dust-loving astronomers simply did not have enough detailed information to explore questions of dust production in environments like WR 124, and whether the dust grains were large and bountiful enough to survive the supernova and become a significant contribution to the overall dust budget. Now those questions can be investigated with real data.

Stars like WR 124 also serve as an analog to help astronomers understand a crucial period in the early history of the universe. Similar dying stars first seeded the young universe with heavy elements forged in their cores -- elements that are now common in the current era, including on Earth.

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Neolithic ceramics reveal dairy processing from milk of multiple species

A new study has found evidence of cheesemaking, using milk from multiple animals in Late Neolithic Poland.

The research suggests that early farmers reduced the lactose content in milk by making it into cheese or other dairy products like yoghurt, and used dairy products from a number of different animals, such as cows, sheep or goats.

Lactose intolerance was a common condition in almost everyone in Europe during the Neolithic and until the Late Bronze Age when the genetic mutation became widespread, enabling adults to produce lactase, the enzyme which breaks down lactose in the body.

Researchers looked at the practice of dairy processing in the Late Neolithic, identifying high curd-content residues in pottery indicating cheesemaking, and revealing that multiple dairy species were utilised.

Dr Harry Robson, from the Department of Archaeology at the University of York, said: "These results contribute significantly to our understanding of the use of dairy products by some of the earliest farmers of Central Europe.

"Whilst previous research has shown that dairy products were widely available in some European regions during this period, here, for the first time, we have clear evidence for a diversified dairy herd, including cattle, sheep and goats, from the analysis of ceramics."

The scientists and archaeologists from the Universities of York, Cambridge, Toru? and Kraków used a multi-stranded proteomic and lipid-analysis approach to investigate ceramics and deposits on their surface, from the site of S?aw?cinek in central Poland.

The new development provides evidence that cheesemaking (and other curd-enriching dairy processing) can be directly detected by scrutinising the proportion of curd proteins, by comparing proteomic data. The results are also the first of their kind in Europe.

Despite widespread lactose intolerance in the period, there is evidence of dairy being consumed during the Neolithic, such as animal bones with kill patterns expected for dairy herds, dairy lipids in ceramic vessels, and dairy proteins in ancient dental calculus or plaque.

Lead author, Miranda Evans, PhD student at Cambridge's Department of Archaeology, said: "The proteomic results showed that the ancient residues closely resembled both the modern cheesemaking residues and cheese itself and not whole milk. This reveals that the people of S?aw?cinek practised cheesemaking or another form of curd-enriching dairy processing."

Evidence of multiple species used for cheesemaking was backed up by the presence of both cow and sheep or goat bones on the site."

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Extensive catalog of exploding stars

Celestial phenomena that change with time such as exploding stars, mysterious objects that suddenly brighten and variable stars are a new frontier in astronomical research, with telescopes that can rapidly survey the sky revealing thousands of these objects.

The largest data release of relatively nearby supernovae (colossal explosions of stars), containing three years of data from the University of Hawaiʻi Institute for Astronomy's (IfA) Pan-STARRS telescope atop Haleakalā on Maui, is publicly available via the Young Supernova Experiment (YSE). The project, which began in 2019, surveyed more than 1,500 square degrees of sky every three days, and discovered thousands of new cosmic explosions and other astrophysical transients, dozens of them just days or hours after exploding.

The newly-released data contains information on nearly 2,000 supernovae and other luminous variable objects with observations in multiple colors. It is also the first to extensively use the multi-color imaging to classify the supernovae and estimate their distances.

Astrophysicists use large imaging surveys -- systematic studies of large areas of the sky over time -- and different parts of the electromagnetic spectrum for many scientific goals. Some are used to study distant galaxies and how they evolve over cosmic time, or look at specific regions of the sky that are especially important, such as the Andromeda Galaxy.

"Pan-STARRS produces a steady stream of transient discoveries, observing large areas of the sky every clear night with two telescopes," said Mark Huber, a senior researcher at IfA. "With over a decade of observations, Pan-STARRS operates one of the best calibrated systems in astronomy, with a detailed reference image of the static sky visible from Haleakalā. This enables rapid discovery and follow-up of supernovae and other transient events, well suited for programs like YSE to build up the sample required for analysis and this significant data release."

YSE is designed to find energetic astrophysical "transient" sources such as supernovae, tidal disruption events and kilonovae (extremely energetic explosions). These transients evolve quickly, rising to their maximum brightness and then fading away after a few days or months.

Multi-institution collaboration

The images from Pan-STARRS are transferred to UH's Information Technology Center for initial processing and scientific calibration by the Pan-STARRS Image Processing Pipeline. Higher-level processing, detailed analysis and storage was then performed using computing systems at the National Center for Supercomputing Applications' (NCSA) Center for Astrophysical Surveys (CAPS), the University of California, Santa Cruz (UCSC), and the Dark Cosmology Centre (DARK) at the Niels Bohr Institute at the University of Copenhagen.

The survey and the tools used to analyze the data are critical precursors to the upcoming Vera C. Rubin Observatory Legacy Survey of Space and Time, a new 8.4-meter telescope being built in Chile. Rubin Observatory will survey the entire sky every three nights, discovering so many variable and exploding objects that it will be impossible to obtain detailed follow-up observations. The ability to classify these objects from the survey data alone will be vital to choosing the most interesting ones for astronomers to target with other telescopes.

Gautham Narayan, deputy director of CAPS, is leading the cosmological analysis for the data sample and former CAPS graduate fellow Patrick Aleo is lead author of the paper, "The Young Supernova Experiment Data Release 1 (YSE DR1): Light Curves and Photometric Classification of 1975 Supernovae."

"Much of the time-domain universe is uncharted. We still do not know the progenitor systems of many of the most common classes of transients, such as type Ia supernovae, while still using these sources to try and understand the expansion history of our universe," Narayan said. "We've also seen one electromagnetic counterpart to a binary neutron star merger. There are many kinds of transients that are theoretically predicted, but have never been seen at all."

Ken Chambers, Pan-STARRS director, added that "this collaboration with the Young Supernova Experiment makes exceptional use of Pan-STARRS' ability to routinely survey the sky for transient phenomena and moving objects. We have provided an unprecedented sample of young supernovae discovered before their peak luminosity that will be an important resource for supernova researchers and cosmologists for many years. Looking ahead, Pan-STARRS will remain a crucial resource in the Northern Hemisphere to complement the Rubin Observatory in the Southern Hemisphere."

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Bird flu associated with hundreds of seal deaths in New England in 2022

Researchers at Cummings School of Veterinary Medicine at Tufts University found that an outbreak of highly pathogenic avian influenza (HPAI) was associated with the deaths of more than 330 New England harbor and gray seals along the North Atlantic coast in June and July 2022, and the outbreak was connected to a wave of avian influenza in birds in the region.

The study was published on March 15 in the journal Emerging Infectious Disease.

HPAI is more commonly known as bird flu, and the H5N1 strain has been responsible for about 60 million poultry deaths in the U.S. since October 2020, with similar numbers in Europe. The virus was known to have spilled over from birds into mammals, such as mink, foxes, skunk, and bears, but those were mostly small, localized events. This study is among the first to directly connect HPAI to a larger scale mortality event in wild mammals.

The co-first authors on the paper -- virologist and senior scientist Wendy Puryear and post-doctoral researcher Kaitlin Sawatzki, who both work in the Runstadler Lab at Cummings School -- have been researching viruses in seals for years. They credit their findings in the new study to a unique and robust data set made possible by a collaboration with wildlife clinics and rehabilitation and response organizations in the region, in particular with Tufts Wildlife Clinic and director Maureen Murray, V03, associate clinical professor at Cummings School, and an author on the paper.

"We have a better resolution and greater depth of detail on this virus than before because we were able to sequence it and detect changes almost in real time," said Puryear. "And we have pairings of samples, sometimes literally from a bird and a seal on the same beach."

The clinic has been conducting avian influenza surveillance on birds and some mammals since January 2022, shortly after this strain of avian influenza took a trans-Atlantic journey from Europe into the U.S. Through this testing, the team found a wide range of flu viruses, including at least three strains that crossed the Atlantic, and they witnessed consistent waves of infection in birds.

At the same time, in collaboration with NOAA's Greater Atlantic Region Marine Mammal Stranding Network, they were able to screen nearly all seals that came through the network, whether or not the animal appeared sick. The stranding network is composed of experts from state and federal wildlife and fisheries agencies, non-profit rehabilitation and response facilities, aquariums, and academic institutions who respond to strandings.

"Because of the genetic data that we gathered, we were the first to see a strain of the virus that's unique to New England. The data set will allow us to more meaningfully address questions of which animals are passing the virus to which animals and how the virus is changing," said Sawatzki.

How HPAI Is Transmitted

In addition to poultry, H5N1 also has had a huge impact on wild birds, especially sea birds. Multiple locations around the globe have experienced large die-offs, such as recently in Peru, where the virus killed 60,000 pelicans, penguins, and gulls.

At the time of the seal mortality event in New England, the virus was hitting gulls particularly hard, the researchers found. There are lots of ways gulls and other birds may transmit the virus to seals, they said. Seals and sea birds are coastal animals living in the same areas that have environmental contact, if not direct contact, since they share the same water and shoreline. A seal may contract the virus if it comes in contact with a sick bird's excrement or water contaminated by that excrement, or if it preys upon an infected bird.

The accepted knowledge is that H5N1 is nearly 100% fatal for domestic and wild birds other than waterfowl, and the same is proving true when it comes to spillover in wild mammals. All the seals that tested positive for HPAI were deceased at the time of sampling or succumbed shortly after. None of the animals that tested positive recovered. However, it's possible some asymptomatic or recovered cases never came into the stranding networks.

In addition to the seal mortality event in New England, which was the first time H5N1 was detected in marine mammals in the wild, other locations have lost marine mammals to the virus. Peru announced about 3,500 sea lions died from the virus, Canada reported a seal mortality event along the St. Lawrence Estuary, and there was a similar event with seals in the Caspian Sea, according to news reports from Russia.

A hotly debated topic among scientists is whether there has been mammal-to-mammal transmission of HPAI between seals.

"It's not surprising that you might have transmission between the seals, because it has happened with low pathogenic avian influenza," said Puryear. "However, we can't say definitively whether or not there has been mammal-to-mammal transmission of HPAI."

"To get strong evidence of mammal-to-mammal transmission, you need two things: lots of infected animals and time," explained Sawatzki. "Time for the virus to mutate, and time for the mutated virus to be transmitted to another seal. As the virus acquires mutations, we can see shared mutations in the sequences that are specific only to mammals and that haven't been seen in a bird before. We had the numbers, but this outbreak didn't last long enough to provide evidence for seal-to-seal transmission."

The research team found evidence that the virus mutated in a small number of seals. But fortunately, they have not seen a case of bird flu in seals along the Atlantic coast since the end of last summer. However, stranding season is about to start for harbor seals and gray seals, so they are bracing themselves for what might happen.

Prevention and Risk to Humans

The risk to the public remains low, according to the Centers for Disease Control and Prevention. Since December 2021, less than 10 human cases of H5N1 have been reported globally, and those cases occurred in people with direct exposure to infected poultry. There are no documented cases of human transmission for this variant.

However, there is the possibility it could become a larger issue for human health. Avian influenza emerged in 1996, and since 2003, 868 cases of human infection with H5N1 have been reported worldwide, according to the World Health Organization. Of those, 457 were fatal, roughly a 50% fatality rate.

"And that's why people get nervous about it," Puryear said.

There is a single-dose vaccine available for poultry, but it's not currently administered on a large scale -- in part because of cost and logistics, and in part because there's some concern it may make future surveillance of the virus more difficult. There's not much that can be done in terms of responding to the virus for wildlife, particularly given the scale at which infection is occurring.

Biosecurity is important in limiting the ways in which the virus can spread between and within species, the researchers said. For example, wild birds should be kept separate from domestic birds, such as backyard chickens. In addition, thorough and timely surveillance of domestic animals and wildlife is key to understanding how the virus is evolving to prepare the best possible vaccines and treatments.

Read more at Science Daily

How fishermen benefit from reversing evolution of cod

Leipzig. Intense fishing and overexploitation have led to evolutionary changes in fish stocks like cod, reducing both their productivity and value on the market. These changes can be reversed by more sustainable and far-sighted fisheries management. The new study by researchers from the German Centre for Integrative Biodiversity Research (iDiv), Leipzig University and the Institute of Marine Research in Tromsø, which was published in Nature Sustainability, shows that reversal of evolutionary change would only slightly reduce the profit of fishing, but would help regain and conserve natural genetic diversity.

The impact of global fisheries on marine ecosystems is severe: fish stocks have declined and the degradation of marine habitats as well as the loss of biodiversity have been accelerated. Less visible, intense fishing has also affected the age and size structure of fish stocks and caused evolutionary change, often towards lower growth rates, smaller maturation sizes and earlier reproduction age. For example, cod in the North Sea, which has been heavily exploited in the past, matures at sizes just above 50 cm, compared to more than 70 cm expected in an unfished population.

Earlier reproduction can increase stock resilience in the short-term, but over time results in populations with smaller fish that have less offspring. "At the end of the day, this can reduce both the productivity of a stock and the value on the market," says first author Hanna Schenk from iDiv and Leipzig University. "Apart from this, we don't know much about potential consequences such as trophic cascades and other ecosystem changes that feed back onto the harvested species and may interfere with critical ecological functions."

Only long-term planning can reverse evolutionary decline

But evolution is not a one-way street. This is why the researchers from iDiv, Leipzig University and the Institute of Marine Research in Tromsø (Norway) wanted to find out what it takes to reverse evolutionary decline after decades of intensive exploitation, in particular with regard to planning horizons in fisheries management. For this, they developed a model that took various processes into account: Biological growth and reproduction as well as economic harvesting costs and consumer preferences. The researchers also analysed potential trade-offs between economic profit and conservation targets.

They found that evolutionary decline is profitable to reverse under century-long planning horizons. With more typical short-term planning, stock recovery in terms of biomass is achieved, but evolutionary decline continues, albeit at much lower rates. "Fisheries typically consider short planning horizons of a few years. This stands in contrast to long-term sustainability and biodiversity targets," says Hanna Schenk. The researchers found that more far-sighted planning horizons would help to rebuild the stock but evolutionary decline continues. According to Schenk, reversing this process takes much longer than the recovery of the stock biomass and is only achieved with century-long planning horizons.

Appropriate conservation targets only slightly reduce profit

The researchers also show that setting conservation targets for restoring not only fish stocks, but also their genetic composition would only slightly reduce profits. The cost and time of evolutionary reversal could be reduced further if fisheries can select fish depending on their genes, which may be possible to some extent by choosing the time and place of harvest. However, current conservation agendas do not include the restoration of genetic diversity, for example target 14 of the Sustainable Development Goals (SGDs), which calls for an end to overfishing.

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Preterm babies do not habituate to repeated pain

Preterm infants do not get used to repeated pain in the way that full-term infants, children and adults do habituate to pain, finds a study led by UCL (University College London) researchers.

The authors of the new Current Biology paper say that if preterm infants have not yet developed the mechanism that enables people to get used to moderate pain, medical procedures in their first few weeks of life could potentially impact their development.

Lead author Dr Lorenzo Fabrizi (UCL Neuroscience, Physiology & Pharmacology) said: "The way that we can get used to things can be seen as the simplest example of behavioural and brain plasticity, and it is a basic part of memory and learning. Pain habituation is important because it enables us to preserve physical, emotional, and cognitive resources by not overreacting to pain that is unavoidable or not life-threatening.

"Our findings suggest that the ability to get used to repeated pain might develop during the third trimester of pregnancy, so that babies born prematurely have not yet developed this ability that full-term babies have right from birth."

The study involved 20 infants at University College London Hospitals (UCLH). Half of them were preterm (and tested while still younger than 35 weeks gestational age*), while the other half were either born at full term (seven infants) or preterm but tested at term age (three infants). The two groups were comparable in terms of their actual postnatal age, as the preterm babies had a median age of 14 days, compared to 10 days among the full-term (or term age) group.

The researchers were measuring the infants' responses to a painful but clinically required heel lance (blood test), which was conducted twice (three to 18 minutes apart) for each infant (two lances are sometimes required to collect enough blood; this is not needed for most infants so only those that needed a second lance were included in the study).

Heel lances can elicit substantial pain responses in infants, but it was not previously known whether this decreases on repeated lances. To understand this, the researchers recorded the infants' brain activity with EEG (electroencephalography) electrodes placed on the scalp, and their heart rates using ECG (electrocardiography), while also monitoring their facial expressions and reflexes in withdrawing the leg.

The researchers found that the brain activity was not as strong immediately after the second heel lance, compared to the first, suggesting a habituation response, but this was only the case for full-term infants. They found a similar pattern for heart rate and facial expressions, as preterm infants reacted just as strongly to both heel lances, while the full-term infants appeared to habituate to the pain.

The team says this habituation response might be due to the full-term infants anticipating the imminent pain when they receive a second heel lance, so their reaction is less pronounced, or it may instead or additionally be due to their brains modulating their reflexive survival responses.

They add that habituation to pain might protect the full-term infants, but not those who were pre-term, from potential consequences to their development.

First author Dr Mohammed Rupawala (UCL Neuroscience, Physiology & Pharmacology) said: "While unpleasant and painful clinical procedures are necessary for many young infants, there is the potential to impact their development, such as by altered pain perception, or potentially reduced grey matter or disrupted white matter in the brain."

Co-author Dr Judith Meek, consultant neonatologist at UCLH, said: "This work raises awareness of the extra vulnerability of premature babies to pain. Clinicians need to do their best to protect them from repeated painful experiences. This should be regarded as an essential component of brain oriented newborn care."

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'Terminator zones' on distant planets could harbor life

In a new study, University of California, Irvine astronomers describe how extraterrestrial life has the potential to exist on distant exoplanets inside a special area called the "terminator zone," which is a ring on planets that have one side that always faces its star and one side that is always dark.

"These planets have a permanent day side and a permanent night side," said Ana Lobo, a postdoctoral researcher in the UCI Department of Physics & Astronomy who led the new work, which just published in The Astrophysical Journal. Lobo added that such planets are particularly common because they exist around stars that make up about 70 percent of the stars seen in the night sky -- so-called M-dwarf stars, which are relatively dimmer than our sun.

The terminator is the dividing line between the day and night sides of the planet. Terminator zones could exist in that "just right" temperature zone between too hot and too cold.

"You want a planet that's in the sweet spot of just the right temperature for having liquid water," said Lobo, because liquid water, as far as scientists know, is an essential ingredient for life.

On the dark sides of terminator planets, perpetual night would yield plummeting temperatures that could cause any water to be frozen in ice. The side of the planet always facing its star could be too hot for water to remain in the open for long.

"This is a planet where the dayside can be scorching hot, well beyond habitability, and the night side is going to be freezing, potentially covered in ice. You could have large glaciers on the night side," Lobo said.

Lobo, alongside Aomawa Shields, UCI associate professor of physics & astronomy, modeled the climate of terminator planets using software typically used to model our own planet's climate, but with a few adjustments, including slowing down planetary rotation.

It's believed to be the first time astronomers have been able to show that such planets can sustain habitable climates confined to this terminator region. Historically, researchers have mostly studied ocean-covered exoplanets in their search for candidates for habitability. But now that Lobo and her team have shown that terminator planets are also viable refuges for life, it increases the options life-hunting astronomers have to choose from.

"We are trying to draw attention to more water-limited planets, which despite not having widespread oceans, could have lakes or other smaller bodies of liquid water, and these climates could actually be very promising," Lobo said.

One key to the finding, Lobo added, was pinpointing exactly what kind of terminator zone planet can retain liquid water. If the planet is mostly covered in water, then the water facing the star, the team found, would likely evaporate and cover the entire planet in a thick layer of vapor.

But if there's land, this effect shouldn't occur.

"Ana has shown if there's a lot of land on the planet, the scenario we call 'terminator habitability' can exist a lot more easily," said Shields. "These new and exotic habitability states our team is uncovering are no longer the stuff of science fiction -- Ana has done the work to show that such states can be climatically stable."

Recognizing terminator zones as potential harbors for life also means that astronomers will need to adjust the way they study exoplanet climates for signs of life, because the biosignatures life creates may only be present in specific parts of the planet's atmosphere.

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