ScienceBlogs - Where the world discusses science https://scienceblogs.com/ en Crowdsourced Geospatial Data Will Mean A 'Seismic Shift' https://scienceblogs.com/sb-admin/2024/02/01/crowdsourced-geospatial-data-will-mean-seismic-shift-151462 <span>Crowdsourced Geospatial Data Will Mean A &#039;Seismic Shift&#039;</span> <div class="field field--name-body field--type-text-with-summary field--label-hidden field--item"><p>Astronomy has long been dominated by expert amateurs but with geospatial data everywhere, thanks to widely available internet and smartphones, it is not just that directions that were once only available in a paper map are now updated on your phone in real time to account for traffic.</p> <p>It is changing the relationships of science also. Crowdsourced scientific data will go from obscure folding protein folding of 15 years ago <a href="https://spj.science.org/doi/abs/10.34133/remotesensing.0105?adobe_mc=MCMID%3D62622146414290904453948534714310658743%7CMCORGID%3D242B6472541199F70A4C98A6%2540AdobeOrg%7CTS%3D1706843891">to relevance everywhere</a>.</p> <p>That evolution will continue to be driven by how the data is gathered.</p> <p><img src="https://scienceblogs.com/files/blogs/geospatial%20crowdsourcing.jpeg" /></p> <p><em>Credit: Xiao Huang, Emory University</em></p> <p> </p> <p>According to the authors, urban planning, transportation and environmental monitoring have been particularly impacted by crowdsourcing information, with “unprecedented real-time sights and community-driven perspectives, often leading to more responsive and adaptive decision-making processes,” thanks to user-generated data.</p> <p> </p> <p>The same type of data is informing the commercial sector, as well, with better-informed customer-centric product development and marketing strategies. The significance of this shift lies in its empowerment of ordinary individuals to contribute to and influence fields traditionally dominated by experts and authorities. This democratization has not only diversified the types of data available but has also led to richer, more multifaceted insighted into human behavior and environmental changes.</p> <p> </p> <p>Despite such a shift, however, the researchers said a comprehensive, overarching perspective to connect the various data sources, such as social media platforms, with the application domains, such as public health or remote sensing, is still needed.</p> <p> </p> <p>“We aim to bridge this gap and provide a holistic view of the use and potential of crowdsourcing geospatial data,” said Emory University professor Xiao Huang. “In this study, we conduct an exhaustive analysis of the current efforts, possibilities and obstacles associated with crowdsourced geospatial data across two fundamental perspectives: human observations and Earth observations.”</p> <p> </p> <p>Earth observations refers to the work of large entities, such as academic institutions or government bodies to record data, as opposed to human observations made on social media, for example. In coupling these two perspectives, the researchers identified seven specific challenges: ensuring data quality and accuracy; protecting data privacy; training and educating non-experts; sustaining data collection; navigating legal and ethical issues; and interpreting data. Their paper summarizes the current state of affairs in each area, as well as a potential pathway forward.</p> <p> </p> <p>“Crowdsourced geospatial data has a critical role and vast potential in enhancing human and Earth observations,” Huang said. “This data, contributed by the general public through various platforms, offers high-resolution spatiotemporal observations that traditional methods might miss. This comprehensive review paper underscores the democratization of data collection and its implications for various sectors, emphasizing the necessity of integrating these non-traditional data sources for more comprehensive and nuanced understanding and decision making.”</p> <p> </p> <p>The researchers identified three primary future directions: expanding the scope of geospatial crowdsourcing by harnessing the power of the crowd; pioneering a sustainable crowdsourcing ecosystem, from motivation to retention; and translating crowdsourced geospatial data into real-world impact.</p></div> <span><a title="View user profile." href="/author/sb-admin" lang="" about="/author/sb-admin" typeof="schema:Person" property="schema:name" datatype="">sb admin</a></span> <span>Thu, 02/01/2024 - 22:10</span> <div class="field field--name-field-blog-categories field--type-entity-reference field--label-inline"> <div class="field--label">Categories</div> <div class="field--items"> <div class="field--item"><a href="/channel/technology" hreflang="en">Technology</a></div> </div> </div> Fri, 02 Feb 2024 03:10:51 +0000 sb admin 151462 at https://scienceblogs.com Red Light Myopia Therapy Can Injure Your Retina https://scienceblogs.com/sb-admin/2024/01/29/red-light-myopia-therapy-can-injure-your-retina-151461 <span>Red Light Myopia Therapy Can Injure Your Retina</span> <div class="field field--name-body field--type-text-with-summary field--label-hidden field--item"><p>Over the last few years, low-level red light (LLRL) therapy has become popular to control myopia, or nearsightedness, especially in children. In LLRL therapy, children are instructed to look into a red light-emitting instrument for three minutes, twice a day, five days a week, for the duration of the treatment period, which could last years. </p> <p> </p> <p>Studies reported the treatment as effective and responsible for significant reduction in myopia progression and it is already being used to address myopia in over 100,000 pediatric patients.  </p> <p> </p> <p>Despite passing clinical trials it's not safe in all cases, so stricter standards need to be created, according to University of Houston Professor Lisa Ostrin, who says <a href="https://onlinelibrary.wiley.com/doi/10.1111/opo.13272">the therapy can put the retina at risk of photochemical and thermal damage</a>. </p> <p> </p> <p><img src="https://scienceblogs.com/files/blogs/level%20red%20light%20LLRL%20therapy.jpg" />Photo courtesy of GETTY Images, provided by the University of Houston</p> <p> </p> <p>Ostrin examined two different LLRL devices, and while both instruments were confirmed to be Class-1 laser products, as defined by International Electrotechnical Commission standards, according to Ostrin they are unsafe to view continuously for the required treatment duration of three minutes.  </p> <p> </p> <p>Class-1 lasers are low-powered devices that are considered safe from all potential hazards when viewed accidentally and briefly. Examples of Class-1 lasers are laser printers, CD players and digital video disc (DVD) devices. Class-1 lasers are not meant to be viewed directly for extended periods. </p> <p> </p> <p> “We found that the red-light instruments for myopia exceed safety limits,” said Ostrin. “For both LLRL devices evaluated here, three minutes of continuous viewing approached or surpassed the luminance dose MPE, putting the retina at risk of photochemical damage.” </p></div> <span><a title="View user profile." href="/author/sb-admin" lang="" about="/author/sb-admin" typeof="schema:Person" property="schema:name" datatype="">sb admin</a></span> <span>Mon, 01/29/2024 - 14:18</span> <div class="field field--name-field-blog-categories field--type-entity-reference field--label-inline"> <div class="field--label">Categories</div> <div class="field--items"> <div class="field--item"><a href="/channel/medicine" hreflang="en">Medicine</a></div> </div> </div> Mon, 29 Jan 2024 19:18:47 +0000 sb admin 151461 at https://scienceblogs.com No, COVID-19 Vaccines Do Not Cause Infertility - Not Getting It Might https://scienceblogs.com/sb-admin/2022/01/20/no-covid-19-vaccines-do-not-cause-infertility-not-getting-it-might-151460 <span>No, COVID-19 Vaccines Do Not Cause Infertility - Not Getting It Might</span> <div class="field field--name-body field--type-text-with-summary field--label-hidden field--item"><p>Despite claims of anti-vaccine activists no different than groups that used to claim vaccines cause autism, COVID-19 vaccines do not impact fecundability—the probability of conception per menstrual cycle—in female or male partners who received the Pfizer-BioNTech, Moderna, or Johnson &amp; Johnson vaccines.</p> <p><a href=" Boston University School of Public Health ">The prospective study</a> instead indicates that COVID-19 infection among males may temporarily reduce fertility— an outcome that could be avoidable through vaccination.</p> <p>Lead author Dr. Amelia Wesselink, epidemiologist at  Boston University School of Public Health, and colleagues analyzed survey data on COVID-19 vaccination and infection, and fecundability, among female and male participants in the BUSPH-based Pregnancy Study Online (PRESTO), an ongoing NIH-funded study that enrolls women trying to conceive, and follows them from preconception through six months after delivery. Participants included 2,126 women in the US and Canada who provided information on sociodemographics, lifestyle, medical factors, and characteristics of their partners from December 2020 to September 2021, and the participants were followed in the study through November 2021.</p> <p>The researchers calculated the per menstrual cycle probability of conception using self-reported dates of participants’ last menstrual period, typical menstrual cycle length, and pregnancy status. Fertility rates among female participants who received at least one dose of a vaccine were nearly identical to unvaccinated female participants. Fecundability was also similar for male partners who had received at least one dose of a COVID-19 vaccine compared with unvaccinated male participants. Additional analyses that considered the number of vaccine doses, brand of vaccine, infertility history, occupation, and geographic region also indicated no effect of vaccination on fertility.</p> <p>While COVID-19 infection was not strongly associated with fertility, men who tested positive for COVID within 60 days of a given cycle had reduced fertility compared to men who never tested positive, or men who tested positive at least 60 days prior. This data supports previous research that has linked COVID-19 infection in men with poor sperm quality and other reproductive dysfunction.</p> <p>“These data provide reassuring evidence that COVID vaccination in either partner does not affect fertility among couples trying to conceive,” says study senior author Dr. Lauren Wise, professor of epidemiology at BUSPH. “The prospective study design, large sample size, and geographically heterogeneous study population are study strengths, as was our control for many variables such as age, socioeconomic status, preexisting health conditions, occupation, and stress levels.”</p> <p>The new data also help quell concerns about COVID-19 vaccines and fertility that arose from anecdotal reports of females experiencing menstrual cycle changes following vaccination.</p></div> <span><a title="View user profile." href="/author/sb-admin" lang="" about="/author/sb-admin" typeof="schema:Person" property="schema:name" datatype="">sb admin</a></span> <span>Thu, 01/20/2022 - 20:17</span> <div class="field field--name-field-blog-categories field--type-entity-reference field--label-inline"> <div class="field--label">Categories</div> <div class="field--items"> <div class="field--item"><a href="/channel/medicine" hreflang="en">Medicine</a></div> </div> </div> Fri, 21 Jan 2022 01:17:23 +0000 sb admin 151460 at https://scienceblogs.com Liangzhu, Venice of the Stone Age, Collapsed Due To Climate Change https://scienceblogs.com/sb-admin/2021/12/02/liangzhu-venice-stone-age-collapsed-due-climate-change-151459 <span>Liangzhu, Venice of the Stone Age, Collapsed Due To Climate Change</span> <div class="field field--name-body field--type-text-with-summary field--label-hidden field--item"><p>In the Yangtze Delta, about 160 kilometres southwest of Shanghai, the archeological ruins of Liangzhu City are located. There, a highly advanced culture blossomed about 5,300 years ago, thanks to the engineering of large hydraulic structures.</p> <p>The walled city had a complex system of navigable canals, dams and water reservoirs. This system made it possible to cultivate very large agricultural areas throughout the year. In the history of human civilization, it is one of the first examples of highly developed communities based on a water infrastructure.</p> <p>And they did it all without metal.</p> <p>Long undiscovered, the archaeological site is now considered a well-preserved record of Chinese civilisation dating back more than 5000 years and was declared a UNESCO World Heritage Site in 2019. However, the advanced civilization of this city came to an abrupt end.</p> <p>"A thin layer of clay was found on the preserved ruins, which points to a possible connection between the demise of the advanced civilization and floods of the Yangtze River or floods from the East China Sea. No evidence could be found for human causes such as warlike conflicts," explains Christoph Spötl of the University of Innsbruck. </p> <p><img src="https://scienceblogs.com/files/blogs/dripstones%20of%20Shennong%20Cave.jpg" width="600" /><br /><em>The dripstones of Shennong Cave (pictured) and Jiulong Cave provide an accurate glimpse into the time of the Liangzhu culture's collapse about 4300 years ago. Credit: Haiwei Zhang</em></p> <h2><strong>Dripstones store the answer</strong></h2> <p>Caves and their deposits, such as dripstones, are among the most important climate archives that exist. They allow the reconstruction of climatic conditions above the caves up to several 100,000 years into the past. Since it is still not clear what caused the sudden collapse of the Liangzhu culture, the research team searched for suitable archives in order to investigate a possible climatic cause of this collapse.</p> <p>Geologist Haiwei Zhang from Xi'an Jiaotong University in Xi'an took samples of stalagmites from the two caves Shennong and Jiulong, which are located southwest of the excavation site.</p> <p>Data from the stalagmites show that between 4345 and 4324 years ago there was a period of extremely high precipitation. Evidence for this was provided by the isotope records of carbon, which were measured at the University of Innsbruck. The precise dating was done by uranium-thorium analyses at Xi'an Jiaotong University, whose measurement accuracy is ± 30 years.</p> <p>The massive monsoon rains probably led to such severe flooding of the Yangtze and its branches that even the sophisticated dams and canals could no longer withstand these masses of water, destroying Liangzhu City and forcing people to flee. The very humid climatic conditions continued intermittently for another 300 years, as the geologists show from the cave data.</p> <p>Citation: Haiwei Zhang, Hai Cheng, Ashish Sinha, Christoph Spötl, Yanjun Cai et al. <strong>Collapse of the Liangzhu and other Neolithic cultures in the lower Yangtze region in response to climate change</strong>. <em>Sci. Adv.</em>, 2021 DOI: <a href="http://dx.doi.org/10.1126/sciadv.abi9275">10.1126/sciadv.abi9275</a></p></div> <span><a title="View user profile." href="/author/sb-admin" lang="" about="/author/sb-admin" typeof="schema:Person" property="schema:name" datatype="">sb admin</a></span> <span>Thu, 12/02/2021 - 03:41</span> <div class="field field--name-field-blog-categories field--type-entity-reference field--label-inline"> <div class="field--label">Categories</div> <div class="field--items"> <div class="field--item"><a href="/channel/physical-sciences" hreflang="en">Physical Sciences</a></div> </div> </div> Thu, 02 Dec 2021 08:41:56 +0000 sb admin 151459 at https://scienceblogs.com Genetically Rescued Organism: Toward A Solution For Sudden Oak Death https://scienceblogs.com/sb-admin/2021/11/08/genetically-rescued-organism-toward-solution-sudden-oak-death-151458 <span>Genetically Rescued Organism: Toward A Solution For Sudden Oak Death</span> <div class="field field--name-body field--type-text-with-summary field--label-hidden field--item"><p>Sudden oak death, caused by the pathogen <em>Phythophthora ramorum</em>, is one of the most ecologically devastating forest diseases in North America, responsible for the deaths of millions of oaks and tanoaks along the coast.</p> <p>Science to the rescue? After the success of genetically modified organisms in things like insulin and food, a recent trend is <a href="https://www.science20.com/hank_campbell/gros_genetically_rescued_organisms_will_save_plant_species_at_risk-238881">Genetically Rescued Organisms</a>. These GROs would use science to create natural resistance, like a vaccine for plants, and reduce the impact of altered species composition, released carbon pools, and greater fire risk the deaths bring.</p> <p>Before that can happen, scientists need to better understand the basic biology of <em>Phythophthora ramorum</em>, including how well it sporulates on common plants.</p> <p><img src="https://scienceblogs.com/files/blogs/oak%20tree.png" width="600" /><br /> Image by RegalShave from Pixabay</p> <p>Scientists at the University of California, Davis, set out to <a href="https://apsjournals.apsnet.org/doi/full/10.1094/PDIS-03-20-0485-RE">investigate the sporulation potential of this pathogen on common California plant species</a>. They collected leaves from 13 common plant hosts in the Big Sur-region and inoculated them with the causal pathogen. They found that most of the species produced spores, though there was a ride range, with bay laurel and tanoak producing significantly more sporangia than the other species. They also observed an inconsistent relationship between sporulation and lesion size, indicating that visual symptoms are not a reliable metric of sporulation potential.</p> <p> “Our study is the first to investigate the sporulation capacity on a wide range of common coastal California native plant species and with a large enough sample size to statistically distinguish between species," explained first author Dr. Lisa Rosenthal. "It largely confirms what was previously reported in observational field studies – that tanoak and bay laurel are the main drivers of sudden oak death infections—but also indicates that many other hosts are capable of producing spores.”</p> <p>Citation: Lisa M. Rosenthal, Sebastian N. Fajardo, and David M. Rizzo, <a href="https://apsjournals.apsnet.org/doi/abs/10.1094/PDIS-03-20-0485-RE">Sporulation Potential of <em>Phytophthora ramorum</em> Differs Among Common California Plant Species in the Big Sur Region</a>, Plant Disease 17 Aug 2021 <a href="https://doi.org/10.1094/PDIS-03-20-0485-RE">https://doi.org/10.1094/PDIS-03-20-0485-RE</a></p></div> <span><a title="View user profile." href="/author/sb-admin" lang="" about="/author/sb-admin" typeof="schema:Person" property="schema:name" datatype="">sb admin</a></span> <span>Mon, 11/08/2021 - 17:47</span> <div class="field field--name-field-blog-categories field--type-entity-reference field--label-inline"> <div class="field--label">Categories</div> <div class="field--items"> <div class="field--item"><a href="/channel/life-sciences" hreflang="en">Life Sciences</a></div> </div> </div> Mon, 08 Nov 2021 22:47:18 +0000 sb admin 151458 at https://scienceblogs.com Doomscrolling COVID-19 News Takes an Emotional Toll - Here is How to Prevent That https://scienceblogs.com/sb-admin/2021/10/22/doomscrolling-covid-19-news-takes-emotional-toll-here-how-prevent-151457 <span>Doomscrolling COVID-19 News Takes an Emotional Toll - Here is How to Prevent That</span> <div class="field field--name-body field--type-text-with-summary field--label-hidden field--item"><p>Picture this: it’s April 2020, you’re between Zoom meetings, and scrolling through your social media newsfeed. Headlines like “Death toll continues to rise”, “COVID-19 may cause long-term health implications” and “Health-care systems overwhelmed” flash across your screen. Your mood takes a dive, but you can’t stop scrolling.</p> <p>If this scenario rings true for you, you’re not alone. <a href="https://journals.sagepub.com/doi/10.1177/1075547012441873">Research shows</a> people have a tendency to seek out information during uncertain times – it’s a natural coping mechanism. But is persistent information-seeking on social media, sometimes called doomscrolling, helpful during a pandemic, or any time?</p> <p>Research on the effects of bad news on mood <a href="https://www.tandfonline.com/doi/abs/10.1080/1461670X.2018.1545599?journalCode=rjos20">more generally</a> suggest exposure to negative COVID news is likely to be detrimental to our emotional wellbeing. And indeed, early evidence on the effects of COVID news consumption on mental distress reflected this. For instance, <a href="https://www.ajpmonline.org/article/S0749-3797(20)30274-9/fulltext">one study</a> conducted in March 2020 involving more than 6,000 Americans found that the more time participants spent consuming COVID news in a day, the unhappier they felt.</p> <p>These findings are striking but leave a few key questions unanswered. Does doomscrolling make people unhappy, or are unhappy people just more likely to doomscroll? How much time spent doomscrolling is a problem? And what would happen if, instead of doomscrolling, we were “kindness scrolling” – reading about humanity’s positive responses to a global crisis?</p> <p>To find out, we conducted <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0257728">a study</a> where we showed hundreds of people real-world content on either Twitter or YouTube for two to four minutes. The Twitter feeds and YouTube videos featured either general news about COVID, or news about kindness during COVID. We then measured these participants’ moods using a questionnaire, and compared their moods with participants who did not engage with any content at all.</p> <p>People who were shown general COVID-related news experienced lower moods than people who were shown nothing at all. Meanwhile, people who were shown COVID news stories involving acts of kindness didn’t experience the same decline in mood, but also didn’t gain the boost in mood we’d predicted.</p> <p>These findings suggest that spending as little as two to four minutes consuming negative news about COVID-19 can have a detrimental impact on our mood.</p> <p>Although we didn’t see an improvement in mood among participants who were shown positive news stories involving acts of kindness, this may be because the stories were still related to COVID. In <a href="https://www.tandfonline.com/doi/abs/10.1080/1461670X.2018.1545599?journalCode=rjos20">other research</a>, positive news stories have been associated with improvements in mood.</p> <h2>Making your social media a more positive place</h2> <p>Our research was published earlier this month. Ironically, <a href="https://www.dailymail.co.uk/sciencetech/article-10092677/Just-two-MINUTES-doomscrolling-social-media-bring-mood-study-warns.html">news coverage</a> of our findings, with <a href="https://www.thesun.co.uk/news/16415543/social-media-miserable-study/">headlines such as</a> “Just five minutes spent on social media is enough to make you miserable, study finds”, could be part of a person’s doomscrolling content.</p> <p>But we didn’t find that all social media use makes people miserable. Rather, we found that consuming negative content about COVID via Twitter or YouTube in the midst of a pandemic does.</p> <p>So what can we do to look after ourselves, and make our time on social media more pleasurable?</p> <p><img alt="doomscrolling and mood" data-entity-type="file" data-entity-uuid="49c82161-abfc-4e81-8038-c9ba2217b360" src="/files/inline-images/Doomscrolling%202.jpg" /></p> <p><em><span>We found that just a few minutes consuming negative news about COVID-19 can have a detrimental impact on our mood.</span> <span><a href="https://www.shutterstock.com/image-photo/top-view-laptop-girls-hands-sitting-314921831">Nuchylee/Shutterstock</a></span></em></p> <p> </p> <p>One option is to delete our social media accounts altogether. Figures show almost half of Facebook users in <a href="https://www.statista.com/statistics/1059283/users-leaving-social-networks-uk/">the UK</a> and <a href="https://www.statista.com/statistics/262145/us-social-networkers-who-want-use-social-networking-less/">the US</a> considered leaving the platform in 2020.</p> <p>But how realistic is it to distance ourselves from platforms that connect <a href="https://www.oberlo.co.uk/blog/social-media-marketing-statistics">nearly half</a> of the world’s population, particularly when these platforms offer social interactions at a time when face-to-face interactions can be risky, or impossible?</p> <p>Given that avoidance might not be practical, here are some other ways to make your experience on social media more positive.</p> <ol><li> <p>Be mindful of what you consume on social media. If you log on to connect with other people, focus on the personal news and photos shared instead of the latest headlines.</p> </li> <li> <p>Seek out content that makes you happy to balance out your newsfeed. This may be images of cute kittens, beautiful landscapes, drool-worthy food videos or something else. You could even follow a social media account dedicated to sharing only happy and positive news.</p> </li> <li> <p>Use social media to promote positivity and kindness. Sharing good things that are happening in your life can <a href="http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.712.9449&amp;rep=rep1&amp;type=pdf">improve your mood</a>, and your positive mood can spread to others. You may also like to <a href="https://hbr.org/2021/02/a-simple-compliment-can-make-a-big-difference?autocomplete=true">compliment others</a> on social media. While this might sound awkward, people will appreciate it more than you think.</p> </li> </ol><p>Importantly, we’re not suggesting that you avoid all news and negative content. We need to know what’s happening in the world. However, we should also be mindful of our mental health.</p> <p>As the pandemic continues to alter our lives and newsfeeds, our findings highlight the importance of being aware of the emotional toll negative news takes on us. But there are steps we can take to mitigate this toll and make our social media a happier place.</p> <p><span>By <a href="https://theconversation.com/profiles/kathryn-buchanan-149009">Kathryn Buchanan</a>, Lecturer, Psychology Department, <em><a href="https://theconversation.com/institutions/university-of-essex-1291">University of Essex</a></em>; <a href="https://theconversation.com/profiles/gillian-sandstrom-1283157">Gillian Sandstrom</a>, Senior Lecturer, Department of Psychology, <em><a href="https://theconversation.com/institutions/university-of-essex-1291">University of Essex</a></em>; <a href="https://theconversation.com/profiles/lara-aknin-1283155">Lara Aknin</a>, Distinguished Associate Professor of Psychology, <em><a href="https://theconversation.com/institutions/simon-fraser-university-1282">Simon Fraser University</a></em>, and <a href="https://theconversation.com/profiles/shaaba-lotun-1283263">Shaaba Lotun</a>, PhD candidate, Department of Psychology, <em><a href="https://theconversation.com/institutions/university-of-essex-1291">University of Essex</a>. </em></span>This article is republished from <a href="https://theconversation.com">The Conversation</a> under a Creative Commons license. Read the <a href="https://theconversation.com/doomscrolling-covid-news-takes-an-emotional-toll-heres-how-to-make-your-social-media-a-happier-place-170342">original article</a>.</p> <p><img alt="The Conversation" height="1" src="https://counter.theconversation.com/content/170342/count.gif?distributor=republish-lightbox-basic" width="1" /></p></div> <span><a title="View user profile." href="/author/sb-admin" lang="" about="/author/sb-admin" typeof="schema:Person" property="schema:name" datatype="">sb admin</a></span> <span>Fri, 10/22/2021 - 18:03</span> <div class="field field--name-field-blog-categories field--type-entity-reference field--label-inline"> <div class="field--label">Categories</div> <div class="field--items"> <div class="field--item"><a href="/channel/social-sciences" hreflang="en">Social Sciences</a></div> </div> </div> Fri, 22 Oct 2021 22:03:40 +0000 sb admin 151457 at https://scienceblogs.com Appreciating van Leeuwenhoek: The Cloth Merchant Who Discovered Microbes https://scienceblogs.com/sb-admin/2021/04/06/appreciating-van-leeuwenhoek-cloth-merchant-who-discovered-microbes-151456 <span>Appreciating van Leeuwenhoek: The Cloth Merchant Who Discovered Microbes</span> <div class="field field--name-body field--type-text-with-summary field--label-hidden field--item"><p>Imagine trying to cope with a pandemic like COVID-19 in a world where microscopic life was unknown. Prior to the 17th century, people were limited by what they could see with their own two eyes. But then a Dutch cloth merchant changed everything.</p> <p>His name was Antonie van Leeuwenhoek, and he lived from 1632 to 1723. Although untrained in science, Leeuwenhoek became the greatest lens-maker of his day, discovered microscopic life forms and is <a href="https://makingscience.royalsociety.org/s/rs/people/fst00039851">known today as the “father of microbiology.”</a></p> <h2>Visualizing ‘animalcules’ with a ‘small see-er’</h2> <p><img alt="Antonie van Leeuwenhoek" data-entity-type="file" data-entity-uuid="066d213f-6e51-446d-aa60-b5b9bf1fd3bc" src="/files/inline-images/van%20Leeuwenhoek.jpg" /></p> <p><span>Leeuwenhoek opened the door to a vast, previously unseen world.</span> <span><a href="https://wellcomecollection.org/works/ft6mf62b">J. Verolje/Wellcome Collection</a>, <a href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></p> <p>Leeuwenhoek didn’t set out to identify microbes. Instead, he was trying to assess the quality of thread. He developed <a href="https://micro.magnet.fsu.edu/primer/museum/leeuwenhoek.html">a method for making lenses</a> by heating thin filaments of glass to make tiny spheres. His lenses were of such high quality he saw things no one else could.</p> <p>This enabled him to train his microscope – literally, “small see-er” – on a new and largely unexpected realm: objects, including organisms, far too small to be seen by the naked eye. He was the <a href="https://ucmp.berkeley.edu/history/leeuwenhoek.html">first to visualize red blood cells, blood flow in capillaries and sperm</a>.</p> <p><img alt="van Leeuwenhoek bacteria" data-entity-type="file" data-entity-uuid="72b6ea41-0f2e-48be-8a86-e965cd62a749" src="/files/inline-images/van%20Leeuwenhoek%20bacteria.jpg" /></p> <p><span>Drawings from a Leeuwenhoek letter in 1683 illustrating human mouth bacteria.</span> <span><a href="https://commons.wikimedia.org/wiki/File:Leuwenhoek_picture_of_animacules.png">Huydang2910</a>, <a href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></p> <p>Leeuwenhoek was also the <a href="https://www.aaas.org/discovery-bacteria">first human being to see a bacterium</a> – and the importance of this discovery for microbiology and medicine can hardly be overstated. Yet he was reluctant to publish his findings, due to his lack of formal education. Eventually, friends prevailed upon him to do so.</p> <p>He wrote, “Whenever I found out anything remarkable, I thought it <a href="https://ucmp.berkeley.edu/history/leeuwenhoek.html">my duty to put down my discovery on paper</a>, so that all ingenious people might be informed thereof.” He was guided by his curiosity and joy in discovery, asserting “I’ve taken no notice of those who have said <a href="https://laurieximenez.files.wordpress.com/2016/03/2-microbe-hunters-paul-de-kruif.pdf">why take so much trouble and what good is it</a>?”</p> <p>When he reported visualizing “animalcules” (tiny animals) swimming in a drop of pond water, members of the scientific community questioned his reliability. After his findings were <a href="https://doi.org/10.1098/rsnr.2004.0055">corroborated by reliable religious and scientific authorities</a>, they were published, and in 1680 he was invited to join the Royal Society in London, then the world’s premier scientific body.</p> <p>Leeuwenhoek was not the world’s only microscopist. In England, his contemporary <a href="https://theconversation.com/robert-hooke-the-english-leonardo-who-was-a-17th-century-scientific-superstar-119497">Robert Hooke coined the term “cell”</a> to describe the basic unit of life and published his “Micrographia,” featuring incredibly detailed images of insects and the like, which became the first scientific best-seller. Hooke, however, did not identify bacteria.</p> <p>Despite Leuwenhoek’s prowess as a lens-maker, even he could not see viruses. They are about 1/100th the size of bacteria, much too small to be visualized by light microscopes, which because of the physics of light <a href="http://www.auburn.edu/academic/classes/biol/4101/estridge2/tutorial1a.pdf">can magnify only thousands of times</a>. Viruses weren’t visualized until 1931 with the <a href="http://www.auburn.edu/academic/classes/biol/4101/estridge2/tutorial1a.pdf">invention of electron microscopes</a>, which could magnify by the millions.</p> <p><img alt="microscope dots" data-entity-type="file" data-entity-uuid="69e14bc5-2ddc-44ee-b849-202d13604df6" src="/files/inline-images/microscope%20dots.jpg" width="600" /></p> <p><span>An image of the hepatitis virus courtesy of the electron microscope.</span> <span><a href="https://newsroom.ap.org/detail/Hepatitis/20c83d41c4ef41a593761c96f6565697">E.H. Cook, Jr./CDC via Associated Press</a></span></p> <h2>A vast, previously unseen world</h2> <p>Leeuwenhoek and his successors opened up, by far, the largest realm of life. For example, all the bacteria on Earth <a href="https://www.vox.com/science-and-health/2018/5/29/17386112/all-life-on-earth-chart-weight-plants-animals-pnas">outweigh humans by more than 1,100 times</a> and outnumber us by an unimaginable margin. There is fossil evidence that <a href="https://ucmp.berkeley.edu/bacteria/bacteriafr.html">bacteria were among the first life forms on Earth</a>, dating back over 3 billion years, and today it is thought the planet houses about <a href="http://news.bbc.co.uk/2/hi/science/nature/158203.stm">5 nonillion (1 followed by 30 zeroes) bacteria</a>.</p> <p>Some species of <a href="https://sphweb.bumc.bu.edu/otlt/mph-modules/ph/ph709_infectiousagents/PH709_InfectiousAgents4.html">bacteria cause diseases</a>, such as cholera, syphilis and strep throat; while <a href="https://doi.org/10.3389/fmicb.2019.00780">others, known as extremophiles</a>, can survive at temperatures beyond the boiling and freezing points of water, from the upper reaches of the atmosphere to the deepest points of the oceans. Also, the number of harmless bacterial cells on and in our bodies <a href="https://www.nature.com/news/scientists-bust-myth-that-our-bodies-have-more-bacteria-than-human-cells-1.19136">likely outnumber the human ones</a>.</p> <p>Viruses, which include the coronavirus SARS-CoV-2 that causes COVID-19, outnumber bacteria by a factor of 100, meaning there are <a href="https://www.nationalgeographic.com/science/article/factors-allow-viruses-infect-humans-coronavirus">more of them on Earth than stars in the universe</a>. They, too, are found everywhere, from the upper atmosphere to the ocean depths.</p> <p><img alt="human rhinovirus" data-entity-type="file" data-entity-uuid="3bdc2455-4b6e-4d4d-a118-63b60bd4980f" src="/files/inline-images/human%20rhinovirus.png" width="600" /></p> <p><span>A visualization of the human rhinovirus 14, one of many viruses that cause the common cold. Protein spikes are colored white for clarity.</span> <span><a href="https://commons.wikimedia.org/wiki/File:Rhinovirus_isosurface.png">Thomas Splettstoesser</a>, <a href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></p> <p>Strangely, <a href="https://www.scientificamerican.com/article/are-viruses-alive-2004/">viruses probably do not qualify as living organisms</a>. They can replicate only by infecting other organisms’ cells, where they hijack cellular systems to make copies of themselves, sometimes causing the death of the infected cell.</p> <p>It is important to remember that microbes such as bacteria and viruses do far more than cause disease, and many are vital to life. For example, <a href="https://doi.org/10.1177/1535370217746612">bacteria synthesize vitamin B12</a>, without which most living organisms would not be able to make DNA.</p> <p>Likewise, viruses cause diseases such as the common cold, influenza and COVID-19, but they also play a vital role in transferring genes between species, which <a href="https://www.sciencedaily.com/releases/2016/07/160713100911.htm">helps to increase genetic diversity and propel evolution</a>. Today <a href="https://www.cancer.gov/news-events/cancer-currents-blog/2018/oncolytic-viruses-to-treat-cancer">researchers use viruses to treat diseases such as cancer</a>.</p> <p>Scientists’ understanding of microbes has progressed a long way since Leeuwenhoek, including the development of antibiotics against bacteria and vaccines against viruses including SARS-CoV-2.</p> <p>But it was Leeuwenhoek who first opened people’s eyes to life’s vast microscopic realm, a discovery that continues to transform the world.</p> <p><img alt="richard gunderman" data-entity-type="file" data-entity-uuid="bd77d23b-60b5-498c-b603-0d41c6c5c70a" src="/files/inline-images/richard-gunderman.png" /></p> <p>By <a href="https://medicine.iu.edu/faculty/6855/gunderman-richard">Richard Gunderman</a>, Chancellor's Professor of Medicine, Liberal Arts, and Philanthropy, Indiana University. This article is republished from <a href="https://theconversation.com">The Conversation</a> under a Creative Commons license. Read the <a href="https://theconversation.com/the-17th-century-cloth-merchant-who-discovered-the-vast-realm-of-tiny-microbes-an-appreciation-of-antonie-van-leeuwenhoek-158177">original article</a>.</p> <p> </p></div> <span><a title="View user profile." href="/author/sb-admin" lang="" about="/author/sb-admin" typeof="schema:Person" property="schema:name" datatype="">sb admin</a></span> <span>Tue, 04/06/2021 - 10:49</span> <div class="field field--name-field-blog-categories field--type-entity-reference field--label-inline"> <div class="field--label">Categories</div> <div class="field--items"> <div class="field--item"><a href="/channel/life-sciences" hreflang="en">Life Sciences</a></div> </div> </div> Tue, 06 Apr 2021 14:49:13 +0000 sb admin 151456 at https://scienceblogs.com The Increase in Infant Milk Formulas and Why It Matters https://scienceblogs.com/sb-admin/2020/12/07/increase-infant-milk-formulas-and-why-it-matters-151455 <span>The Increase in Infant Milk Formulas and Why It Matters</span> <div class="field field--name-body field--type-text-with-summary field--label-hidden field--item"><p><a href="https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(16)00210-5/fulltext">Breastfeeding</a> can play an especially important role in early-life nutrition. It can <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6486667/">benefit</a> children’s future school performance and economic prospects in later life, as well as the mother’s health.</p> <p>Health authorities across the world endorse the World Health Organization’s (WHO) <a href="https://www.who.int/health-topics/breastfeeding#tab=tab_2">recommendation</a> that newborns should where possible exclusively breastfeed from the first hour of life until six months of age, and thereafter receive safe and nutritious foods with continued breastfeeding up to two years of age or beyond.</p> <p>Despite this, our <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/mcn.13097">recent study</a> shows that global commercial milk formula sales are booming. Between 2005 and 2019, world milk formula sales more than doubled from 3.5kg to 7.4kg per child. Total sales grew from 1 million tonnes to 2.1 million tonnes.</p> <p>This growth in sales was seen in all types of formula, including “standard” formula for infants (0-6 months), “follow-up” formula (7-12 months), toddler milks (13-36 months), and so-called “specialised” formulas. So more children from a wider range of age groups are consuming formula.</p> <p>Rapid growth <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/mcn.13097">has occurred</a> in many highly-populated countries, including the Middle East, north Africa, eastern Europe, central Asia, and parts of Latin America. The most remarkable growth has been in east and south-east Asia. China, in particular, accounted for only 14% of global formula sales in 2005 – but now accounts for 33% of all sales.</p> <p>In south Asia and west and central Africa, the amount sold to each customer remains low and show no signs of growth. In Europe and North America, although per customer sales volumes remain high, they plateaued or slightly decreased between 2005-2019.</p> <p><img alt="Infant formula sare booming" data-entity-type="file" data-entity-uuid="56a1e646-83ab-4157-92be-1136ed75b22a" src="/files/inline-images/infant%20formula.jpg" /></p> <p>Infant formula sales have doubled between 2005 and 2019. <span><a href="https://www.shutterstock.com/image-photo/preparation-mixture-baby-feeding-on-wooden-554077681">279photo Studio/ Shutterstock</a></span></p> <h2><a href="https://www.shutterstock.com/image-photo/preparation-mixture-baby-feeding-on-wooden-554077681">Behind the sales ‘boom’</a></h2> <p><a href="https://www.shutterstock.com/image-photo/preparation-mixture-baby-feeding-on-wooden-554077681">There are </a><a href="https://www.who.int/nutrition/publications/infantfeeding/WHO_NMH_NHD_09.01/en/">medical reasons</a> for using safe and adequate breastmilk substitutes. And some women find continuing breastfeeding difficult depending on their circumstances, and may use formula as an alternative or complement to breastfeeding. <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/mcn.13097">Our study</a> also shows decisions and practices around formula use can be strongly shaped by wider societal forces, such as commercial marketing, rather than individual choice.</p> <p>It’s known that milk formula sales increase as countries become richer and more urbanised, and as more mothers enter into formal employment. Asia’s formula sales boom may be partly explained by millions of women entering the paid workforce, especially in the region’s vast manufacturing zones.</p> <p>Millions of women worldwide also lack adequate <a href="https://www.who.int/bulletin/volumes/98/6/19-229898/en/">paid maternity leave and social protection</a>. This means the decision to formula feed may only be done out of necessity, to avoid losing employment and income. We also know that many hospitals and healthcare settings aren’t equipped to help women establish breastfeeding, with few maternal and newborn care facilities worldwide meeting <a href="https://www.who.int/nutrition/publications/infantfeeding/bfhi-implementation/en/">standards</a> of care for breastfeeding mothers and newborns.</p> <p>Commercial factors are also important. Just five companies control 57% of the global formula milk industry, worth US$56.6 billion (£42.5 billion) The industry spends <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/mcn.13097">an estimated US$5 billion on marketing every year</a>, which <a href="https://onlinelibrary.wiley.com/doi/full/10.1111/mcn.12962">powerfully shapes social norms</a> about <a href="https://pubmed.ncbi.nlm.nih.gov/26314734/">feeding babies and children</a>.</p> <p>Marketing messages can portray formula as modern, scientific and comparable or superior to breastmilk. The growth of social media enables companies to <a href="https://globalizationandhealth.biomedcentral.com/articles/10.1186/s12992-020-00597-w#:%7E:text=Formula%20marketing%2C%20as%20for%20other,a%20brand%20and%20generic%20level.">target mothers</a> with personalised product offerings and ads.</p> <p>Hospitals are a key marketing channel, too. Companies often engage health professionals to promote formula feeding. In many countries, health professionals are directly compensated to promote formula. But more commonly, companies influence health professionals indirectly by <a href="https://pubmed.ncbi.nlm.nih.gov/31401600/">sponsoring</a> their associations, conferences and education.</p> <p><img alt="A grocery store aisle full of baby and toddler formula products." src="https://images.theconversation.com/files/369278/original/file-20201113-23-cn8j5l.jpg?ixlib=rb-1.1.0&amp;q=45&amp;auto=format&amp;w=754&amp;fit=clip" /></p> <p><span>Companies cross-promote products by using the same packaging.</span> <span><a href="https://www.shutterstock.com/image-photo/toronto-canada-november-22-2014-baby-233666974">ValeStock/ Shutterstock</a></span></p> <p>Companies also <a href="https://www.who.int/nutrition/publications/infantfeeding/information-note-cross-promotion-infant-formula/en/#:%7E:text=In%20summary%2C%20the%20now%20common,to%20breastfeeding%20and%20infant%20health.&amp;text=As%20a%20result%2C%20young%20infants,cannot%20meet%20their%20nutritional%20needs.">cross-promote</a> their entire product range of follow-up and toddler milks by using packing and labelling that resembles standard infant formula. This allows companies to get around the stricter prohibitions on infant formula marketing.</p> <p>Marketing regulations are also important. The fact that formula sales are booming in China but have flat-lined at low levels in India partly reflects contrasting regulatory environments – with regulations on marketing being stricter and more comprehensive in India.</p> <p>Despite <a href="https://www.unicef.org.uk/babyfriendly/baby-friendly-resources/international-code-marketing-breastmilk-substitutes-resources/the-code/">an international code</a> to stop <a href="https://www.who.int/nutrition/publications/infantfeeding/breastmilk-substitutes-FAQ2017/en/">aggressive and inappropriate marketing</a> of breast-milk substitutes, most governments haven’t fully incorporated it <a href="https://www.who.int/publications/i/item/9789240006010">into law</a>. And even when laws exist, marketing violations by formula companies often go unpunished. The formula industry has also been able to lobby against any strengthening of regulation, partly by promoting their own – much weaker – corporate policies on marketing.</p> <h2>Health concerns</h2> <p>Breastmilk and breastfeeding where it is possible has numerous advantages over formula and bottle feeding – which is why the growth of formula sales is concerning.</p> <p>Breastfeeding has been shown to reduce the likelihood of children developing infections, and reduces a child’s risk of <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6735804/#:%7E:text=Globally%2C%20595%20379%20childhood%20deaths,type%20II%20diabetes%20each%20year">developing chronic disease like obesity and diabetes</a> later in life. Breastfeeding is also associated with lower risk of developing <a href="https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(15)01024-7/fulltext">breast and cervical cancer, or diabetes</a> among mothers.</p> <p>Rising consumption of formula milk by toddlers and young children is also a worry, as these products are often <a href="https://theconversation.com/the-rise-of-ultra-processed-foods-and-why-theyre-really-bad-for-our-health-140537#:%7E:text=We%20found%20that%20more%20ultra,%2C%20salt%20and%20trans%2Dfats.">ultra-processed</a>, expensive, loaded with sugar and can introduce <a href="https://www.vichealth.vic.gov.au/media-and-resources/media-releases/high-sugar-toddler-milks-overpriced-harmful">poor dietary habits</a>. Their increased use could further contribute to increases of overweight and obese children globally.</p> <p>Formula isn’t a sterile product and can be dangerous when prepared in unhygienic conditions, or when over-diluted or over-concentrated. It lacks the immune-boosting and other important elements of breastmilk, further increasing the risk of malnutrition and infectious illness. As a result, universal breastfeeding in place of formula use could prevent an estimated <a href="https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(15)01024-7/fulltext">823,000 child deaths every year</a> (mainly in low- and middle-income countries), including 595,000 deaths from diarrhoea and pneumonia, and an estimated 20,000 maternal deaths from breast cancer (mainly in high income countries).</p> <p>The global surge in formula sales is clearly a problem for global health. Given the power of the corporate milk formula industry to influence behaviour and understanding, more needs to be done to ensure that all mothers and children are protected from inappropriate promotion, and that they are enabled to breastfeed as long as they want to. This means <a href="https://www.who.int/nutrition/netcode/en/">strengthening laws</a> that ban harmful marketing practices, expanding access to paid maternity leave, and ensuring that all <a href="https://www.who.int/nutrition/publications/guidelines/breastfeeding-facilities-maternity-newborn/en/">healthcare facilities</a> meet global standards.<img alt="The Conversation" height="1" src="https://counter.theconversation.com/content/149681/count.gif?distributor=republish-lightbox-basic" width="1" /></p> <p><span><a href="https://theconversation.com/profiles/david-mccoy-265876">David McCoy</a>, Professor of Global Public Health, <em><a href="https://theconversation.com/institutions/queen-mary-university-of-london-1745">Queen Mary University of London</a></em>; <a href="https://theconversation.com/profiles/julie-p-smith-145494">Julie P. Smith</a>, Honorary Associate Professor, <em><a href="https://theconversation.com/institutions/australian-national-university-877">Australian National University</a></em>, and <a href="https://theconversation.com/profiles/phillip-baker-8620">Phillip Baker</a>, Research Fellow, Institute for Physical Activity and Nutrition, Deakin University, <em><a href="https://theconversation.com/institutions/deakin-university-757">Deakin University</a></em></span></p> <p>This article is republished from <a href="https://theconversation.com">The Conversation</a> under a Creative Commons license. Read the <a href="https://theconversation.com/the-rise-of-commercial-milk-formulas-and-why-it-matters-for-the-worlds-women-and-children-149681">original article</a>.</p></div> <span><a title="View user profile." href="/author/sb-admin" lang="" about="/author/sb-admin" typeof="schema:Person" property="schema:name" datatype="">sb admin</a></span> <span>Mon, 12/07/2020 - 18:21</span> <div class="field field--name-field-blog-categories field--type-entity-reference field--label-inline"> <div class="field--label">Categories</div> <div class="field--items"> <div class="field--item"><a href="/channel/social-sciences" hreflang="en">Social Sciences</a></div> </div> </div> Mon, 07 Dec 2020 23:21:44 +0000 sb admin 151455 at https://scienceblogs.com Greenland Could Lose Ice Faster Than Any Century Since The Last Ice Age Ended https://scienceblogs.com/sb-admin/2020/09/30/greenland-could-lose-ice-faster-any-century-last-ice-age-ended-151454 <span>Greenland Could Lose Ice Faster Than Any Century Since The Last Ice Age Ended</span> <div class="field field--name-body field--type-text-with-summary field--label-hidden field--item"><p>A new estimate using sheet modeling finds that Greenland's rate of <a href="https://www.nature.com/articles/s41586-020-2742-6">ice loss this century could outpace that of any century over the past 12,000 years</a>, when the last Ice Age ended.</p> <p>Scientists used reconstructions of ancient climate to drive the model, and validated the model against real-world measurements of the ice sheet's contemporary and ancient size.</p> <p>The study brought together climate modelers, ice core scientists, remote sensing experts and paleoclimate researchers. The team used an ice sheet model to simulate changes to the southwestern sector of the Greenland Ice Sheet, starting from the beginning of the Holocene epoch 12,000 years ago and extending forward 80 years to 2100. Data came from ice cores to create maps of temperatures and precipitation in the study region that were used to drive the ice sheet model simulations up to the year 1850 while other published climate data were used to drive the simulations after that date.</p> <figure role="group"><img alt="Infographic describing the study's findings. Image: Bob Wilder / University at Buffalo" data-entity-type="file" data-entity-uuid="17c5924d-9b90-40e6-bfd0-47cde566b673" src="/files/inline-images/Greenland%20is%20on%20track%20to%20lose%20ice.jpg" width="700" /><figcaption>Infographic describing the study's findings. Image: Bob Wilder / University at Buffalo</figcaption></figure><p>Scientists tested the model's accuracy by comparing results of the model's simulations to historical measurements. The modeled results matched up well with data tied to actual measurements of the ice sheet made by satellites and aerial surveys in recent decades, and with field work identifying the ice sheet's ancient boundaries. </p> <p>"We built an extremely detailed geologic history of how the margin of the southwestern Greenland Ice Sheet moved through time by measuring beryllium-10 in boulders that sit on moraines," <a href="https://www.sciencecodex.com/study-greenland-track-lose-ice-faster-any-century-over-12000-years-657706">says co-author Nicolás Young</a>, PhD, associate research professor at LDEO. "Moraines are large piles of debris that you can find on the landscape that mark the former edge of an ice sheet or glacier. A beryllium-10 measurement tells you how long that boulder and moraine have been sitting there, and therefore tells you when the ice sheet was at that exact spot and deposited that boulder. Amazingly, the model reproduced the geologic reconstruction really well. This gave us confidence that the ice sheet model was performing well and giving us meaningful results. You can model anything you want and your model will always spit out an answer, but we need some way to determine if the model is doing a good job."</p> <p>Though the project focused on southwestern Greenland, research shows that changes in the rates of ice loss there tend to correspond tightly with changes across the entire ice sheet. </p> <p> </p></div> <span><a title="View user profile." href="/author/sb-admin" lang="" about="/author/sb-admin" typeof="schema:Person" property="schema:name" datatype="">sb admin</a></span> <span>Wed, 09/30/2020 - 14:38</span> <div class="field field--name-field-blog-categories field--type-entity-reference field--label-inline"> <div class="field--label">Categories</div> <div class="field--items"> <div class="field--item"><a href="/channel/physical-sciences" hreflang="en">Physical Sciences</a></div> </div> </div> Wed, 30 Sep 2020 18:38:02 +0000 sb admin 151454 at https://scienceblogs.com Fork-Tailed Flycatchers Make Sounds With Their Feathers in Different Accents https://scienceblogs.com/sb-admin/2020/09/24/fork-tailed-flycatchers-make-sounds-their-feathers-different-accents-151453 <span>Fork-Tailed Flycatchers Make Sounds With Their Feathers in Different Accents</span> <div class="field field--name-body field--type-text-with-summary field--label-hidden field--item"><p>(Inside Science) -- The fork-tailed flycatcher whistles with its wings in two different accents, potentially more evidence this bird is splitting into two species, a new study finds.</p> <p>Birds are known for the songs they can sing, but dozens of species also use their feathers to generate sounds. For instance, peacocks can rattle their quills together, and <a href="https://www.discovermagazine.com/planet-earth/pigeons-sound-the-alarm-with-whistling-feathers">the crested pigeon's wings whistle when they fly</a>.</p> <p>In the new study, researchers investigated fork-tailed flycatchers -- 1-ounce birds found throughout the Americas that resemble black-and-gray swallows. The males sport foot-long scissor-shaped tails as ornaments to help attract mates, and they also spread these giant feathers to help turn sharply while hunting by using the plumes as air brakes, said study lead author Valentina Gómez-Bahamón, an evolutionary biologist at the Field Museum in Chicago.</p> <p>When these birds fly -- sometimes as fast as 65 miles per hour -- they produce a high-pitched trill. Males often fly quickly when they fight each other during mating season, Gómez-Bahamón noted. The birds also fly quickly when fighting off intruders near their nests.</p> <p>The scientists studied two known subspecies of fork-tailed flycatchers: a migratory one that breeds in the southern part of South America but spends winter closer to the equator, and a nonmigratory one that spends the whole year in the northern part of the continent.</p> <p>The scientists first captured the birds with "mist nets" -- fine webbing stretched between two poles like a volleyball net -- and recorded audio and video of them as they flew away after they were released. The researchers also set up a taxidermy hawk in a field with a hidden camera, and when the fork-tailed flycatchers swooped in to attack, the researchers recorded how the flycatchers’ feathers moved and what sounds they made. The whole project took three years.</p> <p>"Recording a fast-flying fighting bird is really hard," Gómez-Bahamón said. "It took many attempts."</p> <p>The audio and video footage, as well as experiments with fork-tailed flycatcher plumes in a wind tunnel, revealed the birds create these trills with fluttering feathers. Airflow causes these plumes to vibrate with short repetitive whistles, much like the sounds <a href="https://lifestyle.howstuffworks.com/crafts/nature-crafts/easy-nature-activities-for-kids4.htm">one can whistle using a blade of grass</a>.</p> <p>Gómez-Bahamón and her colleagues discovered the migratory subspecies made higher-pitched trills with their feathers than their nonmigratory cousins.</p> <p>The migrating males possess wing feathers with skinnier tips than those of their homebody brethren. These may have evolved to make it easier to fly longer distances. The researchers suggested a group of migratory fork-tailed flycatchers ceased to be migratory, and as their wing feathers thickened because they no longer made long journeys, they ended up sounding different from those of their migratory relatives.</p> <p>"This is super-challenging work -- these birds are really aerial, and they're not tame," said evolutionary ornithologist Richard Prum at Yale University, who did not take part in this research. "I was amazed at the detail of the analysis they were capable of doing."</p> <p>Aside from escapes and fights, males of both subspecies trill with their wings in the early morning when it is still dark, likely as displays to females, Gómez-Bahamón said. The birds sing songs, are quiet for a moment, and then perform a short flight where one can hear the fluttering.</p> <p>Since wing fluttering may help the birds communicate during mating season, Gómez-Bahamón and her colleagues suggest the feather “accents” they found may help further drive the subspecies apart. Eventually, the two types of flycatchers may evolve into fully separate species that cannot interbreed with one another. "Differences in migratory behavior can cascade to other behavioral traits," Gómez-Bahamón said.</p> <p>Future research will investigate whether related species display similar behavior. The scientists will also explore whether female fork-tailed flycatchers prefer sounds from males of their subspecies, Gómez-Bahamón said. Ornithologist Juan Ignacio Areta at the Institute of Bio and Geosciences of Northwest Argentina, who did not participate in this study, wonders how preventing the birds from making feather trills might influence mate choice. "Answering these exciting questions is difficult, and requires a lot of carefully designed field experiments," he said.</p> <p>The scientists detailed <a href="https://doi.org/10.1093/icb/icaa115">their findings</a> Sept. 22 in the journal <em>Integrative and Comparative Biology</em>.</p> <p>Charles Q. Choi is a science reporter who has written for Scientific American, The New York Times, Wired, Science, Nature, and National Geographic News, among others. Reprinted with permission from <a href="https://www.insidescience.org/news/long-tailed-bird-makes-sounds-its-feathers-different-accents">Inside Science</a>, an editorially independent news product of the American Institute of Physics, a nonprofit organization dedicated to advancing, promoting and serving the physical sciences.</p></div> <span><a title="View user profile." href="/author/sb-admin" lang="" about="/author/sb-admin" typeof="schema:Person" property="schema:name" datatype="">sb admin</a></span> <span>Thu, 09/24/2020 - 10:46</span> <div class="field field--name-field-blog-categories field--type-entity-reference field--label-inline"> <div class="field--label">Categories</div> <div class="field--items"> <div class="field--item"><a href="/channel/education" hreflang="en">Education</a></div> </div> </div> Thu, 24 Sep 2020 14:46:18 +0000 sb admin 151453 at https://scienceblogs.com