Vexillum vulpecula

<p>Understanding the evolution of insect speed, particularly across various species, is no simple task. For example, mosquitoes, apart from being known nuisances, have always fascinated scientists for their rapid wingbeats. Astonishingly, <a href="https://www.earth.com/news/mosquito-biting-season-extended-by-light-pollution/" target="_blank" rel="noreferrer noopener">mosquitoes</a> can flap their wings over 800 times per second.</p>



<p>How can such a tiny creature achieve such speed, especially when the pace at which its muscles flap outpaces the speed at which its nervous system commands them to beat? This odd asynchronous beating, a phenomenon that seemed alien to many, is a key to understanding an evolutionary marvel.</p>



<h2 class="wp-block-heading" id="h-asynchronous-flight-drives-insect-speed">Asynchronous flight drives insect speed</h2>



<p>The principle of asynchronous beating means that there's a detachment between the neural commands and muscle contractions. Interestingly, this is observed in only four distinct insect groups. </p>



<p>The assumption for years was that these groups evolved these unique wingbeats separately. However, a game-changing research collaboration between the <a href="https://www.gatech.edu/" target="_blank" rel="noreferrer noopener">Georgia Institute of Technology</a> and the <a href="https://ucsd.edu/" target="_blank" rel="noreferrer noopener">University of California, San Diego</a> (UC San Diego) suggests otherwise. These high-frequency wingbeats, they discovered, originated from a single common ancestor.</p>



<p>As Jeff Gau, one of the lead authors of the study and a Ph.D. graduate from Georgia Tech, highlighted, their findings delve deep into evolutionary history, tracing back to how ancient insect muscles functioned around 400 million years ago.</p>



<p>“Our findings are pretty robust to all different experimental conditions,” said Gau. “We’re looking back 400 million years into how ancient insect muscles must have behaved from an evolutionary standpoint.”</p>



<h2 class="wp-block-heading" id="h-some-insects-are-in-sync">Some insects are in sync</h2>



<p><a href="https://www.earth.com/news/moths-found-to-be-critically-important-pollinators/" target="_blank" rel="noreferrer noopener">Moths</a>, in contrast to mosquitoes, synchronize their flight muscles with every wing stroke. But, in an evolutionary twist, moths' ancestors possessed asynchronous flight capability but lost it over time. The catch? <a href="https://www.earth.com/news/male-moths-use-an-aphrodisiac-during-mating-to-feel-macho/" target="_blank" rel="noreferrer noopener">Moths</a> still have the capability for asynchronous muscle contractions.</p>



<p>To decode the evolutionary journey, scientists mapped flight strategies onto the two foundational ways physicists interpret oscillations. By integrating biophysical models with cutting-edge robotics, they showcased that these two strategies are essentially two facets of the same model. </p>



<p>A few evolutionary tweaks, and an insect can seamlessly transition between synchronous and asynchronous flight modes.</p>



<h2 class="wp-block-heading" id="h-how-size-impacts-insect-speed">How size impacts insect speed</h2>



<p>Size plays a crucial role. Many larger <a href="https://www.earth.com/news/global-insect-decline-what-are-the-causes-and-consequences/" target="_blank" rel="noreferrer noopener">insects</a> achieve synchronous flight, matching wing movement with nervous system pulses. But, for their smaller counterparts, this becomes a challenge. As they grow smaller, their wingbeats amplify, reaching speeds of up to 100 times per second. </p>



<p>According to Simon Sponberg, Dunn Family Early Career Associate Professor of Physics and Biological Sciences at Georgia Tech, there's a natural speed barrier. If these tiny insects attempt to contract and relax their wings at such a pace, the wings would overlap and ultimately malfunction.</p>



<p>“As insects became smaller, their wingbeats increased to 100 times per second, and when you start getting up to that speed, there's sort of an inherent speed limit where the muscle can't contract and relax fast enough,” said Sponberg. “If they tried to contract and relax the wings, they'd start overlapping and then eventually lock up.”</p>



<p>Instead, smaller insects evolved a unique mechanism. Their nervous system dispatches a pulse of activity, priming the muscles for contraction, regardless of the need for a wingbeat. This efficient method ensures that wings flap at a remarkable speed without awaiting neural activation and relaxation for each motion.</p>



<h2 class="wp-block-heading" id="h-new-understanding-of-insect-speed-evolution">New understanding of insect speed evolution</h2>



<p>Historically, scientists believed that asynchronous flight was an evolutionary trait that insects stumbled upon independently to increase their speed. But recently released phylogenies, evolutionary family trees of species, painted a different picture. </p>



<p>Asynchrony didn't emerge individually in separate evolutionary timelines. It sprouted once and then branched out. Over the ages, some <a href="https://www.earth.com/earthpedia-articles/are-insects-animals/" target="_blank" rel="noreferrer noopener">insect</a> groups thrived with their newfound speed and held onto it. At the same time, others reverted to synchronous flight.</p>



<p>Sponberg uses the analogy of oscillations to illustrate this concept. The principle of a dancing balloon at a car dealership, oscillating continuously, not by external force but due to a consistent air jet, mimics the way asynchronous flight functions in insects.</p>



<p>“If you've ever watched one of those dancing balloon guys at a car dealership, it goes up and collapses repeatedly,” Sponberg said. “What’s happening there is it's oscillating, not because you're poking it regularly, but you're actually providing a continuous air jet in the bottom, which is a trade-off with the force of gravity.”</p>



<h2 class="wp-block-heading" id="h-robots-mimicking-nature">Robots mimicking nature</h2>



<p>To deepen their understanding, the researchers at UC San Diego developed robots inspired by the moth's flight mechanism. Two distinct robots were created: a larger flapper robot operating in water and a smaller flapper robot, modeled after Harvard's <a href="https://wyss.harvard.edu/technology/robobees-autonomous-flying-microrobots/" target="_blank" rel="noreferrer noopener">Robobee</a>, functioning in the air. </p>



<p>These robots weren't mere scientific toys. They were crucial in proving that the models developed to explain flight transitions and insect speed held up in practical scenarios. </p>



<p>“You don’t need robotics to learn something about biology,” said Nick Gravish, an associate professor at UC San Diego. “But there’s something about building a bio-inspired robot that forces you to put yourself in the animal’s shoes.”</p>



<p>James Lynch, a Ph.D. graduate from UC San Diego and co-lead on the paper, emphasized the significance, noting that they had essentially built the first robot capable of mimicking evolutionary transitions in insect flight.</p>



<p>&nbsp;“The physics of this much larger robot moving much more slowly are similar to those of an insect that's a lot smaller and moving a lot faster,” said Lynch.</p>



<h2 class="wp-block-heading" id="h-interdisciplinary-brilliance">Interdisciplinary brilliance</h2>



<p>Such discoveries were only attainable through the confluence of varied disciplines, including physics, evolutionary biology, and robotics. This interdisciplinary approach, as <a href="https://www.setonhill.edu/academics/meet-the-faculty/detail/brett-aiello-phd/" target="_blank" rel="noreferrer noopener">Brett Aiello</a> from Seton Hill University noted, is pivotal in gaining profound insights into natural processes governing animal movement.</p>



<p>“One of the biggest evolutionary findings here is that these transitions are occurring in both directions and that instead of using multiple independent origins of asynchronous muscle, there's actually only one,” said&nbsp;Aiello. “From that one independent origin, multiple revisions back to synchrony have occurred.”</p>



<p>In essence, the study is a testament to the magic that happens when different fields unite with a shared purpose. Through this collective effort, we now have a clearer understanding of the wonders of insect flight and the evolutionary dance that has shaped it.</p>



<p>The full research paper was published in&nbsp;<em>Nature</em>, titled, “<a href="https://www.nature.com/articles/s41586-023-06606-3" target="_blank" rel="noreferrer noopener">Bridging two insect flight modes in evolution, physiology, and robophysics</a>.”</p>



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Amazing fact: Insect wings flap faster than their brain speed can command

Understanding the evolution of insect speed, particularly across various species,...

<p><a href="https://www.earth.com/news/cats-have-a-better-quality-of-life-if-you-play-with-them/">Cats</a> have captivated our attention for their wide range of vocalizations, from meows to screeches. However, it's their mysterious purring that has been a subject of fascination and study for many years.&nbsp;</p>



<p>Cats are not the only animals that purr, as once believed. Some wild cats, mongooses, hyenas, guinea pigs, and raccoons also purr.</p>



<p>Interestingly, purring and roaring are mutually exclusive. This means that cats that purr (such as mountain lions) can’t roar, while cats that roar (such as tigers) can’t purr.&nbsp;</p>



<h2 class="wp-block-heading" id="h-how-do-cats-purr">How do cats purr?</h2>



<p>A new study led by Austrian voice scientist Christian T. Herbst at the University of Vienna is challenging long-standing beliefs surrounding the mechanics of cat purring.&nbsp;</p>



<p>Contrary to previous understanding, the study reveals that the generation of cat purrs does not rely on cyclic muscle contractions - a perspective held by the scientific community for over fifty years.</p>



<p>"We propose that the ability to produce self-sustained oscillation at purring-like frequencies is facilitated by a special anatomical adaptation," wrote the researchers.</p>



<h2 class="wp-block-heading" id="h-cat-vocalizations">Cat vocalizations</h2>



<p>Cats produce various sounds, including meows and screeches. These sounds were not previously considered unique from a voice production standpoint as they originate in the cat's larynx, or "voice box." This mechanism is shared with humans and many other mammals.&nbsp;</p>



<h2 class="wp-block-heading" id="h-"></h2>



<p>However, cat purrs were believed to be different. They were thought to be produced through continuous cyclic contractions and relaxations of muscles in the vocal folds in the larynx, which would require consistent neural input and control from the brain.</p>



<h2 class="wp-block-heading" id="h-a-new-viewpoint-nbsp">A new viewpoint&nbsp;</h2>



<p>The study led by Herbst introduces a different viewpoint. According to the findings, cyclic muscle contractions are not imperative for the production of cat purrs.&nbsp;</p>



<p>Through controlled laboratory experiments, the researchers observed that the domestic cat larynx could yield low-pitched sounds characteristic of purring without the need for cyclical neural input or repetitive muscle contractions.</p>



<h2 class="wp-block-heading" id="h-unexpected-findings-nbsp">Unexpected findings&nbsp;</h2>



<p>These findings reveal an unexpected similarity between the sound production mechanism of cat purring and the human “creaky voice” or “vocal fry.”&nbsp;</p>



<p>The data shows that cats can produce purring sounds at extraordinarily low frequencies (20-30 Hz), which is surprising considering their small size and weight.</p>



<h2 class="wp-block-heading" id="h-unique-anatomical-adaptation-nbsp">Unique anatomical adaptation&nbsp;</h2>



<p>“Anatomical investigations revealed a unique ‘pad’ within the cats’ vocal folds that may explain how such a small animal, weighing only a few kilograms, can regularly produce sounds at those incredibly low frequencies (20-30 Hz, or cycles per second) – far below even than lowest bass sounds produced by human voices," said Herbst.</p>



<p>While the study does not entirely debunk the older theory, it shows that our current understanding of cat purring is incomplete and further investigation is needed.&nbsp;</p>



<p>The more we learn about the mechanisms and functions of purring, the better we can protect the well-being of our cats and accommodate their needs.</p>



<h2 class="wp-block-heading" id="h-more-about-purring-nbsp">More about purring&nbsp;</h2>



<p>Some researchers believe that purring helps cats heal. The low frequency of purrs causes a series of related vibrations within their body, which can:</p>



<ul>
<li>Heal bones and wounds.</li>



<li>Build muscle and repair tendons.</li>



<li>Ease breathing.</li>



<li>Reduce pain and swelling.</li>
</ul>



<p>Kittens start to pur when they are a few days old during nursing, which could be a way of communicating relaxation and contentment to their mothers. Adult cats also purr when they feel safe and comfortable.</p>



<p>Cats may also purr during stressful or painful moments, like while visiting a vet or during illness. This is believed to release endorphins, which can relieve pain.</p>



<p>The study is published in the journal <a href="http://dx.doi.org/10.1016/j.cub.2023.09.014" target="_blank" rel="noreferrer noopener"><em>Current Biology</em></a><em>.</em></p>



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Cat purring remains a mystery that we don't fully understand

Cats have captivated our attention for their wide range of...

The,Monk,Parakeet,(myiopsitta,Monachus),,Also,Known,As,The,Quaker

<p>If you have ever been mesmerized by a parrot's ability to mimic sounds or words, you are not alone. Their vocal flexibility, or "voice print," has always sparked curiosity, leading to questions about how these birds maintain their unique identity within the cacophony of flock calls.</p>



<p>However, recent findings by the <a href="https://www.ab.mpg.de/" target="_blank" rel="noreferrer noopener">Max Planck Institute of Animal Behavior</a> and Museu de Ciències Naturals de Barcelona might provide a clue. The secret, it appears, lies in a distinct voice print, akin to the one we humans have.</p>



<h2 class="wp-block-heading" id="h-a-parrot-s-voice-print">A parrot's voice print</h2>



<p><a href="https://www.earth.com/news/smart-parrots-need-more-stimulation-in-captivity/" target="_blank" rel="noreferrer noopener">Parrots</a> are renowned for their expansive vocal repertoire, which they can extend and modify throughout their lives. But with such dynamic vocal changes, how do they remain identifiable in a noisy flock? This conundrum led researchers to the monk parakeets of Barcelona.</p>



<p>Through an in-depth study, Simeon Smeele from the Max Planck Institute proposed that these birds might possess an individualized 'voice print' that stays consistent, irrespective of the sounds they produce.</p>



<p>Humans, despite their versatile vocal abilities, have always been identifiable through their unique voice tones. This voice print ensures that our vocal tract leaves a signature. Our voice makes us distinguishable even if we change what we're saying or how we're saying it.</p>



<p>It's known that many social animals, like dolphins and bats, have specific "signature calls" that make them recognizable within their groups. Yet, unlike the broad vocal range in humans, these signature calls are often limited to one type. This revelation presented a void in understanding: could other animals possibly have a voice print like humans?</p>



<h2 class="wp-block-heading" id="h-the-monk-parakeets-voice-print">The monk parakeets' voice print</h2>



<p>Simeon Smeele embarked on this research with a particular interest in parrots. This is mainly because they utilize their tongue and mouth to modulate calls. This modulation gives their sounds a more 'human' feel compared to other birds. The bustling parrot flocks in Barcelona, with their fluid membership, provided a perfect backdrop for this exploration.</p>



<p>With the assistance of <a href="https://museuciencies.cat/en/" target="_blank" rel="noreferrer noopener">Museu de Ciències Naturals de Barcelona</a>, which has identified over 3000 individual <a href="https://www.earth.com/news/monk-parakeets-lose-social-standing-if-they-take-long-vacations/" target="_blank" rel="noreferrer noopener">monk parakeets</a> over 20 years, Smeele and his team recorded calls from hundreds of these birds. Their extensive collection of over 5000 vocalizations made this the largest study of individually-marked wild parrots to date.</p>



<h2 class="wp-block-heading" id="h-analyzing-thousands-of-parrot-voice-prints">Analyzing thousands of parrot voice prints</h2>



<p>The team then analyzed these calls to detect individual recognition patterns. They were particularly intrigued by the “contact call”, a call previously believed to be stable and unique for each bird. However, their observations revealed otherwise, hinting that another mechanism might be at play for individual recognition.</p>



<p>Smeele turned to a machine learning model, commonly used in human voice recognition. By training the model on "tonal" calls from specific parrots and then testing it on a different "growling" call set, the team sought to determine the consistency of the voice print. The results were promising: the model identified individual <a href="https://www.earth.com/news/endangered-red-crowned-parrots-are-thriving-in-urban-texas-areas/" target="_blank" rel="noreferrer noopener">parrots</a> three times better than random chance.</p>



<h2 class="wp-block-heading" id="h-what-s-next">What’s next?</h2>



<p>While these findings hint at the existence of a voice print in monk parakeets, the team remains cautiously optimistic. Smeele emphasizes the need for more comprehensive data and further validation. Alongside this, an ecological study is also on the horizon. In the new study, <a href="https://www.earth.com/news/humans-have-relocated-caribbean-parrots-for-thousands-of-years/" target="_blank" rel="noreferrer noopener">parrots</a> will be tagged with GPS devices to understand their movements and interactions.</p>



<p>Juan Carlos Senar from the Museu de Ciències Naturals de Barcelona highlights the significance of these findings. Juan Carlos says that understanding the individual discrimination of calls can shed light on the species' unique vocal abilities.</p>



<p>If these parakeets indeed have a voice print, it not only answers the riddle of their vocal flexibility but could also reshape our understanding of animal communication. Smeele says the implications would go beyond parrots, too. “I hope that this finding prompts more work to uncover voice prints in other social animals that can flexibly modify their vocalization, such as dolphins and bats,” he says.</p>



<p>In a world filled with diverse sounds and calls, it's fascinating to think that each voice, be it human or bird, carries its unique signature, echoing its distinct identity.</p>



<p>The full study was published in the journal <a href="https://doi.org/10.1098/rsos.230835" target="_blank" rel="noreferrer noopener">Royal Society Open Science</a>.</p>



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Parrots have a unique voice print similar to humans

If you have ever been mesmerized by a parrot's ability...

<p>A new study published in the journal <a href="https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.3002269"><em>PLOS Biology</em></a> suggests that female animals may establish their mate preferences by noting the distinct traits selected by experienced females within their community.&nbsp;</p>



<p>The researchers, led by Emily DuVal at Florida State University, used a mathematical model to understand why females select certain mates.</p>



<h2 class="wp-block-heading" id="h-inferred-attractiveness-nbsp">Inferred attractiveness&nbsp;</h2>



<p>"Sexual selection by mate choice is a powerful force that can lead to evolutionary change, and models of why females choose particular mates are central to understanding its effects," wrote the study authors.</p>



<p>"Predominant mate choice theories assume preferences are determined solely by genetic inheritance, an assumption still lacking widespread support."</p>



<p>"Here, we propose a new model that explains this mate choice complexity with one general hypothesized mechanism, 'Inferred Attractiveness.'"&nbsp;</p>



<h2 class="wp-block-heading" id="h-observational-learning">Observational learning</h2>



<p>According to the model, younger females may observe the choices made by mature counterparts, eventually developing a preference for traits that are rare among males but are indicative of success.&nbsp;</p>



<p>The selected traits are not necessarily the focal points for the older females, but the younger observers may misconstrue them as desirable.&nbsp;</p>



<p>Through generations, as these distinctive traits become prevalent among males, they gradually lose their allure. This continuous shift in mate preferences helps sustain a diversity in male traits over time.</p>



<h2 class="wp-block-heading" id="h-sexual-selection-nbsp">Sexual selection&nbsp;</h2>



<p>The process of sexual selection, whereby traits gain popularity and become common due to their appeal, results in the emergence of unusual and often exaggerated characteristics in males, like extensive antlers, vibrant feathers, and extravagant courtship displays.&nbsp;</p>



<p>The precise reasons behind females favoring certain traits, however, remain elusive and complex. Preferences vary not only across different generations but also among individuals within the same generation.</p>



<h2 class="wp-block-heading" id="h-traditional-theories-nbsp">Traditional theories&nbsp;</h2>



<p>Traditional theories offer a few explanations. Some suggest that females might be inclined to seek out traits that signify superior genetic quality, while others propose that a positive feedback loop exists between male traits and female preferences.&nbsp;</p>



<p>Another perspective suggests that females’ sensory biases draw them towards specific traits.&nbsp;Despite these theories, none comprehensively explain the diverse range of traits and preferences observable in nature.</p>



<h2 class="wp-block-heading" id="h-female-preferences-nbsp">Female preferences&nbsp;</h2>



<p>The FSU study introduces an innovative viewpoint, proposing that females learn to discern attractive traits through observation. This observational learning plays a crucial role in the decision-making process.&nbsp;</p>



<p>Over time, the inferred attractiveness of specific traits influences the mate selection, resulting in the evolution and persistence of diverse male traits and female preferences within populations.</p>



<h2 class="wp-block-heading" id="h-study-implications-nbsp">Study implications&nbsp;</h2>



<p>This research not only sheds light on the intricate dynamics of mate selection but also on the rapid evolutionary changes and the enduring variation in traits and preferences seen in the animal kingdom.&nbsp;</p>



<p>The findings suggest that the process of mate selection is not merely about imitation but involves a complex interplay of observation, learning, and interpretation.</p>



<p>“While scientists have known for a long time that females can copy each other’s choice of mates, no one has previously considered that these copying females aren’t mind-readers," wrote the study authors.</p>



<p>"When we considered that females can make mistakes in identifying what traits others find attractive, we found this produces patterns that have long puzzled biologists, for example maintaining variety in male traits and female preferences over time.”</p>



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Female animals may acquire mate preferences through observation

A new study published in the journal PLOS Biology suggests...

<p>The impacts of 20th-century commercial whaling continue to linger today, according to research led by by Angela Sremba of Oregon State University (OSU). The study reveals a significant loss in <a href="https://www.earth.com/news/tree-species-diversity-makes-forests-more-productive/">genetic diversity</a> among surviving whales.&nbsp;</p>



<p>"The 20th century commercial whaling industry severely reduced populations of great whales throughout the Southern Hemisphere. The effect of this exploitation on genetic diversity and population structure remains largely undescribed," wrote the study authors.&nbsp;</p>



<p>"Over 2 million whales were killed by commercial whalers in the Southern Hemisphere during the 20th century. This included 345,775 Antarctic blue whales (Balaenoptera musculus intermedia), 215,848 humpback whales (Megaptera novaeangliae), and an astounding 726,461 fin whales."</p>



<h2 class="wp-block-heading" id="h-focus-of-the-study">Focus of the study</h2>



<p>The researchers set out to investigate genetic diversity changes among great whales in the South Atlantic. They examined DNA from whale bones found near abandoned whaling stations on South Georgia Island.</p>



<p>The bones, some of which are over a century old, were compared to DNA from contemporary whale populations. The study showed a pronounced loss of maternal DNA lineages among blue and humpback whales.&nbsp;</p>



<h2 class="wp-block-heading" id="h-loss-of-cultural-memories">Loss of cultural memories</h2>



<p>“A maternal lineage is often associated with an animal’s cultural memories such as feeding and breeding locations that are passed from one generation to the next. If a maternal lineage is lost, that knowledge is likely also lost," said Sremba.</p>



<p>South Georgia Island, situated approximately 800 miles southeast of the Falkland Islands, was an active hub for whaling from the early 1900s to the 1960s. The aftermath of this extensive hunting is still visible, with the island scattered with whale bones, preserved due to the region’s cold temperatures.</p>



<h2 class="wp-block-heading" id="h-rediscovering-their-habitat">Rediscovering their habitat</h2>



<p>Although commercial whaling has ceased, and South Atlantic whale populations are gradually recovering, the number of whale sightings near South Georgia is notably low. This indicates possible localized extinction, or extirpation, in the area's whale populations, according to study co-author Scott Baker, associate director of OSU’s Marine Mammal Institute.</p>



<p>“For 60 years, the whales have been absent from the South Georgia feeding grounds, suggesting that cultural memory was lost.” However, Baker noted that there are signs of whales gradually returning to the region, potentially “rediscovering” the habitat after the loss of cultural memory.</p>



<h2 class="wp-block-heading" id="h-dna-analysis">DNA analysis</h2>



<p>To assess the impact on genetic diversity, Sremba extracted and analyzed DNA from whale bones on South Georgia Island, comparing the findings to genetic data from current whale populations.&nbsp;</p>



<p>The analysis, encompassing humpback, blue, and fin whales, showed that while there is still high genetic diversity, there is evident loss of maternal DNA lineages in blue and humpback whales. The team couldn't discern diversity differences in fin whales due to the scarcity of post-whaling samples.</p>



<h2 class="wp-block-heading" id="h-maternal-lineages-nbsp">Maternal lineages&nbsp;</h2>



<p>Sremba, now affiliated with the Cooperative Institute for Marine Ecosystem and Resources Studies at OSU’s Hatfield Marine Science Center, emphasized that some whales alive today might have lived during the whaling era, given their lifespan can reach a century.&nbsp;</p>



<p>As these older whales pass away, further maternal lineages could be lost. Thus, preserving current genetic information is crucial.</p>



<h2 class="wp-block-heading" id="h-understanding-the-past">Understanding the past</h2>



<p>“It’s remarkable these species survived. In another 100 years, we don’t know what might change, and we can’t measure any change now if we don’t have a good understanding of the past," said Sremba.</p>



<p>The research offers valuable insights into the history and losses of whale populations due to whaling.</p>



<p>Baker noted that rising temperatures due to climate change could also lead to deterioration of the DNA in the bones on South Georgia Island. “This work is a way to preserve this history indefinitely."</p>



<p>The study is published in the <a href="http://dx.doi.org/10.1093/jhered/esad048" target="_blank" rel="noreferrer noopener"><em>Journal of Heredity</em></a><em>.</em></p>



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<p>.</p>

Echoes of the past: Whaling's long-term impact on genetic diversity

The impacts of 20th-century commercial whaling continue to linger today,...

<p>In 2018, underwater photographer Ryo Minemizu spotted an alien-like sea creature swimming off the coast of Okinawa. When the images were posted online, hundreds of exports struggled to identify the bizarre animal.&nbsp;</p>



<p>Minemizu collected a single sample of the animal and stored it in a formaldehyde solution at room temperature. Two years later, an international team of scientists performed morphological and genetic studies to identify the area creature, which was about the size of a ladybug.&nbsp;</p>



<p>The experts, led by neurobiologist Igor Adameyko of the University of Vienna, have finally solved the mystery. The team determined that the animal, Cercariae, was actually a colony of two types of parasitic worms swimming as one.</p>



<h2 class="wp-block-heading" id="h-cercariae-parasitic-flukes">Cercariae - Parasitic flukes</h2>



<p>"After microscopy-assisted exploration of the unstained specimen, we established that the aggregate is composed of two types of cercariae, which are henceforth referred to as the “sailors” (large ones) and the “passengers” (small ones)," wrote the study authors.&nbsp;</p>



<p>"The single aggregation we studied included about 20 sailors and over 1,000 passengers. Passenger cercariae were arranged in a hemisphere, with their tails forming the bulk and their bodies at the periphery. The tail tips of the sailor cercariae were anchored at the flattened side of the hemisphere, resembling snake hair on the Gorgon’s head."&nbsp;</p>



<p>"The passengers were much smaller volume-wise, as compared to large sailors. The aggregate resembles a colony, being finely structured and optimized for functional performance at different levels."</p>



<p>According to the researchers, the parasites had essentially created a prey-like swimmer that would infect the intestines of an unsuspecting host (see <a href="https://www.earth.com/wp-content/uploads/2023/10/strange-sea-creature_credit-Ryo-Minemizu_2medium.jpg">image</a>).</p>



<h2 class="wp-block-heading" id="h-moving-aggregation-nbsp">Moving aggregation&nbsp;</h2>



<p>"It is the sailor cercariae that provide the movement of the aggregation by wiggling their huge tails with wide lateral fin-folds," explained the experts.&nbsp;</p>



<p>"At the initiation of swimming, only one or few sailors start to wiggle tails, and the others join them soon after. Sailors have different collective activity regimes, as they can beat their tails in synchrony, causing pulsing or jumping movements of the aggregate, or asynchronously via alternating beating, which provides for a smooth motion without jumping patterns."</p>



<p>"The beating activity of sailors involves coordinated relaxation phases that occur in cercariae located exclusively at one specific side of the aggregate. When some of the sailor cercariae do not move, they are stretching behind, and their tails appear relaxed. Thus, the activity of sailors on one side and their inactivity on the opposite side can define the directionality of swimming."&nbsp;</p>



<p>"Altogether, the aggregate acts like a heteromorphic colony with integrated structure and coordinated behavior. We should note that studying a single specimen does not allow us to estimate the variations in locomotion patterns or in proportion between sailor and passenger cercariae."</p>



<h2 class="wp-block-heading" id="h-cercariae-have-astonishing-strategies">Cercariae have astonishing strategies </h2>



<p>The researchers pointed out that parasites have evolved a variety of astonishing strategies to survive within their hosts. </p>



<p>They noted that the discovery described in this study provides a unique example of how morphologically and functionally heterogeneous individuals of the same species cooperate to build colonial organisms for the purpose of infection.</p>



<p>The research is published in the journal <a href="https://www.cell.com/current-biology/fulltext/S0960-9822(23)01170-3" target="_blank" rel="noreferrer noopener"><em>Current Biology</em></a>.</p>



<p>Image Credit: Ryo Minemizu</p>



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Bizarre sea creature, Cercariae, is actually a colony of hundreds of parasitic worms

In 2018, underwater photographer Ryo Minemizu spotted an alien-like sea...

German,Shepherd,Smiling,And,Looking,Happy,Standing,On,Top,Of

<p>Gut microbes from wild wolves might be the solution for a severe gastrointestinal problem prevalent among domestic dogs. This new research from <a href="https://osucascades.edu/" target="_blank" rel="noreferrer noopener">Oregon State University – Cascades</a> is a significant stride towards resolving canine inflammatory bowel disease (IBD).</p>



<p>Canine IBD is a chronic disorder marked by symptoms like vomiting, diminished appetite, weight reduction, flatulence, stomach rumbling, and abdominal pain.</p>



<h2 class="wp-block-heading" id="h-no-cure-for-canine-ibd">No cure for canine IBD</h2>



<p>Bruce Seal, from OSU-Cascades’ biology program, shed light on the gravity of this issue, stating, “At present there is no known cure for this ongoing dysbiosis of the gastrointestinal tract, and there are limited options for treatment.” </p>



<p>The root causes span from an animal's genetics and environmental factors to the immunological state of the GI tract and notably, an altered gut microbiome.</p>



<p>This study is the result of a partnership between scientists at OSU-Cascades and Oregon State’s Carlson College of Veterinary Medicine. It signifies a move towards a food supplement or additive that can guide a domestic dog's gut microbiome back to its ancestral state, resembling that of a <a href="https://www.earth.com/news/dogs-and-wolves-have-social-learning-ability-and-can-remember-where-people-hid-food/" target="_blank" rel="noreferrer noopener">wolf</a>.</p>



<p>“The modern dog diet, high in carbohydrates, does not mirror a wolf’s diet. For instance, starches in processed dog food are indigestible, adversely affecting the microbial community in a dog's GI tract and consequently its gastric physiology,” Seal emphasized, shedding light on the drastic shift from the dietary habits of their wild ancestors.</p>



<h2 class="wp-block-heading" id="h-what-the-research-team-learned">What the research team learned</h2>



<p>The crucial data for this research came from the gastrointestinal content of a deceased <a href="https://www.earth.com/news/eastern-wolves-and-grey-wolves-evolved-separately/" target="_blank" rel="noreferrer noopener">wolf</a>, which had tragically died from car-inflicted injuries. This specimen allowed the scientists to isolate 20 unique gut bacteria. </p>



<p>Preliminary genetic examinations hinted at their probiotic properties. The study zoomed in on a newfound <a href="https://microbialcellfactories.biomedcentral.com/articles/10.1186/s12934-016-0603-7" target="_blank" rel="noreferrer noopener">Paenibacillus</a> strain, completing its whole genome sequencing.</p>



<p>Seal elaborated on the significance of this bacterium: “It encodes enzymes adept at digesting complex carbs such as starches. Moreover, it possesses gene systems that express antimicrobials.” </p>



<p>These non-toxic, spore-forming bacteria have the potential to foster anti-inflammatory responses in the gut and restrict pathogen growth. Seal concluded, “Considering all these factors, this bacterial isolate might emerge as an invaluable probiotic for our domesticated canine companions.”</p>



<p>In a promising direction, Seal divulged that the team is gearing up to undertake whole genome sequencing for another four or five bacterial species among the isolated 20.</p>



<p>The full study from the was published in journal <a href="https://www.mdpi.com/journal/applmicrobiol">Applied Microbiology</a>.</p>



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Wolves have gut bacteria that can help dogs with canine IBD

Gut microbes from wild wolves might be the solution for...

Vexillum vulpecula

Taxonomic tree: