<p>Today's <strong>Image of the Day</strong> from the European Space Agency features the star-forming region NGC 604. The nebula is located 2.73 million light-years away from Earth in the Triangulum Galaxy (M33). </p>



<p>By studying regions like NGC 604, astronomers can gain insights into the complex interactions between stars and the interstellar medium, as well as the conditions that lead to the birth of stars. </p>



<p>This, in turn, helps us understand the evolution of <a href="https://www.earth.com/news/galaxies-like-our-own-milky-way-are-not-unique/" target="_blank" rel="noreferrer noopener">galaxies</a> and the universe as a whole.</p>



<h2 class="wp-block-heading" id="h-massive-stars-of-ngc-604">Massive stars of NGC 604</h2>



<p>"Sheltered among NGC 604’s dusty envelopes of gas are more than 200 of the hottest, most massive kinds of stars, all in the early stages of their lives," said <a href="https://www.esa.int/" target="_blank" rel="noreferrer noopener">ESA</a>.</p>



<p>"These types of stars are known as B-types and O-types, the latter of which can be more than 100 times the mass of our own Sun. It’s quite rare to find this concentration of them in the nearby universe. In fact, there’s no similar region within our own Milky Way galaxy."</p>



<p>According to ESA, this concentration of massive stars, combined with its relatively close distance, means that NGC 604 gives astronomers an opportunity to study these objects at a fascinating time early in their life.</p>



<h2 class="wp-block-heading" id="h-gigantic-region-of-ionized-hydrogen">Gigantic region of ionized hydrogen</h2>



<p>NGC 604 is one of the largest known regions of ionized hydrogen, also known as an H II region. This nebula is significantly larger than the Orion Nebula, which is one of the most well-known H II regions in our own <a href="https://www.earth.com/news/large-amount-of-dark-matter-may-be-missing-from-the-milky-way/" target="_blank" rel="noreferrer noopener">Milky Way galaxy</a>.&nbsp;</p>



<p>NGC 604 spans about 1,500 light-years across, making it one of the largest H II regions in the Local Group of galaxies. This group includes the Milky Way, the Andromeda Galaxy, and about 54 other smaller galaxies.&nbsp;</p>



<h2 class="wp-block-heading" id="h-ngc-604-starburst-phenomenon">NGC 604 starburst phenomenon </h2>



<p>Within NGC 604, there are hundreds of young, hot, massive <a href="https://www.earth.com/news/stars-at-the-edge-of-our-milky-way-galaxy-travel-more-slowly/" target="_blank" rel="noreferrer noopener">stars</a>. These stars have ionized the surrounding gas, causing it to glow and creating the nebula. </p>



<p>The region is a prime example of a starburst phenomenon, where stars form at a much higher rate than in typical galactic conditions.</p>



<p>“The bright orange streaks in this image signify the presence of carbon-based molecules known as polycyclic aromatic hydrocarbons, or PAHs," explained ESA.</p>



<p>"As you travel further from the immediate cavities of dust where the star is forming, the deeper red signifies molecular hydrogen. This cooler gas is a prime environment for star formation. Ionized hydrogen from ultraviolet radiation appears as a white and blue ghostly glow."</p>



<h2 class="wp-block-heading" id="h-more-about-star-formation">More about star formation </h2>



<p>Star formation is crucial for the evolution of galaxies and the synthesis of heavy elements. In the cores of stars, elements heavier than helium are created.</p>



<p>The elements are spread throughout the <a href="https://www.earth.com/news/ancient-stars-shakti-shiva-shaped-milky-way-galaxy/" target="_blank" rel="noreferrer noopener">galaxy</a> when stars reach the end of their lives and expel their material - either gently through winds or violently via supernova explosions. </p>



<p>This enriching process allows for the formation of new stars and planets, and ultimately, the potential for life.</p>



<h3 class="wp-block-heading">Cloud collapse</h3>



<p>The process begins when part of a molecular cloud becomes unstable and starts to collapse under its own gravity. This can be triggered by events like shock waves from nearby <a href="https://www.earth.com/news/supernova-explosions-could-damage-distant-planets/" target="_blank" rel="noreferrer noopener">supernovae</a>, galactic collisions, or the influence of other massive stars.</p>



<h3 class="wp-block-heading">Formation of a protostar</h3>



<p>As the cloud collapses, it fragments into smaller clumps. Each clump will eventually form one or more stars. </p>



<p>The material within these clumps continues to fall inward, heating up as it does so, eventually forming a warm core called a protostar. At this stage, the protostar is not yet hot enough for nuclear fusion (the process that powers stars) to occur.</p>



<h3 class="wp-block-heading">Accretion disk</h3>



<p>Around the protostar, material from the surrounding cloud continues to fall inward, forming a rotating disk. This material slowly accretes onto the protostar, increasing its mass.</p>



<h3 class="wp-block-heading">Nuclear fusion begins</h3>



<p>Once the core of the protostar reaches a high enough temperature and pressure, hydrogen atoms begin to fuse into helium, releasing energy in the process. This marks the transition from a protostar to a main sequence star, like our sun.</p>



<h3 class="wp-block-heading">Main sequence and beyond</h3>



<p>The star will spend the majority of its life in the main sequence stage, where it balances the gravitational forces trying to collapse it and the outward pressure from nuclear fusion. </p>



<p>Eventually, the star will exhaust its hydrogen fuel. Its subsequent evolution will depend on its initial mass, leading to various end stages such as red giants, supernovae, neutron stars, or black holes.</p>



<p>Image Credit: NASA/ESA/CSA James Webb Space Telescope</p>



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Young, massive stars in the Triangulum Galaxy

Today's Image of the Day from the European Space Agency...

<p>Today's <strong>Image of the Day</strong> from the European Space Agency features Abell S1063, a massive galaxy cluster located about 4.5 billion light-years from Earth. The galaxy cluster was captured by the Webb telescope in stunning detail.</p>



<p>According to <a href="https://www.esa.int/ESA_Multimedia/Images/2025/05/Webb_glimpses_the_distant_past" target="_blank" rel="noreferrer noopener">ESA</a>, the image is what’s known as a deep field - a long exposure of a single area of the sky, collecting as much light as possible to draw out the most faint and distant galaxies that don’t appear in ordinary images.&nbsp;</p>



<h2 class="wp-block-heading" id="h-galaxies-of-the-early-universe">Galaxies of the early universe </h2>



<p>Composed of nine separate snapshots taken at different near-infrared wavelengths over roughly 120 hours, this image represents Webb’s most detailed and deepest view of a single target so far.&nbsp;</p>



<p>Thanks to the gravitational lensing effect of Abell S1063, astronomers can peer deeper into the past than ever before - possibly viewing some of the universe’s very <a href="https://www.earth.com/news/ancient-galaxies-formed-from-the-earliest-elements-in-the-universe/" target="_blank" rel="noreferrer noopener">first galaxies</a>.</p>



<p>“The eye is first drawn, in this new NASA/ESA/CSA James Webb Space Telescope Picture of the Month, to the central mega-monster that is galaxy cluster Abell S1063. This behemoth collection of galaxies, lying 4.5 billion light-years from Earth in the constellation Grus (the Crane), dominates the scene,” noted ESA.</p>



<p>“Looking more closely, this dense collection of heavy galaxies is surrounded by glowing streaks of light, and these warped arcs are the true object of scientists’ interest: faint galaxies from the universe’s distant past.”</p>



<h2 class="wp-block-heading" id="h-what-is-a-galaxy-cluster">What is a galaxy cluster?</h2>



<p>Galaxy clusters are the largest known gravitationally bound systems and include not just galaxies, but also vast amounts of hot, X-ray-emitting gas and <a href="https://www.earth.com/news/the-true-nature-of-dark-matter-may-be-revealed-in-a-supernova/" target="_blank" rel="noreferrer noopener">dark matter</a>.&nbsp;</p>



<p>The galaxies within a cluster move through this hot intracluster medium, and their interactions can lead to phenomena like galaxy mergers or the stripping of gas from galaxies.&nbsp;</p>



<p>Galaxy clusters are important for studying the large-scale structure of the universe, the behavior of dark matter, and the evolution of galaxies over cosmic time.</p>



<h2 class="wp-block-heading" id="h-hundreds-of-galaxies-bound-together-nbsp">Hundreds of galaxies bound together&nbsp;</h2>



<p>As one of the most densely populated clusters known, Abell S1063 contains hundreds of galaxies bound together by gravity.&nbsp;</p>



<p>Its immense mass makes it an excellent example of a gravitational lens - a cosmic phenomenon where the cluster’s gravity bends and magnifies the light from galaxies far behind it.&nbsp;</p>



<p>This effect allows astronomers to observe incredibly faint and distant <a href="https://www.earth.com/news/milky-way-like-galaxies-were-present-in-the-early-universe/" target="_blank" rel="noreferrer noopener">galaxies</a> that would otherwise be beyond our detection limits.</p>



<h2 class="wp-block-heading" id="h-studying-galaxy-evolution">Studying galaxy evolution</h2>



<p>The cluster has been the focus of several major observational campaigns. It was prominently featured in the Hubble Space Telescope’s Frontier Fields program, which used its gravitational lensing power to study the early universe.&nbsp;</p>



<p>“The new imagery from Webb’s Near-Infrared Camera (NIRCam) takes this quest even further back in time,” said ESA.</p>



<p>“This image showcases an incredible forest of lensing arcs around Abell S1063, which reveal distorted background galaxies at a range of cosmic distances, along with a multitude of faint galaxies and previously unseen features.”</p>



<p>These observations are helping scientists probe the Cosmic Dawn era - the period shortly after the Big Bang.</p>



<h2 class="wp-block-heading" id="h-exploring-the-cosmic-dawn-nbsp">Exploring the Cosmic Dawn&nbsp;</h2>



<p>The Cosmic Dawn refers to a time in the history of the universe when the first stars and galaxies began to form and shine. This pivotal era occurred roughly between 100 million and 1 billion years after the Big Bang.&nbsp;</p>



<p>During the Dark Ages, the <a href="https://www.earth.com/news/fastest-feeding-black-hole-found-in-the-early-universe/" target="_blank" rel="noreferrer noopener">universe</a> had cooled enough for neutral hydrogen to form, but no luminous objects yet existed to light it up.&nbsp;</p>



<p>The birth of the first stars - often massive and short-lived - marked the beginning of the Cosmic Dawn. These stars emitted intense ultraviolet radiation, which gradually ionized the surrounding hydrogen gas in a process known as reionization.&nbsp;</p>



<p>This transformed the universe from a cold, opaque environment into one that was transparent to light, enabling the large-scale structure of the cosmos to take shape.</p>



<h2 class="wp-block-heading" id="h-the-constellation-grus">The constellation Grus</h2>



<p>Grus is a <a href="https://www.earth.com/news/super-jupiter-discovered-in-the-great-bear-constellation/" target="_blank" rel="noreferrer noopener">constellation</a> in the southern sky, its name derived from the Latin word for "crane," a type of large, graceful bird.&nbsp;</p>



<p>It was introduced in the late 16th century by the Dutch navigators Pieter Dirkszoon Keyser and Frederick de Houtman, during an era of celestial charting tied to European exploration of the southern hemisphere.&nbsp;</p>



<p>Grus is part of a group of constellations known as the "Southern Birds," which also includes Phoenix, Tucana, and Pavo.</p>



<p>This constellation lies near the celestial south pole and is best seen from the Southern Hemisphere during the months of August through October.&nbsp;</p>



<p>Image Credit: ESA/Webb, NASA &amp; CSA, H. Atek, M. Zamani</p>



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Hundreds of galaxies illuminate the early universe 

<p>Today's <strong>Image of the Day</strong> from the European Space Agency features a Copernicus map of scorching summer temperatures across southern Europe.</p>



<p>“A powerful heatwave has been gripping large parts of southern Europe and North Africa, pushing air temperatures beyond seasonal norms and triggering widespread health and wildfire alerts. Among the hardest-hit countries are Spain, France, Italy, Greece, Cyprus, and Algeria,” said <a href="https://www.esa.int/ESA_Multimedia/Images/2025/07/Southern_Europe_s_land_and_sea_sizzles">ESA</a>.</p>



<p>“This image, a mosaic from five overlapping orbital passes in the morning of 29 June 2025, was captured by the <a href="https://www.esa.int/Applications/Observing_the_Earth/Copernicus/Sentinel-3">Copernicus Sentinel-3</a> mission’s Sea and Land Surface Temperature Radiometer.”&nbsp;</p>



<h2 class="wp-block-heading" id="h-tracking-land-surface-temperatures-nbsp">Tracking land surface temperatures&nbsp;</h2>



<p>According to ESA, the image reveals the temperature of the land surface - not air temperature.</p>



<p>Tracking land surface temperature is essential for predicting weather and climate patterns, assessing wildfire risk, helping <a href="https://www.earth.com/news/rising-temperatures-threaten-the-future-of-banana-farming/">farmers</a> plan irrigation, and informing urban design strategies to reduce heat.</p>



<p>“Unlike measurements of air temperature, this satellite instrument measures the actual thermal energy emitted from Earth’s surface, which typically registers higher than air temperatures.”</p>



<h2 class="wp-block-heading" id="h-heat-dome-over-western-europe-nbsp">Heat dome over Western Europe&nbsp;</h2>



<p>The image includes information from the Copernicus Marine Service, which shows that <a href="https://www.earth.com/news/ocean-temperatures-are-rising-faster-than-expected-and-likely-to-accelerate/">surface temperatures</a> are also hot across the Mediterranean Sea.</p>



<p>The ongoing heatwave is fueled by a high-pressure system stalled over Western Europe, known as a “heat dome.” This system traps hot, dry air beneath it, causing temperatures to rise steadily.&nbsp;</p>



<p>As it moves eastward, the dome pulls in even more hot air from North Africa, intensifying the extreme heat across the region.</p>



<h2 class="wp-block-heading" id="h-heat-dome-over-the-united-states-nbsp">Heat dome over the United States&nbsp;</h2>



<p>In June 2025, a heat dome developed over the central and eastern United States. It began forming around June 20 and persisted through the week.</p>



<p>The heat dome covered a large part of the country - from the Great Plains through the Midwest, Upper Midwest, Ohio and Tennessee River Valleys - and extended into the Mid‑Atlantic and Northeast regions.</p>



<p>More than 280 daily high-temperature records were shattered across the U.S., affecting some 130 million people under <a href="https://www.earth.com/news/extreme-heat-impacts-our-daily-routines-and-transportation/">heat warnings</a> or advisories.&nbsp;</p>



<p>Cities like New York, Baltimore, Philadelphia, Boston, Newark, Providence, and Raleigh saw triple-digit highs - some reaching more than 105 degrees.</p>



<h2 class="wp-block-heading" id="h-public-health-concerns">Public health concerns</h2>



<p>The heat dome not only caused dangerous daytime highs but also oppressive night-time warmth, with low temperatures often staying above 80 °F due to trapped heat. </p>



<p>This persistent warmth strained power grids, led to emergency declarations, and triggered significant public health concerns.</p>



<p>Infrastructure suffered too: roads buckled in Missouri and softened asphalt sank vehicles in New York City, while a Baltimore Amtrak train stalled in a tunnel from the heat. </p>



<p>Emergency measures included power reductions, heat shelters, and utility advisories in several states.</p>



<h2 class="wp-block-heading" id="h-heat-domes-and-climate-change">Heat domes and climate change</h2>



<p>Climate scientists emphasize that heat domes are fueled by anthropogenic <a href="https://www.earth.com/news/climate-change-earth-energy-imbalance-temperature-rise/">climate change</a>. These high-pressure patterns are occurring more frequently and enduring longer due to warming oceans, Arctic amplification, and altered jet stream behavior.&nbsp;</p>



<p>As global temperatures rise, the atmosphere can hold more moisture and energy, which intensifies heatwaves and makes them more persistent.&nbsp;</p>



<p>In particular, the weakened and meandering jet stream - a result of a warming Arctic - is allowing systems like heat domes to stall over regions for days or even weeks.</p>



<h2 class="wp-block-heading" id="h-adapting-to-a-hotter-future">Adapting to a hotter future</h2>



<p>Recent climate models show that events like the June 2025 heat dome (once considered rare), are becoming increasingly common.&nbsp;</p>



<p>What used to be a one-in-100-year heat event in many U.S. cities may now occur once a decade or even more often. This shift has serious implications not just for human health, but also for infrastructure, agriculture, and energy systems.&nbsp;</p>



<p>Power grids are pushed to their limits, roads and railways buckle under extreme heat, and crops suffer from both high temperatures and water stress.</p>



<p>Public health officials are especially concerned about the cumulative toll of prolonged <a href="https://www.earth.com/news/extreme-heat-is-pushing-parts-of-earth-beyond-human-survival/">extreme heat</a>. </p>



<p>Nights that remain hot offer little relief and are particularly dangerous for vulnerable populations such as the elderly, young children, and people with chronic health conditions. </p>



<p>Without sustained adaptation efforts - such as redesigning cities to reduce heat retention, expanding access to cooling centers, and modernizing energy infrastructure - the human and economic cost of extreme heat is expected to grow significantly in the coming decades.</p>



<p>Image Credit: ESA</p>



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Heat dome scorches Southern Europe 

<p>Today's <strong>Image of the Day</strong> from the European Space Agency features the Eagle Nebula, also known as Messier 16, which is located about 7,000 light-years away in the constellation Serpens.</p>



<p>The Eagle Nebula is one of the most iconic star-forming regions in our galaxy. It’s a vast cloud of gas and dust stretching roughly 70 light-years across. </p>



<h2 class="wp-block-heading" id="h-pillars-of-creation-nbsp">Pillars of Creation&nbsp;</h2>



<p>What makes it especially famous is a portion of the <a href="https://www.earth.com/news/six-rogue-worlds-discovered-inside-a-young-star-forming-nebula/">nebula</a> captured by the Hubble Space Telescope in 1995 - an area called the "Pillars of Creation."&nbsp;</p>



<p>Some of these towering columns of gas are several light-years tall. The towers resemble sculpted fingers reaching out into space. Inside these pillars, new <a href="https://www.earth.com/news/serpens-nebula-image-reveals-how-stars-are-born/">stars</a> are being born as gravity pulls material together into dense cores that eventually ignite nuclear fusion.</p>



<p>The Pillars of Creation are often cited as a poetic example of the cosmic cycle of birth and destruction - where new stars are born even as the surrounding material is slowly destroyed by radiation.</p>



<h2 class="wp-block-heading" id="h-hubble-image-of-the-eagle-nebula-nbsp">Hubble image of the Eagle Nebula&nbsp;</h2>



<p>“This towering structure of billowing gas and dark, obscuring dust might only be a small portion of the Eagle Nebula, but it is no less majestic in appearance for it,” said <a href="https://esahubble.org/images/heic2507a/">ESA</a>.</p>



<p>“The new Hubble image is part of ESA/Hubble’s 35th anniversary celebrations. The cosmic cloud shown here is made of cold hydrogen gas, like the rest of the Eagle Nebula. In such regions of space new stars are born among the collapsing clouds.”&nbsp;</p>



<p>The hot, energetic stars emit intense ultraviolet light and powerful stellar winds that erode and sculpt the surrounding gas. The result is the creation of fantastical structures - like the narrow pillar with a blossoming head featured in the new image.</p>



<h2 class="wp-block-heading" id="h-light-and-shadow-in-the-eagle-nebula">Light and shadow in the Eagle Nebula</h2>



<p>The thick material in the pillar blocks most light, appearing dark and heavy against the backdrop. However, its edges glow where light from the more distant nebula shines through.&nbsp;</p>



<p>The striking colors reflect the chemistry and physics at play: blues signal ionized oxygen, reds indicate glowing hydrogen, and orange shows where starlight has managed to pierce the dust.</p>



<h2 class="wp-block-heading" id="h-a-structure-under-siege">A structure under siege</h2>



<p>Just out of frame lie the very stars responsible for shaping this dramatic pillar. Their radiation and winds continue to batter the cloud, compressing the gas and potentially triggering the birth of even more stars within.</p>



<p>For now, the pillar holds firm, but this stability is temporary. Over time, the relentless energy from newly formed <a href="https://www.earth.com/news/fluffy-molecular-clouds-may-change-our-understanding-of-star-formation/">stars</a> will eventually erode the entire structure.</p>



<p>“While the starry pillar has withstood these forces well so far, cutting an impressive shape against the background, eventually it will be totally eroded by the multitude of new stars that form in the Eagle Nebula,” explained ESA.</p>



<h2 class="wp-block-heading" id="h-life-cycle-of-the-milky-way">Life cycle of the Milky Way</h2>



<p>The nebula’s location in the Sagittarius Arm - one of the Milky Way’s major spiral arms - places it in a zone bustling with similar star-forming regions. This highlights the role of the Eagle Nebula in shaping the structure and the future of our galaxy.</p>



<p>Studies of the Eagle Nebula have revealed that the region is rich in young, hot stars - some of which are only a few million years old. These stars are in various stages of development, providing a natural laboratory for astronomers to study stellar life cycles.&nbsp;</p>



<h2 class="wp-block-heading" id="h-evolution-of-the-eagle-nebula-nbsp">Evolution of the Eagle Nebula&nbsp;</h2>



<p>Within the Eagle Nebula, there is a variety of stellar processes occurring in close proximity. Some stars are still forming within dense clouds of gas, while others have already matured and begun to emit powerful ultraviolet radiation.&nbsp;</p>



<p>The ongoing interaction between <a href="https://www.earth.com/news/star-formation-reignited-in-the-galaxy-leo-p-after-billions-of-years/">young stars</a> and their environment drives the evolution of the nebula itself.&nbsp;</p>



<p>As newly formed stars heat and disperse the gas and dust around them, they trigger further waves of star formation - or in some cases, halt it altogether.&nbsp;</p>



<p>This feedback loop not only influences the pace of star birth in the Eagle Nebula but also contributes to the broader life cycle of matter within the <a href="https://www.earth.com/news/milky-way-collision-may-change-everything-we-know-about-our-galaxy/">Milky Way</a>, enriching the galaxy with heavier elements forged in stellar cores.</p>



<p>Image Credit: ESA/Hubble &amp; NASA, K. Noll</p>



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Eagle Nebula: Carving light from darkness

<p>Today's <strong>Image of the Day</strong> from the European Space Agency features a portion of the Rosette Nebula, captured by the Hubble Space Telescope.</p>



<p>The Rosette Nebula is a vast cloud of gas and dust located in the constellation Monoceros, also known as the Unicorn.</p>



<p>Shaped like a blooming rose in deep space, it lies about 5,200 light-years from Earth and spans roughly 100 light-years in diameter.&nbsp;</p>



<h2 class="wp-block-heading" id="h-image-of-the-rosette-nebula">Image of the Rosette Nebula </h2>



<p>“<a href="https://www.earth.com/news/35-years-of-hubble-the-telescope-that-changed-our-view-of-the-universe/" target="_blank" rel="noreferrer noopener">Hubble</a> zooms into a small portion of the nebula that is only four light-years across (the approximate distance between our Sun and the neighboring Alpha Centauri star system),” noted <a href="https://www.esa.int/ESA_Multimedia/Images" target="_blank" rel="noreferrer noopener">ESA</a>.</p>



<p>“Dark clouds of hydrogen gas laced with dust are silhouetted across the image. The clouds are being eroded and shaped by the seething radiation from the cluster of larger stars in the center of the nebula.”&nbsp;</p>



<p>“An embedded star seen at the tip of a dark cloud in the upper right portion of the image is launching jets of plasma that are crashing into the cold cloud around it. The resulting shock wave is causing a red glow. The colors come from the presence of hydrogen, oxygen, and nitrogen.”</p>



<h2 class="wp-block-heading" id="h-distinct-appearance-of-rosette">Distinct appearance of Rosette</h2>



<p>Stellar winds and ultraviolet light are gradually carving out a cavity in the nebula’s center while simultaneously triggering new waves of <a href="https://www.earth.com/news/fluffy-molecular-clouds-may-change-our-understanding-of-star-formation/" target="_blank" rel="noreferrer noopener">star formation</a> along its dense edges.&nbsp;</p>



<p>The Rosette Nebula is often studied to understand the life cycle of stars and the complex interactions between radiation and interstellar material. </p>



<p>Its intricate structure and visual appeal have made it a favorite target for both professional astronomers and astrophotographers.</p>



<h2 class="wp-block-heading" id="h-nebulae-that-are-similar-to-rosette">Nebulae that are similar to Rosette</h2>



<p>Compared to other famous nebulae, the Rosette Nebula stands out for its symmetry and floral appearance, which give it a distinct, iconic look. It's often compared to the Orion Nebula, which is much closer to Earth at about 1,300 light-years away and far brighter in the night sky. </p>



<p>The <a href="https://www.earth.com/news/orion-nebula-destroys-an-oceans-worth-of-water-every-month/" target="_blank" rel="noreferrer noopener">Orion Nebula</a> is a bustling stellar nursery visible even to the naked eye, while the Rosette requires a telescope and is more diffuse and fainter despite being larger in actual size.</p>



<p>The Eagle Nebula, home to the famous "Pillars of Creation," shares a similar process of star formation and sculpting by radiation, but the Eagle has more dramatic, finger-like structures.&nbsp;</p>



<h2 class="wp-block-heading" id="h-stellar-feedback-and-cosmic-evolution">Stellar feedback and cosmic evolution</h2>



<p>The Lagoon Nebula and the Trifid Nebula, both in the constellation Sagittarius, also resemble the Rosette in that they are active star-forming regions, but they lie in a denser part of the <a href="https://www.earth.com/news/astronomers-found-something-strange-at-core-of-milky-way-galaxy-webb-meerkat/" target="_blank" rel="noreferrer noopener">Milky Way</a> and are often surrounded by a rich starfield.</p>



<p>What makes the Rosette Nebula particularly interesting scientifically is the clear interaction between its central star cluster and the surrounding gas, offering a textbook example of how massive stars influence their environment. </p>



<p>It may not be as visually iconic as the Orion or as dynamic as the Eagle, but it's a beautiful and instructive example of stellar feedback and cosmic evolution.</p>



<h2 class="wp-block-heading" id="h-history-of-the-rosette-nebula">History of the Rosette Nebula </h2>



<p>The history of the Rosette Nebula, like many deep-sky objects, is a blend of observational discovery and increasing scientific understanding over time. </p>



<p>Although it was likely spotted by earlier astronomers, its first documented observation was in the late 17th century by John Flamsteed, the first Astronomer Royal of England.&nbsp;</p>



<p>However, the <a href="https://www.earth.com/news/six-rogue-worlds-discovered-inside-a-young-star-forming-nebula/" target="_blank" rel="noreferrer noopener">nebula</a> itself was not fully recognized as a distinct object until the advent of astrophotography and improved telescopes in the 19th and 20th centuries.</p>



<h2 class="wp-block-heading" id="h-star-clusters-of-the-enormous-cloud">Star clusters of the enormous cloud</h2>



<p>The central star cluster, NGC 2244, was cataloged separately by William Herschel in the 18th century. Over time, astronomers realized that this cluster was embedded in a much larger, complex nebular structure.&nbsp;</p>



<p>As telescope technology advanced, astronomers identified several parts of the Rosette Nebula and gave them separate designations, including NGC 2237, NGC 2238, NGC 2239, and NGC 2246 - essentially referring to different regions of the same enormous cloud.</p>



<p>Observations from space-based telescopes like Chandra (X-rays) and Spitzer (infrared) helped map the energetic processes inside the nebula, revealing how radiation and stellar winds from NGC 2244 are triggering the birth of new stars in its surrounding regions.</p>



<p>Image Credit: ESA</p>



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Rosette Nebula: A flower blooming in deep space

<p>Type 5 diabetes is no longer a footnote. On April 9, 2025 the <a href="https://idf.org/" target="_blank" rel="noreferrer noopener">International Diabetes Federation</a> confirmed that chronic undernutrition can seed a very different form of blood‑sugar trouble, giving the condition its own place in the global classification system.</p>



<p>“Malnutrition‑related diabetes has historically been vastly under‑diagnosed and poorly understood,” said Dr. Meredith Hawkins as the vote was announced. </p>



<p>Hawkins is an endocrinologist at <a href="https://einsteinmed.edu/" target="_blank" rel="noreferrer noopener">Albert Einstein College of Medicine</a> and founding director of the Global Diabetes Institute (<a href="https://einsteinmed.edu/centers/global-health/global-diabetes-institute/" target="_blank" rel="noreferrer noopener">GDI</a>).</p>



<h2 class="wp-block-heading" id="h-why-a-fifth-type-matters">Why a fifth type matters</h2>



<p>Nearly one in nine adults worldwide now lives with some form of diabetes, and more than 250 million people remain unaware of their status, according to the 11th edition of the <a href="https://idf.org/news/idf-diabetes-atlas-11th-edition/" target="_blank" rel="noreferrer noopener">IDF Diabetes Atlas</a>.</p>



<p>Most public campaigns focus on type 2 diabetes, yet an estimated 20 to 25 million lean adolescents and young adults in Asia and Africa carry the new diagnosis of type 5, a burden comparable in size to HIV infection in the same regions.</p>



<p>Unlike type 2, type 5 takes hold where food is scarce, not plentiful. That reality undercuts a long‑standing public narrative that ties <a href="https://www.earth.com/news/scientists-identify-a-cellular-switch-mitochondria-that-could-reverse-type-2-diabetes/">diabetes</a> exclusively to over‑nutrition.</p>



<p>For governments counting every healthcare dollar, a distinct label matters. Budgets follow labels, and without one, entire populations have slipped through screening and treatment programs designed for very different metabolic problems.</p>



<p>“This is about equity, science, and saving lives,” said <a href="https://idf.org/who-we-are/our-structure/board/" target="_blank" rel="noreferrer noopener">Professor Peter Schwarz</a>, president of the IDF, summing up the stakes during the Bangkok congress.&nbsp;</p>



<h2 class="wp-block-heading" id="h-early-hunger-leaves-a-lasting-mark">Early hunger leaves a lasting mark</h2>



<p>Decades of animal work show that a low‑protein diet during gestation or adolescence stunts pancreatic growth and the formation of <a href="https://pmc.ncbi.nlm.nih.gov/articles/PMC10046343/" target="_blank" rel="noreferrer noopener">beta cells</a>, the tiny factories that make insulin. </p>



<p>Human epidemiology echoes that biology, linking low birth weight and recurring childhood malnutrition to impaired glucose control later on.</p>



<p>Researchers now group type 5 under <a href="https://diabetesjournals.org/diabetes/article/69/10/2086/16081/Subtypes-of-Type-2-Diabetes-Determined-From" target="_blank" rel="noreferrer noopener">severe insulin‑deficient diabetes</a>, a label that captures the core defect: the pancreas never learned to keep up with sugar loads, even though the rest of the body remains sensitive to insulin.</p>



<p>In South India, investigators tracked adults whose body‑mass index averaged just 18.3 kg/m² yet whose blood sugar routinely soared; birth‑weight records, where available, pointed to under‑nutrition in the womb. </p>



<p>Community nutrition programs are therefore viewed not only as anti‑hunger measures but also as long‑range <a href="https://www.earth.com/news/sugary-drinks-linked-to-millions-of-diabetes-and-heart-disease-cases/">diabetes</a> prevention.</p>



<p>Public‑health economists note a secondary benefit. Feed a girl properly before and during pregnancy, and her children may avoid the same metabolic trap, breaking an expensive inter‑generational cycle of disease.</p>



<h2 class="wp-block-heading" id="h-different-metabolic-fingerprint">Different metabolic fingerprint</h2>



<p>State‑of‑the‑art euglycemic clamp <a href="https://diabetesjournals.org/care/article/45/6/1428/146920/An-Atypical-Form-of-Diabetes-Among-Individuals" target="_blank" rel="noreferrer noopener">studies</a>, published in 2022, confirmed that type 5 patients secrete dramatically less insulin than matched controls while showing normal or even heightened insulin sensitivity.</p>



<p>The same work found little <a href="https://my.clevelandclinic.org/health/diseases/24147-visceral-fat" target="_blank" rel="noreferrer noopener">visceral fat</a> and modest liver fat, a stark contrast to type 2 profiles. In practical terms, these young adults do not carry the metabolic baggage that fuels insulin resistance in obesity‑driven diabetes.</p>



<p><a href="https://www.testing.com/tests/autoantibodies/" target="_blank" rel="noreferrer noopener">Autoantibody screens</a> stay negative, ruling out the <a href="https://pmc.ncbi.nlm.nih.gov/articles/PMC5723426/" target="_blank" rel="noreferrer noopener">immune‑mediated beta‑cell destruction</a> that defines type 1 diabetes. </p>



<p>The numbers therefore line up: glucose levels look dangerous, <a href="https://medlineplus.gov/lab-tests/c-peptide-test/" target="_blank" rel="noreferrer noopener">C‑peptide</a> looks scant, but inflammatory markers typical of autoimmunity are absent.</p>



<p>Because the pancreas is small, many experts suspect that oral drugs that nudge the remaining beta cells may help more than high‑dose insulin injections, a strategy that could lower costs and reduce dangerous hypoglycemia in food‑insecure settings.</p>



<h2 class="wp-block-heading" id="h-diabetes-type-causes-clinical-confusion">Diabetes type causes clinical confusion </h2>



<p>“Doctors are still unsure how to treat these patients, who often don’t live for more than a year after diagnosis,” Dr. Hawkins warned. </p>



<p>Younger clinicians, trained on the obesity paradigm, may reach for large insulin doses that push already fragile patients into <a href="https://karger.com/gel/article-abstract/86/4/535/358345/The-Etiologic-Factors-in-the-Causation-of?redirectedFrom=PDF" target="_blank" rel="noreferrer noopener">ulcerating hypoglycemia</a>.</p>



<p>Misclassification also skews surveillance data. When a thin teenager in rural Uganda shows up with elevated glucose but no <a href="https://www.earth.com/news/keto-diet-promotes-fat-loss-but-potentially-wrecks-your-health/">ketosis</a>, the chart often reads “type 1,” obscuring the true epidemiology and directing precious insulin supplies away from those who need them.</p>



<p>A 2025 commentary in the <a href="https://journals.lww.com/bjem/pages/currenttoc.aspx" target="_blank" rel="noreferrer noopener"><em>Bangladesh Journal of Endocrinology</em></a> emphasized the threat: standard insulin regimens carry “potentially fatal consequences” for type 5 patients who are mis‑typed as type 1, because even small dosing errors provoke sharp glucose crashes.</p>



<p>Simple screening cues can help. A BMI below 19 kg/m² in the absence of autoantibodies should prompt consideration of type 5, especially when the history includes prolonged childhood hunger.</p>



<h2 class="wp-block-heading" id="h-steps-for-care-of-diabetes-type-5">Steps for care of diabetes type 5</h2>



<p>Two weeks after the Bangkok vote, the <a href="https://idf.org/news/new-type-5-diabetes-working-group/" target="_blank" rel="noreferrer noopener">IDF</a> launched a dedicated working group to write diagnostic criteria, compile treatment algorithms, and build an international patient registry by 2027.</p>



<p>The panel, co‑chaired by Hawkins and <a href="https://www.cmcendovellore.org/nihal-thomas-php/" target="_blank" rel="noreferrer noopener">Dr. Nihal Thoma</a>s of <a href="https://www.cmch-vellore.edu/" target="_blank" rel="noreferrer noopener">Christian Medical College</a> in Vellore, India, will test low‑dose insulin, <a href="https://www.ncbi.nlm.nih.gov/books/NBK513225/" target="_blank" rel="noreferrer noopener">sulfonylureas</a>, and structured nutrition programs in multi‑site trials. Results could reshape essential‑medicine lists in low‑income countries.</p>



<p>Public‑health agencies are already modeling the economic impact. Analysts predict that shifting even half of misdiagnosed cases from <a href="https://www.earth.com/news/scientists-identify-a-cellular-switch-mitochondria-that-could-reverse-type-2-diabetes/">insulin</a> vials to oral drugs could save tens of millions of dollars each year, funds that might be redirected to <a href="https://www.earth.com/news/fathers-have-a-surprising-influence-on-their-babys-birth-weight/">maternal nutrition</a>.</p>



<p>Advocates also press for the inclusion of pancreas‑focused imaging in major nutrition cohorts. Measuring organ size early could identify high‑risk children before glucose spirals out of control.</p>



<p>“We are taking decisive steps to correct this,” said Schwarz, insisting that momentum will continue. Policies built on that momentum will decide whether type 5 becomes another silent killer or a preventable relic of poverty.</p>



<p>The study is published in <a href="https://journals.lww.com/bjem/fulltext/2025/05000/type_5_diabetes_mellitus__global_recognition_of_a.1.aspx" target="_blank" rel="noreferrer noopener"><em>Diabetes Care</em></a>.</p>



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<p>-----</p>

New type of diabetes is now officially recognized and linked to nutritional deficiencies

Type 5 diabetes is no longer a footnote. On April...

<p>Thirty‑five millennia may sound like a long time, yet for a mammal, it is practically yesterday. A new study uses whole‑genome data to show that the Norwegian lemming, <em>Lemmus lemmus</em>, split from its Siberian cousin only about 35,000 years ago.</p>



<p>“The Norwegian lemming is a key ecological species in the Fennoscandian tundra. Among other things, it serves as primary food for many predator <a href="https://www.earth.com/news/arctic-animals-evolved-in-different-ways-to-beat-the-cold/">species</a>, including some threatened ones such as the Arctic fox,” said David Díez del Molino, a researcher at the Centre for Palaeogenetics, <a href="https://www.su.se/">Stockholm University</a>.</p>



<h2 class="wp-block-heading" id="h-lemmings-shape-arctic-life">Lemmings shape Arctic life</h2>



<p>Ecologists have tracked lemming booms and busts for decades because those <a href="https://besjournals.onlinelibrary.wiley.com/doi/10.1046/j.1365-2656.1999.00258.x" target="_blank" rel="noreferrer noopener">cycles</a> ripple through the tundra food web, shaping the breeding success of Arctic foxes, owls, and even geese. </p>



<p>When rodent numbers crash, fox litters shrink, snowy owls skip nesting, and grasses rebound after seasons of heavy grazing.</p>



<p>Unlike most small <a href="https://www.earth.com/news/world-water-day-2025-preserving-glaciers-protecting-our-future/">mammals</a>, Norwegian lemmings overwinter aboveground by tunneling under snow, a habit that keeps them active when many rodents lie low. Their winter wanderings aerate soil, mix plant nutrients, and feed predators during the hungriest months.</p>



<p>During peak years, the species can reach densities of hundreds per acre. Yet its loud squeaks and bold charge‑and‑bite defense make predators think twice, granting the animal an outsized ecological voice relative to its three‑ounce frame.</p>



<h2 class="wp-block-heading" id="h-lemmings-became-a-separate-species">Lemmings became a separate species</h2>



<p>Researchers compared nine modern and two ancient lemming genomes and found a clean split from the Western Siberian lemming with no evidence of crossbreeding, even in areas where the two meet today. </p>



<p>That result stands in sharp contrast to polar bears and brown bears, whose DNA still shows <a href="https://pubmed.ncbi.nlm.nih.gov/22517859/" target="_blank" rel="noreferrer noopener">ancient admixture</a> from repeated hybridization events.</p>



<p>“Our findings indicate that the Norwegian lemming is among the most recently evolved <a href="https://www.earth.com/news/world-otter-day-2025-on-the-front-lines-of-a-habitat-crisis/">mammals</a>, diverging from its sister taxon, the Western Siberian lemming, at a remarkably shallow time depth,” said <a href="https://palaeogenetics.com/people/edana-lord/" target="_blank" rel="noreferrer noopener">Edana Lord</a>, a postdoctoral researcher at the Centre for Palaeogenetics.</p>



<p>The team’s high‑resolution sequencing also resolved relationships within the genus <em>Lemmus</em>, confirming that Eastern Siberian lemmings belong to a separate species and helping clean up a century of contested rodent taxonomy.</p>



<h2 class="wp-block-heading" id="h-a-species-born-in-an-ice-age">A species born in an ice age</h2>



<p>The divergence date places the split just before the <a href="https://www.science.org/doi/10.1126/science.1172873" target="_blank" rel="noreferrer noopener">Last Glacial Maximum</a>, when ice sheets peaked between roughly 26,500 and 19,000 years ago. </p>



<p>Glacial barriers likely trapped an ancestral lemming population in a Scandinavian refuge, cutting gene flow with Siberian relatives and setting the stage for rapid speciation.</p>



<p>Once the ice retreated, the newly minted Norwegian lineage expanded westward, but climatic swings had already written separation into the animals’ DNA. Modern population genetics shows no trace of later contact, suggesting that geography and behavior together kept the young species distinct.</p>



<p>Because the entire living population coalesces to a common ancestor only about 6,400 years ago, every Norwegian lemming alive today shares surprisingly shallow roots, a reminder that dramatic evolutionary change can happen fast.</p>



<h2 class="wp-block-heading" id="h-color-blocks-crossbreeding">Color blocks crossbreeding</h2>



<p>Hybridization often lingers for thousands of years after a split, yet these rodents seem to have slammed the door shut. </p>



<p>One reason may be their vivid black‑and‑yellow coat, a pattern that functions as an <a href="https://www.amnh.org/explore/news-blogs/aposematism-warning-signals" target="_blank" rel="noreferrer noopener">aposematic warning</a> and an instant badge of identity, reducing mating mistakes with the drab Siberian form.</p>



<p>Aggressive ritual boxing, loud chirps, and high‑speed chases further isolate the species by favoring individuals that court their own kind and bully outsiders away from snow burrows.</p>



<h2 class="wp-block-heading" id="h-genes-that-power-survival">Genes that power survival</h2>



<p>Sequencing uncovered unique changes in the <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3093193/" target="_blank" rel="noreferrer noopener">LYST pigment gene</a> that help produce the lemming’s splashy jacket, a mutation class also linked to altered melanosome function in laboratory mice. </p>



<p>The same region shows signs of a recent selective sweep, hinting at strong predator‑driven pressure for conspicuous colors.</p>



<p>Other <a href="https://pubmed.ncbi.nlm.nih.gov/30006135/" target="_blank" rel="noreferrer noopener">mutations</a> appear in <a href="https://www.ncbi.nlm.nih.gov/gene/53630" target="_blank" rel="noreferrer noopener">BCO1</a>, <a href="https://medlineplus.gov/genetics/gene/apob/" target="_blank" rel="noreferrer noopener">APOB</a>, and <a href="https://www.genecards.org/cgi-bin/carddisp.pl?gene=RELCH" target="_blank" rel="noreferrer noopener">RELCH</a> - genes involved in fat transport and storage; in mice, knocking out BCO1 triggers fatty‑liver disease and shifts cholesterol pathways. Extra‑efficient lipid metabolism may keep lemmings fueled through subzero winters when seeds are scarce.</p>



<p>The researchers also found clusters of rapidly evolving olfactory receptor genes, suggesting that a refined sense of smell guides the rodents through deep snow tunnels to mates, food, and lurking stoats.</p>



<h2 class="wp-block-heading" id="h-lessons-for-arctic-mammals">Lessons for Arctic mammals</h2>



<p>Climate upheaval can spin off new <a href="https://www.earth.com/news/aquatic-robot-inspired-by-flatworms-can-swim-in-harmony-with-nature/">species</a> in a geological blink, and the lemming’s youth underscores how quickly isolation plus selection can rewrite a mammal’s genetic blueprint. </p>



<p>Similar patterns play out in Arctic whales, foxes, and hares as shrinking ice opens and closes migration corridors.</p>



<p>“This work represents a big step in our understanding of lemming speciation and evolution,” said Love Dalén, a professor in <a href="https://utbildning.su.se/english/education/course-catalogue/bl/bl7082" target="_blank" rel="noreferrer noopener">Evolutionary Genomics at Stockholm University</a>. </p>



<p>Professor Dalén noted that tracing ancient DNA in more Pleistocene specimens could reveal exactly when each adaptive mutation took hold.</p>



<p>The study is published in <a href="https://www.pnas.org/doi/10.1073/pnas.2424333122" target="_blank" rel="noreferrer noopener"><em>Proceedings of the National Academy of Sciences</em></a>.</p>



<p> n  </p>

How Norwegian lemmings rapidly evolved into a new species

Thirty‑five millennia may sound like a long time, yet for...

<p>Sexual behavior and preference - whether in humans or animals - isn’t random. It’s shaped early on, during fetal development, by how the brain responds to hormones like androgens (male sex hormones). </p>



<p>This early exposure is known to affect adult traits like <a href="https://www.earth.com/news/relentless-sex-drive-may-lead-northern-quolls-to-extinction/">sex drive</a> and cognition. But there's been one big obstacle: how do you measure that influence without invasive methods?</p>



<h2 class="wp-block-heading" id="h-rat-fingers-hint-at-sexual-behavior">Rat fingers hint at sexual behavior </h2>



<p>Researchers from <a href="https://www.okayama-u.ac.jp/index_e.html">Okayama University</a> in Japan may have found an answer - by looking at rats’ fingers.</p>



<p>In a recent study published on May 14, 2025, a team led by Professor Hirotaka Sakamoto and Dr. Himeka Hayashi found that a simple finger measurement - the ratio of the second digit to the fourth digit, known as 2D:4D - can predict sexual behavior and preference in rats.</p>



<p>This digit ratio has been studied in humans for years. On average, men tend to have a lower 2D:4D ratio than women, meaning their index fingers are shorter relative to their ring fingers. </p>



<p>That difference has been linked to prenatal androgen exposure. It’s also been tied to traits like <a href="https://www.earth.com/news/practicing-yoga-nidra-improves-sleep-memory-and-cognition/">cognition</a>, <a href="https://www.earth.com/news/personality-traits-are-not-strongly-inherited-from-parents/">personality</a>, and sexual orientation. But surprisingly, there hasn’t been much research testing whether this holds true in other animals. That’s what drew the researchers to rats.</p>



<h2 class="wp-block-heading" id="h-shorter-fingers-stronger-sex-drive">Shorter fingers, stronger sex drive</h2>



<p>“We found that the 2D:4D ratio serves as a reliable biological marker for predicting sexual activity in rats,” said Sakamoto. “Rats with shorter second digits were not only more sexually active but also showed a clear preference for female scent.”</p>



<p>Building on their initial measurements, the team then ran mating trials to observe <a href="https://www.earth.com/news/science-behind-predicting-and-changing-human-behavior/">behavior</a>.</p>



<p>The results were clear. Male rats that ejaculated during their first encounter had shorter second digits compared to those that didn’t. </p>



<p>These males also showed signs of higher sexual drive: they ejaculated more often, did so more quickly, and had stronger erectile function.</p>



<h2 class="wp-block-heading" id="h-the-scent-of-sexual-behavior">The scent of sexual behavior </h2>



<p>To go beyond behavior and look at preference, the researchers ran a simple but telling test. They placed male rats in a cage with two kinds of bedding: one scented by females, and the other by males.</p>



<p>All the male rats initially explored the male-scented bedding. But only those with shorter second digits stayed interested in the female-scented bedding. They sniffed, explored, and spent more time with it - indicating a clear sexual preference.</p>



<p>“While most studies have only linked the digit ratio to morphological sex differences, we noticed a surprising lack of research connecting digit ratio to the biological basis of sex itself - especially sexual activity and preference,” notes Hayashi. “This curiosity marked the start of our study.”</p>



<h2 class="wp-block-heading" id="h-fingers-mirror-brain-wiring">Fingers mirror brain wiring</h2>



<p>Beyond offering insight into rat behavior, the study points to a deeper question: how early hormone exposure shapes the brain in lasting ways.</p>



<p>Before birth, hormone exposure might wire our brains in ways that the 2D:4D ratio later reflects - potentially shaping complex behaviors like sexual orientation or emotional attachment.</p>



<p>“Our results suggest a profound link between the body and mind, with significant scientific and clinical implications,” said Sakamoto. “Simply examining our fingers could one day help identify aspects of our behavioral tendencies.”</p>



<p>The findings also offer a practical model for exploring biological questions that are difficult - or impossible - to study directly in humans. </p>



<p>Because 2D:4D is also connected to cognitive traits and mental health conditions, this research could help explain sex-based differences in disorders like <a href="https://www.earth.com/news/toddler-screen-time-linked-to-atypical-sensory-behaviors/">autism</a>, <a href="https://www.earth.com/news/how-gut-bacteria-morganella-morganii-could-cause-depression-not-a-brain-disorder/">depression</a>, or attachment issues.</p>



<h2 class="wp-block-heading" id="h-biology-is-not-the-whole-story">Biology is not the whole story</h2>



<p>While the findings are compelling, they also raise important questions. For one, it’s still unclear how well results from rats translate to humans. </p>



<p>Rats provide a useful model for controlled experiments, but human sexuality is influenced by many layers - cultural, social, psychological - that go far beyond biology.</p>



<p>The researchers also focused only on male rats. Future studies will need to explore whether similar patterns hold true for females, and how other factors like environment or stress interact with digit ratios to shape behavior.</p>



<p>Another key question is causation. Rats with shorter 2D:4D finger ratios tend to show more sexual activity and stronger preferences, but scientists aren’t yet sure whether the digit ratio drives this behavior - or if both stem from shared prenatal influences.</p>



<p>None of this takes away from the value of the study. But it highlights the importance of treating biological markers like 2D:4D as part of a much larger picture. </p>



<p>The full study was published in the journal <em><a href="https://www.jstage.jst.go.jp/article/expanim/advpub/0/advpub_24-0159/_article">Experimental Animals</a></em>.</p>



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<p>-----</p>

Does your finger length predict sexual behavior? A rat study says yes

Sexual behavior and preference - whether in humans or animals...


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