Hallaxa translucens

<p>The long-held belief that jellyfish are simple creatures with limited cognitive abilities has been dramatically overturned.&nbsp;</p>



<p>A new study from the <a href="https://www.ku.dk/english/" target="_blank" rel="noreferrer noopener">University of Copenhagen</a> reveals that Caribbean box jellyfish are far more advanced than previously thought, displaying complex learning abilities despite their rudimentary nervous systems.</p>



<h2 class="wp-block-heading" id="h-not-so-simple-nbsp">Not so simple&nbsp;</h2>



<p>While jellyfish have inhabited our planet for over 500 million years, their reputation has mostly been that of uncomplicated beings.&nbsp;</p>



<p>This notion has been largely based on their primitive nervous systems, particularly when compared to organisms with advanced centralized <a href="https://www.earth.com/news/nutrition-for-neurons-the-role-of-breast-milk-in-shaping-our-brains/">brains</a>. The research, however, challenges this perspective.</p>



<p>"It was once presumed that jellyfish can only manage the simplest forms of learning, including habituation – i.e., the ability to get used to a certain stimulation, such as a constant sound or constant touch," said study co-author Professor Anders Garm.</p>



<p>"Now, we see that jellyfish have a much more refined ability to learn, and that they can actually learn from their mistakes. And in doing so, modify their behavior."</p>



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



<p>The focus of this research was the Caribbean box jellyfish, Tripedalia cystophora. Despite having only about a thousand nerve cells, these jellyfish displayed sophisticated learning mechanisms that allowed them to adapt their behavior based on experiences. Remarkably, they achieve this advanced learning at a rate similar to that of fruit flies and mice.</p>



<p>The team's experiments highlighted how these jellyfish use visual contrasts to gauge their distance from mangrove roots, enabling them to avoid potential harm.&nbsp;</p>



<p>What's even more fascinating is their ability to adjust their behavior based on changes in contrast conditions due to various environmental factors.</p>



<h2 class="wp-block-heading" id="h-associative-learning-nbsp">Associative learning&nbsp;</h2>



<p>"Our experiments show that contrast, i.e., how dark the root is in relation to the water, is used by the jellyfish to assess distances to roots, which allows them to swim away at just the right moment. Even more interesting is that the relationship between distance and contrast changes on a daily basis due to rainwater, algae and wave action," said Professor Garm.</p>



<p>"We can see that as each new day of hunting begins, box jellyfish learn from the current contrasts by combining visual impressions and sensations during evasive maneuvers that fail."</p>



<p>"So, despite having a mere one thousand nerve cells – our brains have roughly 100 billion – they can connect temporal convergences of various impressions and learn a connection – or what we call associative learning. And they actually learn about as quickly as advanced animals like fruit flies and mice."</p>



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



<p>This research is redefining our understanding of the capabilities of simple nervous systems. It presents the intriguing idea that advanced learning might have been a fundamental evolutionary advantage from the very inception of nervous systems.</p>



<p>"For fundamental neuroscience, this is pretty big news. It provides a new perspective on what can be done with a simple nervous system. This suggests that advanced learning may have been one of the most important evolutionary benefits of the nervous system from the very beginning," said Garm.</p>



<p>Further studies are now focusing on identifying the specific nerve cells responsible for this learning in jellyfish.&nbsp;</p>



<p>This knowledge could ultimately lead to a broader understanding about memory processes across different species and might even contribute to our comprehension of complex conditions like dementia.</p>



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



<p>The research team has also shown where the learning is happening in these box jellyfish. This has given them the unique opportunity to study the precise changes that occur in a nerve cell when it is involved in advanced learning.&nbsp;&nbsp;&nbsp;</p>



<p>"We hope that this can become a supermodel system for looking at cellular processes in the advanced learning of all sorts of animals," said Professor Garm.</p>



<p>"We are now in the process of trying to pinpoint exactly which cells are involved in learning and memory formation. Upon doing so, we will be able to go in and look at what structural and physiological changes occur in the cells as learning takes place."</p>



<h2 class="wp-block-heading" id="h-learning-how-memory-works-nbsp">Learning how memory works&nbsp;</h2>



<p>Professor Garm said that the team will eventually look for the same mechanisms in other animals, to see if this is how memory works in general.&nbsp;</p>



<p>"Understanding something as enigmatic and immensely complex as the brain is in itself an absolutely amazing thing. But there are unimaginably many useful possibilities."&nbsp;</p>



<p>"One major problem in the future will undoubtedly be various forms of dementia. I don’t claim that we are finding the cure for dementia, but if we can gain a better understanding of what memory is, which is a central problem in dementia, we may be able to lay a building block to better understand the disease and perhaps counteract it."</p>



<p>The study is published in the journal <a href="http://dx.doi.org/10.1016/j.cub.2023.08.056" target="_blank" rel="noreferrer noopener"><em>Current Biology</em></a><em>.</em></p>



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Jellyfish can learn from past experiences - even without a central brain

The long-held belief that jellyfish are simple creatures with limited...

<p>Scientists have recently discovered the massive fossil of a trapdoor spider in Australia, providing significant insights into the ancient arachnids’ history and <a href="https://www.earth.com/news/sustainable-practices-could-greatly-reduce-species-extinction-risk/">extinction</a> patterns in the region.</p>



<p>The fossil was unearthed at a site in the Central Tablelands in New South Wales. It represents the second-largest spider fossil ever found.&nbsp;</p>



<p>The astonishingly large spider, which has been named Megamonodontium mccluskyi, was more than five times the size of its modern relatives.&nbsp;</p>



<h2 class="wp-block-heading" id="h-dismal-fossil-record">Dismal fossil record</h2>



<p>The researchers explained that it has been challenging to piece together the intricate history of Australian spiders.&nbsp;</p>



<p>"Mygalomorph spiders have been present on the Australian landmass since before the break-up of Gondwana. Today, mygalomorphs are represented on the continent by a diverse fauna of 12 families," wrote the study authors.&nbsp;</p>



<p>"Despite this extensive evolutionary history, only one fossil mygalomorph spider has been found in Australia: Edwa maryae from the Triassic of Queensland."</p>



<p>"Presumably, this dismal fossil record is the result of a combination of the fragility of the animals and the tendency of females to stay within burrows, both of which prevent many spiders from entering the fossil record."&nbsp;</p>



<p>"The lack of fossils from Australia has made it difficult to decipher the evolutionary history of the group."</p>



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



<p>Matthew McCurry, a palaeontologist at UNSW, noted that only four spider fossils have previously been discovered in Australia.</p>



<p>“This discovery is so significant, it reveals new information about the extinction of spiders and fills a gap in our understanding," said McCurry. “The closest living relative of this fossil now lives in wet forests in Singapore through to Papua New Guinea."</p>



<p>“This suggests that the group once occupied similar environments in mainland Australia but have gone extinct as Australia became more arid.”</p>



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



<p>Notably, Megamonodontium mccluskyi shares a resemblance with the present-day brush-footed trapdoor spiders found in western New South Wales. It marks an essential milestone for researchers studying the ancient biodiversity and ecological shifts in Australia. The newfound fossil is believed to be between 11 to 16 million years old.</p>



<p>The fossilized spider draws its name from Dr. Simon McClusky, the scientist credited with its discovery. This monumental finding is the result of the collaborative efforts of scientists from ANU, UC, and UNSW.</p>



<h2 class="wp-block-heading" id="h-brush-footed-trapdoor-spiders">Brush-footed trapdoor spiders</h2>



<p>"Brush-footed trapdoor spiders (Araneae: Barychelidae) are a diverse clade of mygalomorph spiders that have evolved several features, including tufts of setae that allow them to climb smooth surfaces," wrote the study authors.&nbsp;</p>



<p>"Furthermore, their spinnerets are fairly short, which distinguishes them readily from the larger sympatric tarantulas (Theraphosidae). Australia is currently home to 10 genera of brush-footed trapdoor spiders, a center of biodiversity, if not also their origin."</p>



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



<p>Robert Raven, a Queensland Museum arachnologist and the supervising author of the research, offered further context on the discovery’s global significance.&nbsp;</p>



<p>"Not only is it the largest fossilized spider to be found in Australia but it is the first fossil of the family Barychelidae that has been found worldwide," said Raven.&nbsp;</p>



<p>"There are around 300 species of brush-footed trapdoor spiders alive today, but they don't seem to become fossils very often. This could be because they spend so much time inside burrows and so aren't in the right environment to be fossilized."</p>



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



<p>The spider fossil is now part of the Australian Museum’s palaeontology collection and is accessible online for research purposes, further facilitating the study of ancient arachnids. </p>



<p>Interestingly, the discovery site, known as McGraths Flat near Gulgong, has also been identified as the location where a new fossilized jumping spider was recently found.</p>



<p>The research is published in the <a href="https://academic.oup.com/zoolinnean/advance-article/doi/10.1093/zoolinnean/zlad100/7274985"><em>Zoological Journal of the Linnean Society</em></a>.</p>



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Prehistoric trapdoor spider was five times bigger than its modern relatives

Scientists have recently discovered the massive fossil of a trapdoor...

<p>Protecting your dog's teeth is very important. Periodontal disease is a prevalent issue among canines, impacting at least 80 percent of <a href="https://www.earth.com/news/typical-american-dog-knows-18-words-and-love-is-at-the-top-of-the-list/">dogs</a> over the age of three. The disease begins with gingivitis, characterized by red, inflamed gums that may bleed. </p>



<p>If untreated, the condition escalates to periodontitis, leading to progressive alveolar bone damage and potential tooth loss, while also increasing the risk of cardiovascular and lung diseases.</p>



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



<p>With poor oral hygiene identified as a principal cause of periodontal disease, leading to plaque and tartar build-up, regular teeth brushing for dogs is advised by veterinarians.&nbsp;</p>



<p>However, many people do not comply with this advice, often because their dogs will not cooperate.</p>



<h2 class="wp-block-heading" id="h-reducing-plaque-and-tartar">Reducing plaque and tartar</h2>



<p>Dr. Jerzy Gawor is a veterinary dentistry practitioner and researcher at the Arka Veterinary Clinic in Krakow, Poland, and lead author of a new study published in the journal <a href="http://dx.doi.org/10.3389/fvets.2023.1241197" target="_blank" rel="noreferrer noopener"><em>Frontiers in Veterinary Science</em></a>.&nbsp;</p>



<p>“Here we show that an additive to drinking water, based on pomegranate extract, can reduce the accumulation of plaque and tartar in dogs,” said Dr. Gawor. “This additive thus helps dogs to maintain healthy gums, and may ultimately help to limit the occurrence of periodontal disease.”</p>



<p>The researchers examined Vet Aquadent® FR3SH™ - an over-the-counter oral hygiene product developed by French veterinary company Virbac.&nbsp;</p>



<p>“We did this study after obtaining evidence that the main ingredient, pomegranate extract, limits the growth of oral bacteria in dogs in vitro, including species involved in periodontal disease," said study co-author Dr. Celine Nicolas, an employee of Virbac.</p>



<p>"There was also evidence that the other components, inulin and erythritol, likewise play a role in the maintenance of a healthy oral microbiome in dogs."</p>



<h2 class="wp-block-heading" id="h-studying-dogs-teeth">Studying dogs' teeth</h2>



<p>The product, which can be easily added to dogs’ drinking water, was tested on 40 dogs representing 14 breeds. All subjects had mild to moderate gingivitis but were otherwise healthy.</p>



<p>The dogs were monitored over 30 days after a professional dental cleaning session. The research involved thorough oral health assessments, dental charting, and mouth radiography under general anesthesia.</p>



<p>Dogs were then divided into two groups: one receiving water with a 1% solution of Vet Aquadent® FR3SH™ daily, and the other receiving plain water. During the study, no other oral hygiene practices were implemented.</p>



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



<p>After 30 days, dogs receiving the pomegranate extract additive had a 47 percent reduction in plaque and a 24 percent decrease in tartar. Furthermore, the gums of dogs in the treatment group were completely healthy.&nbsp;</p>



<p>“The results showed that 30 days after the dental cleaning and polishing, dogs which had received the additive daily scored 47% lower for the amount of plaque, and had a 24% lower score for the amount of tartar, compared to dogs in the control group. The gum was also completely healthy in the active treatment group,” wrote the study authors.&nbsp;</p>



<h2 class="wp-block-heading" id="h-healthier-dog-teeth">Healthier dog teeth</h2>



<p>The study thus affirmed that the additive effectively limits plaque and tartar reformation post professional dental cleaning.&nbsp;</p>



<p>Dr. Gawor and team suggest that the product works by restricting the growth of harmful bacteria, especially preventing bacterial biofilms formation.</p>



<p>"Daily oral hygiene and prophylaxis are essential to prevent periodontal diseases in dogs. This includes active methods like brushing, passive methods like dental chews or water additives, or a combination, as well as regular clinical dental checks," said Dr. Gawor.</p>



<p>"The frequency of the latter should depend on the dog’s age, breed, size, and predisposition, as determined by veterinary clinicians."</p>



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Protect your dogs' teeth by using mouthwash with pomegranate

Protecting your dog's teeth is very important. Periodontal disease is...

<p>During a recent deep-sea dive off the coast of Hawaii, scientists encountered a rare and mesmerizing ocean creature known as the “Dumbo octopus."&nbsp;</p>



<p>This remarkable sighting occurred approximately a mile below the ocean's surface, on an unnamed seamount located within the <a href="https://www.papahanaumokuakea.gov/" target="_blank" rel="noreferrer noopener">Papahānaumokuākea</a> Marine National Monument.</p>



<p>The expedition was funded by the <a href="https://nautiluslive.org/video/2023/09/27/cute-dumbo-octopus-eyes-rov-hercules">National Oceanic and Atmospheric Association</a> (NOAA).&nbsp;</p>



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



<p>The Dumbo octopus, also known as Grimpoteuthis, belongs to the umbrella <a href="https://www.earth.com/news/octopus-and-squid-senses-linked-to-human-brain-evolution/">octopus</a> family. The nickname "Dumbo" comes from its resemblance to the character in Disney's 1941 film, due to the prominent ear-like fins situated on top of its head. The octopus utilizes these fins to gracefully propel itself through the water, as it searches for food.</p>



<p>The Dumbo <a href="https://www.earth.com/news/secret-garden-thermal-springs-accelerate-octopus-egg-hatching-by-years/" target="_blank" rel="noreferrer noopener">octopus</a> is usually found in the deep waters of the central Pacific at depths ranging from 1,300 to 13,000 feet. However, some of these intriguing animals have been found as deep as 23,000 feet.&nbsp;</p>



<p>Because they live in such deep, dark environments, their coloration can vary, often appearing in shades of red, pink, brown, or white.</p>



<h2 class="wp-block-heading" id="h-fascinating-footage-nbsp">Fascinating footage&nbsp;</h2>



<p>The footage of the Dumbo octopus was captured by the Exploration Vessel (E/V) Nautilus, providing a unique opportunity to observe the creature as it effortlessly drifts in the ocean's depths.&nbsp;</p>



<div class="wp-block-sendtonews-playerselector">[sendtonews key="9KGzHmAd5J-3029266-12187" type="single"]</div>



<p>The crew aboard the E/V Nautilus was fortunate enough to witness not just one, but five of these creatures in a single night.</p>



<h2 class="wp-block-heading" id="h-a-beautiful-experience">A beautiful experience</h2>



<p>Jaina Galves, a video engineer intern who played a role in this discovery, shared her excitement about the experience.</p>



<p>“Each time, you’re kind of just roaming around with the ROV,” said Galves. “Somebody’s like, wait, what is that in the corner, and then everybody starts to gasp, everybody starts to freak out. And everybody’s like Dumbo octopus!"</p>



<p>"So we take the ROV over, we go, and we follow them. They move very slowly and very gracefully, so we get to follow them for quite a while.”</p>



<p>“It depends on what we’re doing and how long we can hang out. But for one of them, we just got to stay for quite a while. Just watched it kind of glide through the water, and it was beautiful.”</p>



<p>Galves told ABC News: “When I saw it on the screen, I couldn’t even say anything. My jaw was just on the floor.”</p>



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



<h3 class="wp-block-heading" id="h-size">Size</h3>



<p>Overall, scientists have discovered more than a dozen species of dumbo octopuses. The largest individual captured on film was nearly six feet long, according to the environmental group Oceana, but most are much smaller, with an average length of 8 to 12 inches.&nbsp;</p>



<h3 class="wp-block-heading" id="h-appearance">Appearance</h3>



<p>Dumbo octopuses are characterized by their unique umbrella-shaped appearance when their arms are spread. They possess a soft, gelatinous body, which is an adaptation to the deep-sea environment.</p>



<h3 class="wp-block-heading" id="h-diet">Diet</h3>



<p>The <a href="https://www.earth.com/earthpedia-articles/are-octopuses-smart/" target="_blank" rel="noreferrer noopener">octopuses</a> feed on crustaceans, benthic worms, and other small organisms found on the ocean floor. They often swallow their prey whole.</p>



<h3 class="wp-block-heading" id="h-reproduction-nbsp">Reproduction&nbsp;</h3>



<p>Unlike many other octopus species, Dumbo <a href="https://www.earth.com/news/do-octopuses-dream-a-recent-study-shows-octopuses-sleep-is-very-similar-to-humans/" target="_blank" rel="noreferrer noopener">octopuses</a> do not have a defined breeding season. They can lay eggs at any time, and the young are developed enough to survive on their own immediately after hatching. While their exact lifespan is unknown, it is believed to be about 3 to 5 years.</p>



<p>The species is known for its gentle and passive demeanor, and since it inhabits regions difficult for humans to access, it has not been extensively studied, and much about it remains a mystery.</p>



<p>The E/V Nautilus, owned by the nonprofit organization <a href="https://nautiluslive.org/" target="_blank" rel="noreferrer noopener">Ocean Exploration Trust</a>, is currently exploring the expansive Papahānaumokuākea Marine National Monument. This protected marine area spans over 500,000 square miles in the Pacific, making it larger than all U.S. national parks combined.</p>



<p>---</p>



<p>Video and image credit: NOAA Ocean Exploration via the Ocean Exploration Cooperative Institute</p>



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<p>.</p>

Ghostly "Dumbo octopus" captured on film and video in Hawaii

During a recent deep-sea dive off the coast of Hawaii,...

<p><a href="https://www.earth.com/news/humpback-whales-travel-thousands-of-miles-to-mate/">Humpback whales</a> have been engaging in a unique behavior involving seaweed. Experts believe that whales are not just using seaweed for play, but also for its antibacterial properties.</p>



<p>This intriguing behavior is documented in a paper by Dr. Olaf Meynecke of Griffith University. The research is published in the <a href="http://dx.doi.org/10.3390/jmse11091802"><em>Journal of Marine Science and Engineering</em></a><em>.</em></p>



<h2 class="wp-block-heading" id="h-sand-scrubs-nbsp">Sand scrubs&nbsp;</h2>



<p>In previous work, Dr. Meynecke described whales rolling in sandy substrates off the Gold Coast during their migration, presumably to shed dead skin cells and parasites.&nbsp;</p>



<h2 class="wp-block-heading" id="h-kelping-nbsp">Kelping&nbsp;</h2>



<p>The new paper delves into another understudied behavior displayed by baleen whales, including humpbacks, across various populations in the northern and southern hemispheres. The whales have been seen frolicking and rolling around with clumps of kelp and seaweed at the water’s surface.</p>



<p>According to Dr. Meynecke, the behavior was similar in different individuals, regardless of where in the world it occurred.&nbsp;&nbsp;</p>



<h2 class="wp-block-heading" id="h-focus-of-the-research-nbsp">Focus of the research&nbsp;</h2>



<p>For the investigation, three instances of "kelping" behavior on Australia's east coast were scrutinized through aerial observations, alongside 100 other documented seaweed interactions worldwide.&nbsp;</p>



<p>These interactions involved 163 baleen whales with the majority being humpbacks (in 95 separate events), followed by gray whales, southern right whales, and northern right whales.&nbsp;</p>



<h2 class="wp-block-heading" id="h-complex-behaviors-nbsp">Complex behaviors&nbsp;</h2>



<p>“The use of objects by cetaceans like baleen whales is well known, and their ability to interact with their environment in complex behaviors has been previously reported on,” said Dr. Meynecke. “But baleen whales, including humpback whales, are less often observed to perform object use, and this behavior might be more common than previously thought."&nbsp;</p>



<p>“There are two plausible theories: play and/or self-medication with seaweed. This behavior may be playful but could also serve additional benefits in the context of learning and socialising, as well as ectoparasite removal and skin treatment by using brown algae’s antibacterial properties.”&nbsp;</p>



<p>Dr. Meynecke emphasizes that recognizing this behavior across various whale populations is crucial for understanding the species’ habitat preferences. It also sheds light on the intricate behaviors of whales, about which there is still much to discover.</p>



<h2 class="wp-block-heading" id="h-playful-behavior-among-whales">Playful behavior among whales</h2>



<p>Whales, despite their immense size, often engage in playful behavior, demonstrating both their intelligence and their social nature.&nbsp;</p>



<h3 class="wp-block-heading" id="h-breaching">Breaching</h3>



<p>One of the most dramatic and easily noticeable behaviors, a breach involves the whale leaping out of the water and then crashing back down with a splash. It's believed this may help to dislodge parasites or simply be a form of play.</p>



<h3 class="wp-block-heading" id="h-tail-slapping">Tail slapping</h3>



<p>Whales might slap their tails (flukes) on the water's surface. This can serve as a form of communication, a way to stun prey, or even just play.</p>



<h3 class="wp-block-heading" id="h-spyhopping">Spyhopping</h3>



<p>This is when a whale vertically pokes its head out of the water to take a look around, possibly to scout its surroundings.</p>



<h3 class="wp-block-heading" id="h-lobtailing">Lobtailing</h3>



<p>Similar to tail slapping, but the whale will stick its tail out of the water and wave it around before smacking it down.</p>



<h3 class="wp-block-heading" id="h-log-rolling">Log rolling</h3>



<p>Whales, especially young ones, are sometimes observed rolling around in the water, which can be a playful activity or a way to dislodge parasites.</p>



<h3 class="wp-block-heading" id="h-playing-with-seaweed">Playing with seaweed</h3>



<p>Some whales have been observed playing with seaweed, passing it between their fins or tossing it around.</p>



<h3 class="wp-block-heading" id="h-interacting-with-other-species">Interacting with other species</h3>



<p>Whales are known to occasionally interact playfully with other marine animals, such as dolphins. For example, orcas (killer whales) and dolphins have been seen playing together, chasing each other, and even sliding on each other's wakes.</p>



<h3 class="wp-block-heading" id="h-bubble-blowing">Bubble blowing</h3>



<p>Some whales will release a stream of bubbles as they swim, which could serve various purposes including hunting, communication, or simply play.</p>



<p>The reasons behind these behaviors aren't always clear and could be a combination of play, communication, and practical necessity. Nevertheless, these playful activities offer a glimpse into the complex social and cognitive lives of these magnificent marine mammals.</p>



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Whales roll in seaweed as a play toy and also use it for its antibacterial properties

Humpback whales have been engaging in a unique behavior involving...

<p>In a recent study, scientists from the University of Florida have unveiled the mysterious process of how hammerhead sharks, renowned for their peculiar head shape, undergo dramatic changes during their gestation. </p>



<p>“This is a look at how monsters form,” said Gareth Fraser, a UF professor of Biology who supervised the new study. “This is an insight into the development of a wonder of nature that we haven’t seen before and may not be able to see again.”</p>



<h2 class="wp-block-heading" id="h-surprising-transformations-nbsp">Surprising transformations&nbsp;</h2>



<p>The research highlighted the surprising transformations that bonnethead shark <a href="https://www.earth.com/news/baby-birds-can-learn-sounds-before-birth/">embryos</a>, a species of hammerhead, experience during their growth.&nbsp;</p>



<p>Approximately mid-gestation, these two-inch-long embryos begin to widen their heads drastically. This expansion pushes their developing eyes outwards, creating an eerie and unnatural appearance.&nbsp;</p>



<p>Subsequently, the front of this "hammer" shape continues to evolve, moving backward toward the gills until it takes on a shovel-like form. A few months post this transformation, a foot-long shark emerges into the world.</p>



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



<p>Steven Byrum, a graduate student, teamed up with Professor Fraser to lead this detailed investigation of bonnetheads, which are abundant in the Gulf of Mexico and the Atlantic Ocean. Given their proximity to the shore, bonnetheads provide a unique opportunity for study.</p>



<p>What makes this study even more remarkable is the inherent challenges in studying the development of hammerheads. Unlike many fish and sharks that lay eggs, which can be studied in a controlled lab environment, hammerheads give birth to live young.&nbsp;</p>



<p>This natural process, combined with the endangered status of many shark species, prevents the harvesting of sharks for developmental research. To conduct this study without causing harm to additional sharks, Fraser’s team utilized preserved embryos from bonnetheads obtained during other biological research endeavors.</p>



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



<p>"It’s the perfect qualities of the bonnethead that allowed us to do it with this species," said Byrum. "This was a unique opportunity we may not be able to get for very much longer with bonnetheads and may not be able to get in any other species of hammerhead.”</p>



<p>The study was a collaborative effort that involved Gavin Naylor, director of the Florida Program for Shark Research at the Florida Museum of Natural History, as well as scientists from the South Carolina Department of Natural Resources and Florida State University.</p>



<h2 class="wp-block-heading" id="h-future-research-nbsp">Future research&nbsp;</h2>



<p>This documentation now paves the way for future experiments. The researchers hope to uncover the mechanisms that govern the hammerhead's head shape evolution and to decipher the evolutionary reasons behind their unique features, which are believed to enhance their visual field and ability to detect the electrical movements of their prey.</p>



<p>"Documenting the development of hard-to-access vertebrates, like this viviparous shark species, offers important information about how new and diverse morphologies arise that otherwise may remain poorly studied," wrote the researchers.</p>



<p>"This work will serve as a platform for future comparative developmental research both within sharks and across the phylogeny of vertebrates, underpinning the extreme potential of craniofacial development and morphological diversity in vertebrate animals."</p>



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



<p>Hammerhead sharks are a distinctive group of sharks known for their unique, hammer-like head shape which is called a "cephalofoil." This unusual structure provides them with several advantages in their marine environment:</p>



<h3 class="wp-block-heading" id="h-species">Species</h3>



<p>There are nine recognized species of hammerhead sharks, including the well-known great hammerhead, scalloped hammerhead, and the bonnethead. Each species varies in size, habitat, and behavior.</p>



<h3 class="wp-block-heading" id="h-physical-characteristics">Physical Characteristics</h3>



<h4 class="wp-block-heading" id="h-cephalofoil">Cephalofoil</h4>



<p>The hammer-shaped head improves their maneuverability, allowing them to make sharp turns quickly.</p>



<h4 class="wp-block-heading" id="h-eyes">Eyes</h4>



<p>Their eyes are positioned on the ends of the cephalofoil, providing a wide field of vision and improved depth perception.</p>



<h4 class="wp-block-heading" id="h-size">Size</h4>



<p>Hammerheads range in size, with smaller species like the bonnethead measuring around 3 to 4 feet long, while larger species like the great hammerhead can grow up to 20 feet.</p>



<h3 class="wp-block-heading" id="h-habitat-and-distribution">Habitat and distribution</h3>



<p>Hammerhead sharks are found worldwide in warmer waters along coastlines and continental shelves. They typically prefer temperatures ranging from 20 to 30 degrees Celsius (68 to 86 degrees Fahrenheit).</p>



<h3 class="wp-block-heading" id="h-behavior">Behavior</h3>



<p>Some species, like the scalloped hammerhead, often swim in schools, which is unusual for most shark species.</p>



<p>Despite their occasional schooling behavior, hammerheads usually hunt alone, using their cephalofoil to scan the ocean floor for prey.</p>



<h3 class="wp-block-heading" id="h-diet">Diet</h3>



<p>Hammerheads primarily feed on fish, including other sharks, as well as squid, octopus, and crustaceans. Their wide-set eyes give them a better visual range to locate prey, while the cephalofoil assists in trapping stingrays, one of their favorite meals, against the seafloor.</p>



<h3 class="wp-block-heading" id="h-conservation">Conservation</h3>



<p>Many species of hammerhead sharks are classified as endangered or vulnerable due to overfishing and the global shark fin trade. Conservation efforts are ongoing to protect these unique and important marine predators, including establishing shark sanctuaries and implementing fishing regulations.</p>



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



<p>As mentioned previously, hammerheads give birth to live young. Depending on the species, a female can give birth to a litter ranging from 6 to 42 pups every two years.</p>



<h3 class="wp-block-heading" id="h-hunting-behavior">Hunting behavior</h3>



<p>The cephalofoil is also believed to house a large number of electroreceptors, allowing hammerhead sharks to effectively detect the electrical signals emitted by other marine organisms, making them highly efficient predators.</p>



<p>Understanding and protecting hammerhead sharks is crucial due to their role in maintaining the health and balance of their marine ecosystems. The study by the University of Florida offers valuable insights into their developmental process, adding to the body of knowledge necessary for their conservation and management.</p>



<p>The research is published in the journal <a href="http://dx.doi.org/10.1002/dvdy.658" target="_blank" rel="noreferrer noopener"><em>Developmental Dynamics</em></a><em>.</em></p>



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Making a monster: The bizarre development of hammerhead sharks

In a recent study, scientists from the University of Florida...

<p>As our planet faces escalating challenges from global warming, a group of international scientists will be recruiting a surprising ally in the fight against <a href="https://www.earth.com/news/greenhouse-gas-emissions-reach-another-all-time-high/">greenhouse emissions</a>: the cow.&nbsp;</p>



<p>At the University of Illinois Urbana-Champaign, experts in animal sciences are launching a novel venture aimed at cutting methane emissions due to rumen fermentation in beef and dairy cattle.&nbsp;</p>



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



<p>Spanning three years and backed by a $3.2-million budget, this undertaking falls under the umbrella of the <a href="https://foundationfar.org/consortia/greener-cattle-initiative/">Greener Cattle Initiative</a>, which is backed by the Foundation for Food and Agriculture Research (FFAR).</p>



<p>Research data indicates that taking on methane might be a faster route to addressing climate issues than solely focusing on carbon dioxide (CO2). Methane’s heat-trapping ability is 28 times stronger than CO2’s, but it exits the atmosphere in roughly a dozen years, while CO2 can linger for centuries.</p>



<p>“What this means is that anything we do now with ruminant animals can have a huge impact on warming within decades, rather than centuries. Our challenge is to reduce enteric methane emissions by about 30 to 40 percent with the technologies we have,” said project leader Rod Mackie, a professor in the Department of Animal Sciences at U of I.&nbsp;</p>



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



<p>Connecting six research centers globally, this project zeroes in on enteric methane – a byproduct of microbial fermentation in the rumen. As a part of this strategy, Mackie and his colleagues aim to examine hydrogen’s role during fermentation.</p>



<p>During the fermentation process, the recycling of an energy-rich molecule, NADH, stands out. For the uninterrupted generation of energy, NADH must release its hydrogen and anticipate a replacement from the decomposition of carbohydrates. Generally, NADH’s surplus hydrogen aids in turning CO2 into methane. Yet, the scientists speculate that there are alternatives to use this type of hydrogen.</p>



<p>“In anaerobic fermentation in the rumen, you have to have some way of recycling hydrogen through the conversion of NADH to NAD. In that process, most of the excess hydrogen goes towards methane. If you shut down methane production, hydrogen builds up and inhibits glycolysis,” Mackie explained.&nbsp;</p>



<p>“We don’t want that to happen. Instead, we want to redirect hydrogen into other products, such as propionate and butyrate, reduced fatty acids that serve as the primary energy source for all ruminants.”</p>



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



<p>“There are a lot of groups working on inhibiting methane directly using dietary additives. Our focus is trying to figure out how we actually make it work in an animal and make it more energetically feasible. That’s really been the missing piece,” added Josh McCann, an assistant professor of Animal Sciences at the same university, who will also be involved in the project.&nbsp;</p>



<p>“If cows can’t metabolize the excess hydrogens for productive benefit and to improve growth, there will continue to be limited adoption of methane reduction strategies or additives. There’s no economic incentive.”</p>



<h2 class="wp-block-heading" id="h-microbial-communities-nbsp">Microbial communities&nbsp;</h2>



<p>The team’s strategy begins in the lab through a thorough investigation of hydrogen production and its utilization. By examining rumen microbial communities from diverse cattle, the researchers aim to uncover potential tweaks using inhibitor compounds. Their findings will eventually be tested on cattle.</p>



<p>“Most of the grant is focused on the basic and the mechanistic side, but once we make something that might work within a microbial community, it still has to work in an animal,” McCann explained.&nbsp;</p>



<h2 class="wp-block-heading" id="h-methane-inhibitor-nbsp">Methane inhibitor&nbsp;</h2>



<p>“We have complicating factors like diet components and how much they want to eat. Not to mention dairy cattle and beef cattle are eating different things, so the bugs in the rumen function differently. So, if we apply a methane inhibitor to a dairy microbial community, we might have to approach the hydrogen capture a little bit differently than in a beef rumen community.”</p>



<p>Mackie envisions this initiative as the starting point of a long-term quest to tackle enteric methane. By the conclusion of the three-year project, the experts aim to pinpoint precise inhibitor dosages that either maintain or even bolster production capacities.</p>



<p>“What we’d like is to have ruminants save the planet within 10 years. That would be amazing,” Mackie concluded.</p>



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<p>Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by <a href="https://www.linkedin.com/in/eric-ralls/">Eric Ralls</a> and <a href="https://www.earth.com/">Earth.com</a>.</p>



<p>.</p>

Greener cattle: Seeking ways to inhibit methane production in cows

As our planet faces escalating challenges from global warming, a...

Hallaxa translucens

Taxonomic tree: