Today's Image of the Day from the European Space Agency features the spiral galaxy UGC 11397 in the constellation Lyra (The Lyre).



The light captured in this striking image traveled for 250 million years before reaching the NASA/ESA <a href="https://www.earth.com/news/35-years-of-hubble-the-telescope-that-changed-our-view-of-the-universe/">Hubble Space Telescope</a>.



“At first glance, UGC 11397 appears to be an average spiral galaxy: it sports two graceful spiral arms that are illuminated by stars and defined by dark, clumpy clouds of dust,” noted ESA.



“What sets UGC 11397 apart from a typical spiral lies at its center, where a supermassive black hole containing 174 million times the mass of the Sun is growing.”&nbsp;



<h2 class="wp-block-heading" id="h-a-hidden-powerhouse">A hidden powerhouse</h2>



As the <a href="https://www.earth.com/news/largest-oldest-black-hole-jet-ever-seen-is-size-of-three-milky-ways-j1601-3102/">black hole</a> consumes gas, dust, and even entire stars from its surroundings, the infalling material heats up dramatically, producing a dazzling display of energy.&nbsp;



These emissions span the electromagnetic spectrum - from gamma rays to radio waves - and can flare or fade unpredictably.&nbsp;



“But in some galaxies, including UGC 11397, thick clouds of dust hide much of this energetic activity from view in optical light,” explained ESA.



“Despite this, UGC 11397's actively growing black hole was revealed through its bright X-ray emission - high-energy light that can pierce the surrounding dust.”&nbsp;



Its distinctive signature has earned UGC 11397 the classification of a Type 2 Seyfert galaxy. This category describes active galaxies whose central regions are obscured in visible light by a doughnut-shaped cloud of dust and gas.



<h2 class="wp-block-heading" id="h-galaxy-and-black-hole-growth">Galaxy and black hole growth</h2>



“Using Hubble, researchers will study hundreds of galaxies that, like UGC 11397, harbor a supermassive black hole that is gaining mass,” noted ESA.&nbsp;



“The Hubble observations will help researchers weigh nearby supermassive black holes, understand how black holes grew early in the universe’s history, and even study how stars form in the extreme environment found at the very center of a galaxy.”



Studying <a href="https://www.earth.com/news/hidden-galaxies-discovery-would-upend-current-understanding-of-universe/">galaxies</a> like UGC 11397 also offers insight into the mysterious relationship between supermassive black holes and their host galaxies.&nbsp;



Despite residing at the heart of galaxies, these black holes influence their surroundings on a much larger scale, often regulating the formation of stars and even shaping the structure of the galaxy itself.



<h2 class="wp-block-heading" id="h-tracing-black-hole-origins">Tracing black hole origins</h2>



One of the key questions astronomers hope to answer is how these black holes grow so massive in the first place.&nbsp;



While some appear to have formed gradually over billions of years, others - especially those in the early universe - seem to have reached enormous sizes much more quickly. 



Observations of galaxies such as UGC 11397 provide crucial data to test different growth scenarios.



<h2 class="wp-block-heading" id="h-a-clearer-picture-of-cosmic-evolution">A clearer picture of cosmic evolution</h2>



By combining Hubble’s observations with data from other telescopes, including those that detect X-rays and radio waves, researchers can build a more complete picture of how matter behaves around black holes.&nbsp;



This multi-wavelength approach is essential for studying objects obscured by dust, like Type 2 Seyfert galaxies, where optical views alone can be misleading.



Hubble’s sharp vision also allows astronomers to examine the surrounding galactic disk and spiral arms in high detail. 



These structures hold clues about recent star formation, galactic dynamics, and how gas flows toward the center - fueling both star birth and black hole growth.



<h2 class="wp-block-heading" id="h-black-hole-energy-in-active-galaxies">Black hole energy in active galaxies</h2>



In many active <a href="https://www.earth.com/news/thousands-of-galaxies-revealed-in-a-single-webb-image/">galaxies</a>, the energy released by the central black hole can blast out powerful winds or jets that affect star formation. These feedback processes can either shut down or stimulate the creation of new stars, depending on the conditions.&nbsp;



Understanding when and how this feedback occurs is another major goal of Hubble’s ongoing studies.



UGC 11397 is just one of many galaxies being surveyed as part of broader efforts to trace the cosmic history of <a href="https://www.earth.com/news/black-holes-turn-into-white-holes-and-blast-out-matter-and-time-runs-backwards/">black hole</a> activity.&nbsp;



Projects such as these are helping scientists map how common active galactic nuclei are, how their properties evolve over time, and how they relate to galaxy mergers and other large-scale events.



The wealth of information gathered from galaxies like UGC 11397 is not only deepening our understanding of black holes but also refining models of galaxy formation and evolution.&nbsp;



With each new observation, astronomers are piecing together the vast and complex puzzle of how galaxies and their central engines co-evolve across cosmic time.



Image Credit: ESA/Hubble &amp; NASA, M. J. Koss, A. J. Barth



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Hubble reveals a black hole hidden in a distant galaxy

Today's Image of the Day from the European Space Agency features the spiral galaxy UGC 11397 in the constellation Lyra (The Lyre). The light captured in this striking image traveled for 250 million years before reaching the NASA/ESA Hubble Space Telescope. “At first glance, UGC 11397 appears to be an average spiral galaxy: it sports two graceful spiral arms that are illuminated by stars and defined by dark, clumpy clouds of dust,” noted ESA. “What sets UGC 11397 apart from a typical spiral...

Today's Image of the Day from NASA Earth Observatory features the Iliamna Volcano, which recently experienced a burst of seismic activity on June 15, 2025.&nbsp;



According to experts, the tremors were not likely to be warning signs of an impending eruption. Instead, the shaking was probably triggered by ice or rock avalanches.&nbsp;



The <a href="https://www.earth.com/news/magma-layer-keeps-the-yellowstone-supervolcano-dormant/">volcano</a> is currently considered dormant, with no elevated alert levels or signs of eruptive activity.



“Towering more than 10,000 feet (3,000 meters) over Cook Inlet, Alaska’s Iliamna Volcano last erupted in 1867. Once every couple of years, however, the mountain still rumbles,” noted <a href="https://earthobservatory.nasa.gov/images/154461/iliamna-volcano-ready-to-rumble">NASA</a>.



“Its murmurs tend not to be signs of volcanic unrest but rather the signature of avalanches large enough to register on nearby seismic and infrasound instruments.”



<h2 class="wp-block-heading" id="h-the-dramatic-landscape-of-iliamna-nbsp">The dramatic landscape of Iliamna&nbsp;</h2>



Iliamna is a glacier-covered volcano about 130 miles southwest of Anchorage and 30 miles southwest of the more active Redoubt Volcano. Both are located in the Lake Clark National Park and Preserve.&nbsp;



Glaciers have carved deep, U-shaped valleys that stretch from Iliamna toward the sea. Just south of the peak, Chinitna Bay is a popular spot for seeing brown bears.



The region’s dramatic terrain is the result of a long history of <a href="https://www.earth.com/news/earthquake-activity-will-increase-due-to-glacial-retreat/">glacial activity</a>, tectonic uplift, and volcanic shaping. Snow and ice persist year-round at high elevations, feeding creeks and rivers that support wildlife and vegetation at lower altitudes.&nbsp;



The contrast between icy peaks and lush coastal plains makes Iliamna's surroundings both ecologically diverse and visually striking.



<h2 class="wp-block-heading" id="h-a-flurry-of-seismic-activity-nbsp">A flurry of seismic activity&nbsp;</h2>



The image of Iliamna Volcano was captured on June 10, 2025, by the Operational Land Imager (OLI) on Landsat 8. According to the Alaska Volcano Observatory (AVO), a flurry of shaking rattled Iliamna a few days later.



“Seismic activity picked up at about 4:30 a.m. local time on June 15 and ramped up to a ‘nearly continuous’ rate, the AVO reported. It slowed to a cadence of about one seismic event per minute and then returned to background levels around 2:30 p.m.,” NASA reported.



“The AVO did not have enough information as of June 16 to determine the size and location of any slide that may have occurred that day. However, the signals they recorded were similar to those caused by the initial slipping between rock and ice that preceded large avalanches on the volcano in the past, they said.”



<h2 class="wp-block-heading" id="h-rock-and-ice-avalanches-on-iliamna-nbsp">Rock and ice avalanches on Iliamna&nbsp;</h2>



Glacial ice, heat from the <a href="https://www.earth.com/news/earths-orbit-may-trigger-massive-volcanic-eruptions/">volcano</a>, and weakened rock come together on Iliamna’s slopes to create the perfect setup for huge landslides, noted NASA.&nbsp;



Researchers say that it's unusual to see so many large ice and rock avalanches in one place, making Iliamna a valuable natural lab for studying how and why these events happen. 



While Iliamna is far from towns or cities, similar conditions in more populated mountain areas could be dangerous for nearby communities.



<h2 class="wp-block-heading" id="h-glacier-melt-and-slope-stability">Glacier melt and slope stability</h2>



In recent years, scientists have warned that warming temperatures are accelerating <a href="https://www.earth.com/news/astonishing-glacier-retreat-in-the-arctic-signals-climate-disaster/">glacier melt</a> across Alaska, potentially destabilizing the slopes of glacier-covered volcanoes like Iliamna.&nbsp;



As ice retreats and thins, it can remove the natural support that holds rock in place, increasing the risk of avalanches and landslides.



Climate change may also be influencing the frequency and intensity of these non-eruptive seismic events. As permafrost thaws and glaciers lose mass, the delicate balance between ice, rock, and heat is disrupted, sometimes leading to sudden and dramatic collapses.



<h2 class="wp-block-heading" id="h-indicators-of-environmental-change">Indicators of environmental change</h2>



Volcanoes such as Iliamna serve as critical indicators of broader environmental changes. The patterns of seismic activity and ice loss on their slopes offer researchers valuable insight into how the Earth's cryosphere is responding to global warming.



While Iliamna is a remote volcano that poses no direct threat to people or communities, its behavior raises important questions about the future stability of other glaciated volcanoes worldwide. 



As climate change continues to reshape <a href="https://www.earth.com/news/mountain-plants-are-not-safe-from-rapid-climate-change/">mountain environments</a>, understanding the interactions between ice, rock, and volcanic heat will be vital for anticipating hazards in both high-latitude and high-altitude regions.



Image Credit: NASA Earth Observatory&nbsp;



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Iliamna Volcano rumbles as glaciers shift in Alaska

Today's Image of the Day from NASA Earth Observatory features...

Tropical Cyclone Hikaa reaches the Arabian Peninsula Today's Image of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> features Tropical Cyclone Hikaa, which brought damaging winds and rain into the Arabian Peninsula.

When the storm made landfall over Oman on September 24, it had maximum wind speeds of up to 80 miles per hour. Tropical Cyclone Hikaa reaches the Arabian Peninsula

It is not very common for cyclones to reach the Arabian Sea in the North Indian Ocean. However, in 2018, three significant cyclones pushed all the way up to the Arabian <a href="https://en.wikipedia.org/wiki/Arabian_Peninsula">Peninsula</a>. 

The image was captured by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s <a href="http://www.earth.com/image/sunglint-on-the-mediterranean-sea/">Terra</a> satellite as the outer bands of Hikaa moved over Oman.

Arabian Peninsula is the largest peninsula in the world, at 3,237,500 km2 (1,250,000 sq mi). The Peninsula consists of six countries: Kuwait, Oman, Qatar, Saudi Arabia, the United Arab Emirates, and Yemen. The peninsula formed as a result of the rifting of the Red Sea between 56 and 23 million years ago, and is bordered by the Red Sea to the west and southwest, the Persian Gulf to the northeast, the Levant to the north and the Indian Ocean to the southeast. The peninsula plays a critical geopolitical role in the Arab world due to its vast reserves of oil and natural gas.

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By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Image Credit: NASA Earth Observatory 

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Tropical Cyclone Hikaa reaches the Arabian Peninsula

Tropical Cyclone Hikaa reaches the Arabian Peninsula Today's Image of...

Arctic sea ice continues its downward trend Today's Image of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> shows shrinking sea ice in the Arctic, which reached its annual summer minimum on September 18, 2019.

According to <a href="https://en.wikipedia.org/wiki/NASA">NASA</a>, the extent of ice cover this year has tied 2007 and 2016 as the second lowest in the satellite record, which covers the last four decades. Arctic sea ice continues its downward trend

In 2019, the Arctic sea ice cap shrank to 1.6 million square miles as a result of increasing air and water temperatures.

"This year’s minimum shows that there is no sign that the sea ice cover is rebounding,” said Claire Parkinson, a senior scientist at NASA’s Goddard Space Flight Center. “The long-term trend for the Arctic sea ice extent has been definitively downward.”

The Arctic Ocean is the smallest and shallowest of the world's five major oceans. It is also known as the coldest of all the oceans. The International <a href="http://www.earth.com/news/hydroxychloroquine-is-not-an-effective-covid-19-treatment/">Hydrographic</a> Organization (IHO) recognizes it as an ocean, although some oceanographers call it the Arctic Sea. It is sometimes classified as an estuary of the Atlantic Ocean, and it is also seen as the northernmost part of the all-encompassing World Ocean.

 --

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Image Credit: NASA Earth Observatory 

&nbsp;

Arctic sea ice continues its downward trend

Arctic sea ice continues its downward trend Today's Image of...

Phytoplankton blooms persist in the North Atlantic Ocean Today's Image of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> features blooms of phytoplankton in the North Atlantic Ocean, which have been unusually persistent and far-reaching this month. 

In the ocean near Newfoundland, Canada, the floating organisms had an abundance of sunlight, warm water, and nutrients which allowed them to thrive. Phytoplankton blooms persist in the North Atlantic Ocean

“This is not our typical fall phytoplankton bloom, which would be made up of diatoms,” said marine biologist Cynthia McKenzie of Fisheries and Oceans Canada. She explained that the late bloom is likely a result of “several weeks of sunlight - pretty rare for us in September - and higher than normal temperatures."

The widespread bloom even survived Hurricane Dorian, which stormed through the region in early September. The Atlantic Ocean occupies an elongated, S-shaped basin extending longitudinally between <a title="Europe" href="https://en.wikipedia.org/wiki/Europe">Europe</a> and <a title="Africa" href="https://en.wikipedia.org/wiki/Africa">Africa</a> to the east, and the <a title="Americas" href="https://en.wikipedia.org/wiki/Americas">Americas</a> to the west. As one component of the interconnected <a title="World Ocean" href="https://en.wikipedia.org/wiki/World_Ocean">World Ocean</a>, it is connected in the north to the <a title="Arctic Ocean" href="https://en.wikipedia.org/wiki/Arctic_Ocean">Arctic Ocean</a>, to the <a title="Pacific Ocean" href="https://en.wikipedia.org/wiki/Pacific_Ocean">Pacific Ocean</a> in the southwest, the <a title="Indian Ocean" href="https://en.wikipedia.org/wiki/Indian_Ocean">Indian Ocean</a> in the southeast, and the <a title="Southern Ocean" href="https://en.wikipedia.org/wiki/Southern_Ocean">Southern Ocean</a> in the south (other definitions describe the Atlantic as extending southward to <a title="Antarctica" href="https://en.wikipedia.org/wiki/Antarctica">Antarctica</a>). The Atlantic Ocean is divided into two parts, by the <a title="Equatorial Counter Current" href="https://en.wikipedia.org/wiki/Equatorial_Counter_Current">Equatorial Counter Current</a>, with the North(ern) Atlantic Ocean and the South(ern) Atlantic Ocean at about <a title="8th parallel north" href="https://en.wikipedia.org/wiki/8th_parallel_north">8°N</a>

"I thought the hurricane would have had an effect, but if anything it seems to have fueled its continuation,” said McKenzie. “Most of the heavy wind was on the western part of Newfoundland, so what we had was some wave action which may have brought more nutrients to the bloom from further down in the water column.”

The image was captured on September 1, 2019 by the Moderate Resolution Imaging Spectroradiometer (MODIS) on <a href="https://www.earth.com/video/exciting-nasa-missions-coming-in-2021/">NASA’s</a> Aqua satellite.

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By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Image Credit: NASA Earth Observatory 

&nbsp;

Phytoplankton blooms persist in the North Atlantic

Phytoplankton blooms persist in the North Atlantic Ocean Today's Image...

Tropical Storm Imelda brings extreme rainfall to Texas Today's Image of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> maps the extreme rainfall in southeast Texas from Tropical Storm Imelda.

The system pulled in heat and moisture from the Gulf of Mexico before moving very slowly over Houston and Beaumont, causing damaging flash floods.

The brightest areas on the map represent the highest rainfall amounts, with some places receiving as much as 30 inches from September 17 to September 20, 2019. 

The data comes from the Integrated Multi-Satellite Retrievals for the Global Precipitation Measurement (GPM) mission.Tropical Storm Imelda was the fifth-wettest tropical cyclone on record in the continental United States, causing devastating and record-breaking floods in southeast Texas. The eleventh tropical cyclone and ninth named storm of the 2019 Atlantic hurricane season, Imelda formed out of an upper-level low that developed in the Gulf of Mexico and moved westward. Little development occurred until the system was near the Texas coastline, where it rapidly developed into a tropical storm before moving ashore shortly afterward on September 17. Imelda weakened after landfall, but continued bringing large amounts of flooding rain to Texas and Louisiana, before dissipating on September 21.

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By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Image Credit: NASA Earth Observatory 

&nbsp;

Tropical Storm Imelda brings extreme rainfall to Texas

Tropical Storm Imelda brings extreme rainfall to Texas Today's Image...

Today's Image of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> features Kuwait Bay, where one of the world's largest bridges has been constructed to connect Bay Island North and Bay Island South.

The 30-mile Sheikh Jaber Al-Ahmad Al-Sabah Causeway opened in May after five years of planning and more than three billion dollars in costs.

Construction companies made an effort to preserve the ecosystem near the bay, specifically for green tiger shrimp. To lure the shrimp away from the site, an alternative breeding area was created with 1,000 rock and reef blocks. 

The photograph was captured on September 8, 2019 by the Operational Land Imager on Landsat 8.

  --

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Image Credit: NASA Earth Observatory 

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Massive bridge opens in Kuwait Bay

Prehistoric monument reappears after 50 years Today's Image of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> features the Peraleda de la Mata coast of Spain, where a megalithic monument that has been submerged for 50 years has now reappeared.

The Spanish government built the Valdecañas Reservoir in 1963 to provide water and electricity to underdeveloped parts of western <a href="https://www.bing.com/search?q=spain&amp;form=EDGEAR&amp;qs=PF&amp;cvid=5b51013ff6d343e58e06b1d8c7897d5b&amp;cc=US&amp;setlang=en-US&amp;elv=AY3%21uAY7tbNNZGZ2yiGNjfNcI5dP9v9G08gsHOyyYrAtkkvuZkPJMNHatocLu*HXVSIHGmF4JzIy9zHG1xyZewzm7PwbJiGvDB8O1kdMSCwh&amp;plvar=0&amp;PC=HCTS">Spain</a>. When the reservoir was developed, however, it flooded some inhabited areas as well as large stone monuments. Prehistoric monument reappears after 50 years

Dry and hot conditions caused the lake to shrink this summer, and one of these megaliths - known as the Dolmen of Guadalperal - managed to resurface. Prehistoric monument reappears after 50 years.

The image was captured on July 25, 2019 by the Operational Land Imager on Landsat 8.

With an area of 505,990 km2 (195,360 sq mi), Spain is the largest country in Southern Europe, the second-largest country in Western Europe and the European Union, and the fourth-largest country by area on the European continent. With a population exceeding 47.3 million, Spain is the sixth-most populous country in Europe, and the fourth-most populous country in the European Union. Spain's capital and largest city is Madrid; other major urban areas include Barcelona, Valencia, Seville, Zaragoza, Málaga, and Bilbao.

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By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Image Credit: NASA Earth Observatory 

&nbsp;

Prehistoric monument reappears after 50 years

Prehistoric monument reappears after 50 years Today's Image of the...

Hundreds of fires are burning across Indonesia Today's Image of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> shows thick smoke lingering over wildfires across Indonesia.

Although most of the fires were set deliberately to clear land for farming, the dry conditions this year are exceptionally dangerous for human health and the environment.

The regions of Kalimantan, the Indonesian part of Borneo, and Sumatra are covered in a blanket of smoke that is moving across parts of <a href="https://www.bing.com/search?q=south+east+asia&amp;form=EDGEAR&amp;qs=PF&amp;cvid=27e1476e98284ca9896134833667fc12&amp;cc=US&amp;setlang=en-US&amp;elv=AY3%21uAY7tbNNZGZ2yiGNjfNcI5dP9v9G08gsHOyyYrAtczcOfaFLWPNYvdd4ABYJceIDJiMVcFlFrO8PUutS8hjNQEijPji5XnAL8vX7ermE&amp;plvar=0&amp;PC=HCTS">Southeast Asia.</a>

According to news reports, many schools have closed and several airports have canceled or delayed flights in recent weeks.

This image was captured on September 15, 2019 by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite.

The sovereign state is a presidential, constitutional republic with an elected legislature. It has 34 provinces, of which five have special status. The country's capital, Jakarta, is the second-most populous urban area in the world. The country shares land borders with Papua New Guinea, East Timor, and the eastern part of Malaysia. Other neighbouring countries include Singapore, Vietnam, the Philippines, Australia, Palau, and India's Andaman and Nicobar Islands. Despite its large population and densely populated regions, Indonesia has vast areas of wilderness that support one of the world's highest levels of biodiversity.

The Indonesian archipelago has been a valuable region for trade since at least the 7th century when Srivijaya and later Majapahit traded with entities from mainland China and the Indian subcontinent. Local rulers gradually absorbed foreign influences from the early centuries and Hindu and Buddhist kingdoms flourished

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By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Image Credit: NASA Earth Observatory 

&nbsp;

Hundreds of fires are burning across Indonesia

Hundreds of fires are burning across Indonesia Today's Image of...

Trichodesmium bloom near the Great Barrier Reef Today's Image of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> features a bloom of Trichodesmium near the Great Barrier Reef off northeast Australia. 

Trichodesmium blooms start off with a yellowish-brown color when the bloom is healthy, turn green as it begins to decay, and turn white after the pigments decay.

The cyanobacteria plays an important role in the ocean because it supplies large quantities of nitrogen for marine ecosystems, accounting for about 60 to 80 percent of nitrogen fixation in the ocean.

This image was captured on September 1, 2019 by the Operational Land Imager on Landsat 8.A large part of the reef is protected by the <a title="Great Barrier Reef Marine Park" href="https://en.wikipedia.org/wiki/Great_Barrier_Reef_Marine_Park">Great Barrier Reef Marine Park</a>, which helps to limit the impact of human use, such as fishing and tourism. Other <a title="Environmental threats to the Great Barrier Reef" href="https://en.wikipedia.org/wiki/Environmental_threats_to_the_Great_Barrier_Reef">environmental pressures on the reef</a> and its <a title="Ecosystem" href="https://en.wikipedia.org/wiki/Ecosystem">ecosystem</a> include <a title="Surface runoff" href="https://en.wikipedia.org/wiki/Surface_runoff">runoff</a>, <a title="Climate change" href="https://en.wikipedia.org/wiki/Climate_change">climate change</a> accompanied by mass <a title="Coral bleaching" href="https://en.wikipedia.org/wiki/Coral_bleaching">coral bleaching</a>, dumping of dredging sludge and cyclic population outbreaks of the <a title="Crown-of-thorns starfish" href="https://en.wikipedia.org/wiki/Crown-of-thorns_starfish">crown-of-thorns starfish</a>. According to a study published in October 2012 by the <a class="mw-redirect" title="Proceedings of the National Academy of Sciences" href="https://en.wikipedia.org/wiki/Proceedings_of_the_National_Academy_of_Sciences">Proceedings of the National Academy of Sciences</a>, the reef has lost more than half its coral cover since 1985, a finding reaffirmed by a 2020 study which found over half of the reef's coral cover to have been lost between 1995 and 2017, with the effects of a widespread 2020 bleaching event not yet quantified

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By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Image Credit: NASA Earth Observatory 

&nbsp;

Trichodesmium bloom near the Great Barrier Reef

Trichodesmium bloom near the Great Barrier Reef Today's Image of...

The machinery inside of each human cell usually behaves like a dimmer, turning genes up or down as needed. A new analysis shows that hundreds of human genes shun the dimmer and act more like a light switch, clicking fully on or off depending on the person. 



The study was led by geneticist Omer Gokcumen at the <a href="https://www.buffalo.edu/">University at Buffalo</a>. His research reveals that this switch-like behavior may influence everything from fertility to cancer risk, depending on which genes are on or off.



<h2 class="wp-block-heading" id="h-the-light-switch-gene-mystery">The light-switch gene mystery</h2>



Early <a href="https://www.ncbi.nlm.nih.gov/books/NBK26872/" target="_blank" rel="noreferrer noopener">work</a> on the <a href="https://www.sciencedirect.com/topics/biochemistry-genetics-and-molecular-biology/lac-operon" target="_blank" rel="noreferrer noopener">lac operon</a> in <a href="https://www.cdc.gov/ecoli/about/index.html" target="_blank" rel="noreferrer noopener">Escherichia coli</a> proved that a gene can be either silent or roaring, nothing in between. 



Researchers long assumed that such binary behavior was rare in <a href="https://www.earth.com/news/scientists-raised-mouse-born-from-two-male-parents-to-adulthood-imprinting-genes/">humans</a> because most traits need finer control. Yet the new report argues the opposite, showing that on‑off genes are widespread and often tied to illness.



Gene expression is simply the act of reading DNA and making proteins; most genes rise and fall smoothly. <a href="https://www.nature.com/articles/s41467-025-60513-x" target="_blank" rel="noreferrer noopener">Switch‑like genes</a>, by contrast, settle into either high or low camps, with few residents in the middle.



<h2 class="wp-block-heading" id="h-hundreds-of-switch-genes-discovered">Hundreds of switch genes discovered</h2>



The team mined the <a href="https://www.gtexportal.org/home/" target="_blank" rel="noreferrer noopener">Genotype‑Tissue Expression Project</a>, a public atlas of 943 volunteers covering 27 tissues. 



They applied a statistical “dip test” to 516,267 gene–tissue pairs and flagged 473 genes whose activity followed a crisp bimodal <a href="https://www.earth.com/news/how-flowers-grow-perfectly-despite-chaotic-gene-activity/">pattern</a>.



“We believe switch‑like genes could one day be used to diagnose and perhaps even treat diseases,” said Gokcumen. 



Only 40 of those genes showed on‑off states everywhere, implying <a href="https://www.sciencedirect.com/science/article/pii/S0966842X1630066X" target="_blank" rel="noreferrer noopener">hard‑wired DNA control</a>, while the rest flipped only in certain organs. 



<h2 class="wp-block-heading" id="h-switch-gene-linked-to-health">Switch gene linked to health</h2>



Many of the 473 toggling genes sit at the heart of immune defense, metabolism, and cancer pathways. 



Low expression of <a href="https://www.genecards.org/cgi-bin/carddisp.pl?gene=USP32P2" target="_blank" rel="noreferrer noopener">USP32P2</a>, for instance, has been associated with male infertility, while off‑states in <a href="https://www.genecards.org/cgi-bin/carddisp.pl?gene=FAM106A" target="_blank" rel="noreferrer noopener">FAM106A</a> may blunt the body’s response to COVID‑19.



Seven switch‑like genes in vaginal tissue, including <a href="https://www.genecards.org/cgi-bin/carddisp.pl?gene=ALOX12" target="_blank" rel="noreferrer noopener">ALOX12</a> and <a href="https://www.genecards.org/cgi-bin/carddisp.pl?gene=KRT1" target="_blank" rel="noreferrer noopener">KRT1</a>, shut down together in some women and correlate with <a href="https://www.health.harvard.edu/a_to_z/vaginal-atrophy-atrophic-vaginitis-a-to-z" target="_blank" rel="noreferrer noopener">vaginal atrophy</a>, a postmenopausal thinning of the mucosa. 



“This coordinated silencing hints at master switches we could eventually toggle therapeutically,” noted first author <a href="https://scholar.google.com/citations?user=Ns4R9VQAAAAJ&amp;hl=en" target="_blank" rel="noreferrer noopener">Alber Aqil</a>.



<h2 class="wp-block-heading" id="h-hormones-switch-genes-on-or-off">Hormones switch genes on or off</h2>



The pattern of tissue‑specific switching pointed to hormones. In breast tissue, 157 of 158 switch‑like genes were far more active in women than in men, matching the estrogen-rich <a href="https://www.earth.com/news/luca-last-universal-common-ancestor-progenitor-all-life-on-earth/">environment</a>.



When systemic <a href="https://www.ncbi.nlm.nih.gov/books/NBK559297/" target="_blank" rel="noreferrer noopener">estrogen</a> falls after menopause, the seven atrophy‑linked genes often flip off in the vagina, leaving the epithelium fragile. 



About half of postmenopausal women experience symptoms of vaginal atrophy, yet most never seek help.



<h2 class="wp-block-heading" id="h-epigenetics-plays-a-role">Epigenetics plays a role</h2>



Some switch-like genes are influenced not just by DNA or hormones but by <a href="https://www.nature.com/articles/npp2012112" target="_blank" rel="noreferrer noopener">DNA methylation</a>, a chemical tag that turns genes off by altering how DNA is read. 



In tissues like the breast and prostate, researchers found a strong negative correlation between gene expression and methylation at nearby <a href="https://www.sciencedirect.com/topics/neuroscience/cpg-site" target="_blank" rel="noreferrer noopener">CpG sites</a>, which are common control points in the genome.



In the breast, for example, 71 switch-like genes showed this pattern, suggesting that <a href="https://link.springer.com/rwe/10.1007/978-3-642-16483-5_1944" target="_blank" rel="noreferrer noopener">epigenetic silencing</a> explains why some people have these genes off. 



That means two people with the same DNA sequence might express the gene differently depending on their epigenetic landscape, which can change over time due to age, stress, or environmental exposure.



<h2 class="wp-block-heading" id="h-most-switches-are-tissue-specific">Most switches are tissue‑specific</h2>



Out of the 473 switch-like genes identified, only a small group flipped on or off in every tissue. Most behaved like switches in just one or two types of tissue, such as the breast, colon, or vagina. 



This tissue-specific pattern suggests that local conditions - like hormone levels or tissue-specific master regulators, control whether the switch flips.



Within each tissue, multiple switch-like genes tend to flip together, showing strong <a href="https://www.sciencedirect.com/topics/medicine-and-dentistry/gene-co-expression-network" target="_blank" rel="noreferrer noopener">gene-to-gene co-expression</a>. This clustering means they may be controlled by the same upstream signal. 



For instance, in the breast, several genes turned on together in females and remained off in many males, reflecting the influence of estrogen on the tissue’s gene activity.



<h2 class="wp-block-heading" id="h-switch-genes-aid-diagnosis">Switch genes aid diagnosis</h2>



On‑off states make ideal biomarkers because a simple assay can sort patients into yes‑or‑no categories. <a href="https://pmc.ncbi.nlm.nih.gov/articles/PMC9580661/" target="_blank" rel="noreferrer noopener">Topical estradiol</a>, already used for atrophy, restores vaginal pH and thickens the lining by turning many of the same genes back on.



Universal switch‑like genes, often governed by structural variants, suggest another route: DNA testing could flag individuals whose deleted or silenced <a href="https://pmc.ncbi.nlm.nih.gov/articles/PMC6175939/" target="_blank" rel="noreferrer noopener">USP32P2 allele</a> raises infertility risk. 



The study argues that long‑read sequencing will uncover the missing structural variants and complete the binary map.



Beyond hormones, environmental exposures may tilt genetic switches, creating a fertile ground for gene‑environment studies. 



Cataloging on‑off genes, the authors say, brings us closer to personalized medicine that treats the cause, not the symptom.



The study is published in the journal <a href="https://www.nature.com/articles/s41467-025-60513-x" target="_blank" rel="noreferrer noopener">Nature Communications</a>.



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Some genes may predict infertility and disease by flipping like a light switch

The machinery inside of each human cell usually behaves like...

Every fleeting glance you take of your surroundings sets off a chain reaction inside your skull, shuttling retinal signals to a tiny midbrain hub. New findings show that this relay does more than position your eyes; it also helps you decide what those eyes are seeing.



Scientists from the <a href="https://www.uchicago.edu/en" target="_blank" rel="noreferrer noopener">University of Chicago</a> have now traced high‑level judgment back to the same circuit that pilots a reflexive gaze. 



<a href="https://neurobiology.uchicago.edu/faculty/david-freedman-phd" target="_blank" rel="noreferrer noopener">David Freedman</a>, professor of neurobiology at the university, says the discovery redraws some of the most familiar maps of the mind.



<h2 class="wp-block-heading" id="h-collicular-midbrain-hub-is-ancient">Collicular midbrain hub is ancient</h2>



The <a href="https://pmc.ncbi.nlm.nih.gov/articles/PMC10115501/" target="_blank" rel="noreferrer noopener">superior colliculus</a> sits just above the brainstem and appears in fish, birds, and mammals alike, hinting at an ancestry stretching half a billion years. 



Its layered tissue forms a two‑dimensional grid that rapidly transforms flashes of light into head and eye movements.



For decades, textbooks described the structure as a simple switchboard for <a href="https://www.ncbi.nlm.nih.gov/books/NBK10991/" target="_blank" rel="noreferrer noopener">saccades</a>, the rapid jumps that refresh a scene several times a second. The cortex, by contrast, was said to handle every higher act, from object recognition to chess.



Growing evidence counters that neat divide. A 2017 <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5752317/" target="_blank" rel="noreferrer noopener">review</a> chronicled how collicular neurons encode attention and decision signals once thought exclusive to the cerebral mantle.



Those hints set the stage for a closer look at the midbrain in real time. Freedman’s group answered with electrodes and a clever behavioral trick.



<h2 class="wp-block-heading" id="h-gazing-and-judging">Gazing and judging</h2>



They trained two <a href="https://neprimateconservancy.org/rhesus-macaque/" target="_blank" rel="noreferrer noopener">Macaca mulatta monkeys</a> to hold their eyes on a central point while labeling drifting dot patterns as belonging to one of two learned categories. Fruit‑juice rewards encouraged fast, accurate button presses rather than eye shifts.



During the task, arrays of fine wires captured spikes in the <a href="https://www.sciencedirect.com/topics/neuroscience/posterior-parietal-cortex" target="_blank" rel="noreferrer noopener">posterior parietal cortex</a>, a well‑known decision center, and simultaneously inside the colliculus. 



Timing analysis revealed that category information emerged in both places at almost the same moment.



More surprising, the midbrain signal was stronger and more consistent than the cortical one, indexing the upcoming choice with remarkable fidelity. That meant the ancient hub was not just echoing the cortex but <a href="https://www.nature.com/articles/s41593-024-01744-x" target="_blank" rel="noreferrer noopener">leading</a> the conversation.



“This is a really surprising place to find these kinds of cognitive signals because this area of the brain is traditionally associated with simpler <a href="https://www.earth.com/news/male-and-female-brains-are-wired-completely-differently/">spatial orienting behaviors</a> and even reflexive functions,” said Freedman. He notes that the finding challenges a long‑held hierarchy that placed the <a href="https://www.sciencedirect.com/topics/psychology/neocortex" target="_blank" rel="noreferrer noopener">neocortex</a> firmly on top.



<h2 class="wp-block-heading" id="h-switching-off-the-collicular-midbrain">Switching off the collicular midbrain</h2>



Correlation, however, does not guarantee causation. To probe necessity, the team injected minute doses of muscimol to silence collicular <a href="https://www.earth.com/news/rebooting-the-brain-experts-can-transform-cells-into-neurons/">neurons</a> for about 30 minutes.



The monkeys still stared at the fixation point and pushed buttons with normal speed, showing that motor paths remained largely intact. Even so, their category judgments slipped toward chance until normal firing returned.



A 2021 <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8338902/" target="_blank" rel="noreferrer noopener">study</a> by Michele Basso and colleagues had already shown that damping the same region biases simpler motion decisions in primates. The new work extends that causal role to abstract rules untied to any spatial cue.



“Our results show us that this area is really important for the task,” Freedman added. Without its input, the cortex alone could not salvage performance.



<h2 class="wp-block-heading" id="h-collicular-neurons-and-spatial-maps">Collicular neurons and spatial maps</h2>



The collicular sheet represents space in a neat polar grid, each <a href="https://www.earth.com/news/cell-division-discovery-challenges-a-century-of-textbook-biology/">cell</a> preferring a particular direction and eccentricity. Such organization may offer high‑speed scaffolding for loftier computations.



Freedman suspects that the brain projects non‑spatial information onto that grid to exploit wiring already optimized for rapid competition among options. 



Spatial coding could act as a common currency, letting disparate sensory and memory traces jostle under a single rulebook.



Separate teams have found midbrain <a href="https://www.sciencedirect.com/science/article/pii/S0896627324004124" target="_blank" rel="noreferrer noopener">neurons</a> that single out faces mere milliseconds after stimulus onset, bypassing the slower ventral stream. 



Others report <a href="https://pubmed.ncbi.nlm.nih.gov/37352857/" target="_blank" rel="noreferrer noopener">collicular bursts</a> that end deliberations once evidence reaches a threshold, acting like an internal referee.



“Some of this data might be telling us that the spatial parts of the brain are getting recruited into helping us perform these non-spatial cognitive functions,” said <a href="https://scholar.google.com/citations?user=em1qF1AAAAAJ&amp;hl=en" target="_blank" rel="noreferrer noopener">Barbara Peysakhovich</a>, first author of the study. Her remark underscores how evolution can co‑opt one circuit for many jobs.



<h2 class="wp-block-heading" id="h-midbrain-collicular-circuits-and-perception">Midbrain collicular circuits and perception</h2>



Functional MRI supports the idea in humans. Activity flares in the colliculus when volunteers search <a href="https://bmcneurosci.biomedcentral.com/articles/10.1186/1471-2202-8-66" target="_blank" rel="noreferrer noopener">cluttered scenes</a> or shift attention without moving their eyes.



A <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4949391/" target="_blank" rel="noreferrer noopener">study</a> that probed eye‑driven Go/No‑Go decisions in progressive supranuclear palsy linked slow saccades to impaired evidence accumulation, implicating the same midbrain route. 



Such overlap suggests that eye‑movement disorders and cognitive decline may share a single lesion site.



Computational neuroscientists are now modeling collicular circuits to design cameras that spot hazards before full scene analysis is complete. The Chicago data offer a fresh template for those algorithms.



Ultimately, the study blurs a tidy border between perception and reflection. It invites a broader search for additional double‑duty nodes throughout the <a href="https://www.earth.com/news/big-changes-in-the-brain-between-the-ages-of-11-25-and-how-it-influence-our-decisions/">brain</a>.



<h2 class="wp-block-heading" id="h-next-steps-and-implications">Next steps and implications</h2>



Freedman plans to test whether similar signals appear in people using magnetoencephalography combined with deep‑brain electrical recordings during surgery. Such work could clarify how much of the primate finding generalizes to everyday human reasoning.



Another priority is mapping the pathways that carry the category code into and out of the midbrain. Anatomical <a href="https://pmc.ncbi.nlm.nih.gov/articles/PMC10115501/" target="_blank" rel="noreferrer noopener">studies</a> already show dense links from frontal <a href="https://www.earth.com/news/unexpected-find-inside-the-eye-of-a-tiny-wasp-megaphragma-viggianii/">eye</a> field to colliculus as well as ascending fibers that reach the cortex via the thalamus.



Untangling those loops may reveal how a single decision circulates between brainstem and cortex <a href="https://www.earth.com/news/action-observation-network-human-brain-perception-see-what-we-expect-to-see-mind-eye/">before reaching awareness</a>. The results could also help clinicians fine‑tune deep‑brain stimulators aimed at restoring gaze and cognition in movement disorders.



The study is published in <a href="https://www.nature.com/articles/s41593-024-01744-x" target="_blank" rel="noreferrer noopener">Nature Neuroscience</a>.



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Humans use the same ancient midbrain circuits for both seeing and thinking, says a new study

Every fleeting glance you take of your surroundings sets off...

Some imported seafoods on American dinner plates are carrying an invisible threat: bacteria equipped with genes that can disarm a high-priority, critically important antibiotic called colistin.



Colistin is reserved for life-threatening infections that have outwitted every other drug. When it fails, clinicians have nowhere left to turn.



In research presented at <a href="https://asm.org/events/asm-microbe/home">ASM Microbe 2025</a>, scientists at the <a href="https://www.uga.edu/">University of Georgia</a> found colistin-resistance genes - known as mcr - in <a href="https://www.earth.com/news/shrimp-crisis-alarming-virus-threatens-global-seafood-supplies/">shrimp</a> and scallops purchased from eight Atlanta-area grocery stores.



It is the first evidence that U.S. seafood shoppers are unknowingly buying products harboring bacteria capable of shrugging off one of medicine’s last lines of defense.



<h2 class="wp-block-heading" id="h-seafood-s-global-supply-chain">Seafood's global supply chain</h2>



Lead investigator Issmat Kassem has spent two decades tracing the global spread of <a href="https://www.earth.com/news/genes-for-antibiotic-resistance-lurk-in-our-wastewater-and-streams/">antimicrobial resistance</a>.



Sampling from local supermarkets, his team ran genetic screens on bacteria living in the imported seafood including shellfish and uncovered multiple plasmids - circular snippets of DNA - that carry mcr.



These plasmids make resistance “mobile,” because the genes can hop from one bacterium to another.



When Kassem talks about the popular appeal of shellfish, he puts it simply: “We love our seafood.”



And most Americans do: about 90 percent of the shrimp consumed in the United States are raised overseas. Many exporting nations still rely on antibiotics, including colistin, to treat or fatten farmed animals.



That practice creates selective pressure for resistant <a href="https://www.earth.com/news/some-bacteria-breathe-by-creating-electricity/">bacteria</a>, which can end up in packing plants, shipping containers, and ultimately U.S. kitchens.



<h2 class="wp-block-heading" id="h-the-last-resort-antibiotic">The last-resort antibiotic</h2>



Colistin debuted in the 1950s, then largely disappeared from U.S. hospitals because it can scar kidneys and nerves. Its toxic profile forced doctors to shelve it in favor of safer drugs.



That calculus reversed when so-called “superbugs” evolved resistance to nearly every other antibiotic. Colistin returned as a last resort, but its revival was overshadowed by news in 2016 of the first plasmid-borne mcr gene.



Until then, many scientists assumed colistin resistance evolved only through slow, vertical inheritance. The plasmid discovery rewrote that script, proving resistance could not jump between different bacteria - an assumption Kassem now calls dangerously outdated.



Today, at least ten mcr variants have been catalogued worldwide, and Kassem’s new findings reveal a pathway for them to enter U.S. ecosystems.



In earlier work, his lab found the same plasmids and bacterial hosts in Georgia wastewater. The match confirms that agricultural practices abroad can shape microbial landscapes at home.



<h2 class="wp-block-heading" id="h-a-supply-chain-problem"><a></a>A supply chain problem</h2>



Although federal inspectors test imported seafood for chemical residues and visible pathogens, they do not routinely test for resistance genes.



“The bacteria that were carrying colistin resistance genes are not normally screened,” Kassem warned. Standard checks, designed decades ago, fail to catch this genomic stowaway.



“Our food is sourced from different places,” he said. “If you go out to lunch today, your plate might have ingredients from six, seven, eight countries.” These complex supply chains enable a hidden circulation of microbes.



“Some countries do not have strict regulations for using antibiotics in food animal production, so imported food can be a vehicle for transmission of resistance.”



Domestic aquaculture operations appear free of mcr for now, suggesting U.S. oversight can be effective when consistently applied.



<h2 class="wp-block-heading" id="h-no-borders-for-seafood-superbugs">No borders for seafood "superbugs"</h2>



Resistance that travels by plasmid does not respect borders. “We live in a very connected world,” Kassem emphasized.



“We move a lot, we travel a lot, our food travels, and we are going to spread whatever emerges, even across national borders.” In other words, the United States cannot isolate itself from a problem embedded in international trade.



That reality underscores the need for better surveillance. “It’s important to invest in monitoring systems and expand them and collaborate, especially on the global level, on the issue of antimicrobial resistance,” Kassem said.



Enhanced screening at ports of entry could catch resistant bacteria before they enter the consumer market. Equally critical is global cooperation to reduce unnecessary antibiotic use in aquaculture and <a href="https://www.earth.com/news/bacteria-in-livestock-are-major-drivers-of-antibiotic-resistance/">livestock</a> production.



<h2 class="wp-block-heading" id="h-hidden-risks-in-the-kitchen">Hidden risks in the kitchen</h2>



Cooking <a href="https://www.earth.com/news/shellfish-waste-can-be-used-for-fresher-safer-produce/">shellfish</a> thoroughly destroys live bacteria, but plasmid DNA may survive and flow into wastewater systems.



Consumers should handle raw imported seafood with the same caution they would raw poultry. This includes washing hands, sanitizing cutting boards, and avoiding cross-contamination with ready-to-eat foods. Yet individual diligence cannot solve a systemic problem.



The study shows that antimicrobial resistance is no longer confined to hospitals or far-off farms - it can ride quietly into suburban kitchens on ice. 



<h2 class="wp-block-heading" id="h-a-global-health-warning">A global health warning</h2>



If policymakers act swiftly, the United States can reinforce its defenses by updating import regulations and requiring genetic testing for high-risk resistance genes. It can also partner with exporting nations to curb antibiotic misuse.



For now, Kassem’s message is a wake-up call. Colistin remains a critical, if imperfect, guardian against multidrug-resistant infections.



Allowing its defenses to erode - even incrementally - brings the world closer to a post-antibiotic era where routine surgeries and minor wounds become life-threatening. 



The microbes in our seafood are sending a warning. Whether we heed it will shape the future of <a href="https://www.earth.com/news/antibiotic-resistance-could-cause-a-health-crisis-globally/">global health</a>.



The study is published in the journal <a href="https://journals.asm.org/journal/msphere">mSphere</a>.



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Imported seafood is spreading antibiotic resistance genes

Some imported seafoods on American dinner plates are carrying an...

Scientists recently discovered that certain changes in the roots of teeth can reveal whether someone is a current or former smoker. 



This breakthrough came from a team at <a href="https://www.northumbria.ac.uk/" target="_blank" rel="noreferrer noopener">Northumbria University</a>, working alongside scientists from the <a href="https://le.ac.uk/" target="_blank" rel="noreferrer noopener">University of Leicester</a>. Their findings could offer powerful tools for both forensic science and archaeology.



<h2 class="wp-block-heading" id="h-what-teeth-can-tell-us">What teeth can tell us</h2>



Your teeth aren’t just for chewing. They carry a hidden timeline of your life. Teeth are made up of <a href="https://www.earth.com/news/tooth-enamel-holds-a-record-of-human-health/">enamel</a>, dentine, and cementum. 



<a href="https://www.sciencedirect.com/topics/medicine-and-dentistry/cementum" target="_blank" rel="noreferrer noopener">Cementum</a> is the hard tissue that coats the tooth’s root, and it grows in layers - similar to the way trees deposit annual growth rings. Every year, a new layer forms.



The research team originally set out to use these cementum rings to estimate a person’s age. That kind of analysis can help identify victims of disasters when DNA samples aren’t available.



“By looking at <a href="https://www.earth.com/news/tree-rings-reveal-the-carbon-storage-capacity-of-a-forest/">growth rings</a> in the teeth, we can also estimate a person’s age when the tooth was removed, or when they died,” said Dr. Ed Schwalbe, coauthor and professor in the Faculty of Health and Life Sciences at Northumbria University.



“Together, this information could help identify unknown individuals - such as disaster victims or those buried in mass graves - and offer new tools for forensic and historical investigations,” he confirmed.



But they also found something unexpected.



<h2 class="wp-block-heading" id="h-smoking-marks-teeth-as-well">Smoking marks teeth as well</h2>



They examined 88 teeth from both living dental patients and archaeological remains. In many cases, the cementum rings weren’t smooth and regular. Some had disruptions - changes in thickness or shape that didn’t line up with the typical growth pattern.



They looked more closely. These disruptions weren’t random. They were consistently found in the teeth of people who smoked or used to smoke.



“Our research shows that it’s possible to tell if someone was a smoker just by examining their teeth,” said Dr. Schwalbe. 



“We found that the regular annual deposition of rings was disrupted for some individuals and realised that these disruptions were associated with current or ex-smokers, but were very rare in non-smokers.”



<h2 class="wp-block-heading" id="h-smoking-s-undeniable-signature-in-teeth">Smoking's undeniable signature in teeth</h2>



In teeth from former <a href="https://www.earth.com/news/smokers-have-weaker-hearts-that-pump-less-blood/">smokers</a>, the team saw thick layers of cementum built up over disrupted rings. They believe that when someone quits <a href="https://www.earth.com/news/quitting-smoking-at-any-age-brings-big-and-immediate-health-benefits/">smoking</a>, the cementum begins to return to a normal growth pattern, forming denser layers on top of the older, damaged ones. 



That may explain why ex-smokers’ teeth showed thicker cementum than was found in the teeth of current smokers.



The numbers were striking. Disrupted cementum appeared in 70% of ex-smokers and 33% of current smokers - but in only 3% of people who had never smoked.



<figure class="wp-block-image aligncenter size-full"><a href="https://www.earth.com/wp-content/uploads/2025/06/smoking_teeth-stains-damage_cementum-rings_credit-NorthumbriaU_1m.jpg"><img src="https://www.earth.com/wp-content/uploads/2025/06/smoking_teeth-stains-damage_cementum-rings_credit-NorthumbriaU_1s.webp" alt="Example of smoking damage in an archaeological tooth. The magnified image shows variations in the tooth's cementum rings from smoking. Credit: Northumbria University" class="wp-image-1975125"/></a><figcaption class="wp-element-caption">Example of smoking damage in an archaeological tooth. The magnified image shows variations in the tooth's cementum rings from smoking. Click image to enlarge. Credit: Northumbria University</figcaption></figure>



“We compared the cemental deposition of smokers, ex-smokers and non-smokers visually and statistically to identify irregularities that were potentially connected to smoking activity,” said Dr. Valentina Perrone, lead author on the study. 



“We found that individuals with a history of smoking - whether as a current or former smoker – were significantly more likely to have disruption to their cementum than those who did not."



<h2 class="wp-block-heading" id="h-quitting-doesn-t-remove-smoking-markers">Quitting doesn't remove smoking markers</h2>



The study included 46 living participants who needed teeth extracted as part of routine <a href="https://www.earth.com/news/brushing-your-teeth-regularly-can-prevent-deadly-liver-disease/">dental care</a>. In one standout case, a participant’s tooth showed damage estimated to have occurred between the ages of 22 and 41.



When the researchers reviewed the patient’s history, they found that the individual, who was aged 58 at the time, had smoked between the ages of 28 and 38.



That matched the evidence exactly.



“Smoking is known to have a systemic impact on the body and numerous studies have highlighted the correlation between smoking, <a href="https://www.mayoclinic.org/diseases-conditions/periodontitis/symptoms-causes/syc-20354473" target="_blank" rel="noreferrer noopener">periodontitis</a> and tooth loss,” Dr Perrone added. 



“This study shows, for the first time, the biological record of smoking-related oral health damage within the dental structure.”



<h2 class="wp-block-heading" id="h-echoes-from-past-centuries">Echoes from past centuries</h2>



To test whether these markers of smoking could be found in much older remains, the team worked with Dr. Sarah Inskip, UKRI Fellow at the University of Leicester’s School of Archaeology and Ancient History. They examined 18 archaeological teeth dating from between 1776 and 1890.



Some of these teeth came from individuals known to have smoked. Signs included discoloration and even physical notches worn into the teeth by clay pipes.



Even after centuries underground, the cementum in those teeth still bore the same disruption patterns as found in the teeth of modern smokers.



“This could help us learn more about people’s lifestyles in the past, especially in archaeological studies where patterns of <a href="https://www.earth.com/news/tobacco-bans-could-help-prevent-1-2-million-lung-cancer-deaths/">tobacco</a> use can reveal important cultural insights,” said Dr. Schwalbe.



“The identification of 'smoking damage' in archaeological teeth opens up further avenues to understand how the long-term consumption of tobacco in populations has affected our health through time,” Dr. Inskip added.



<h2 class="wp-block-heading" id="h-your-teeth-don-t-lie">Your teeth don’t lie</h2>



These findings show that even if someone quits smoking, their teeth may carry the evidence for life. 



That insight has major implications - not just for understanding personal health histories, but for reconstructing the lives of people long gone.



The next time you smile, remember that your teeth are holding a history of some of your lifestyle choices.



The full study was published in the journal <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0323812" target="_blank" rel="noreferrer noopener">PLOS One</a>.



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Smoking leaves permanent traces in teeth deep below the surface - a new forensic

Scientists recently discovered that certain changes in the roots of...

A potential single-dose vaccine might be closer than we think. Scientists say it could one day protect against viruses like HIV or COVID-19 without the need for repeat shots. 



The secret? Pairing two immune-boosting ingredients - called adjuvants - in the same formula.



In a recent study with mice, researchers from the Massachusetts Institute of Technology (<a href="https://www.mit.edu/" target="_blank" rel="noreferrer noopener">MIT</a>) and the <a href="https://www.scripps.edu/" target="_blank" rel="noreferrer noopener">Scripps Research Institute</a> showed how this dual-adjuvant strategy triggered a much broader immune response than standard vaccines. 



The mix helped the body produce a wider variety of antibodies, offering stronger, longer-lasting protection from <a href="https://www.earth.com/news/mild-obesity-linked-to-greater-risk-of-severe-covid-19-infection/">infection</a>.



<h2 class="wp-block-heading" id="h-adjuvants-matter-in-single-dose-vaccines">Adjuvants matter in single-dose vaccines</h2>



Adjuvants are added to many vaccines to help fire up the immune system. They don’t act on the virus directly, but they do help your body learn to recognize and fight it. 



One common adjuvant is alum (aluminum hydroxide), and it is used in vaccines for <a href="https://www.earth.com/news/mysterious-cases-of-hepatitis-detected-in-the-us-and-europe/">hepatitis</a> A and B. It boosts the immune system by activating the body’s first line of defense.



Years ago, scientists at Scripps created another adjuvant using saponin, a compound from the bark of the Chilean <a href="https://www.earth.com/news/soap-bark-tree-discovery-could-revolutionize-vaccine-production/">soapbark tree</a>. 



This adjuvant, when packaged into tiny particles, along with another immune stimulator (MPLA), showed even better results.



That combo, known as SMNP, is already being tested in an HIV vaccine in human trials.



The team decided to test what would happen if they combined alum and SMNP in a single-dose vaccine. The result? An even more powerful immune response against both HIV and SARS-CoV-2.



<h2 class="wp-block-heading" id="h-single-dose-vaccine-sticks-around">Single-dose vaccine sticks around</h2>



For the new study, researchers focused on how these two adjuvants work together. They used a protein from <a href="https://www.earth.com/news/genetic-variant-linked-to-both-covid-risk-and-hiv-protection/">HIV</a> called MD39 as their target and stuck dozens of these proteins to alum particles, along with SMNP.



When injected into mice, this enhanced vaccine headed straight for the lymph nodes. These small structures are where immune cells, like B cells, train to recognize invaders. 



Inside the lymph nodes, B cells mutate rapidly to make stronger, more precise <a href="https://www.earth.com/news/human-antibodies-are-adapting-to-fight-emerging-covid-variants/">antibodies</a>. This training happens in special clusters called germinal centers.



The scientists found that their vaccine was able to slip through the protective shell around the lymph nodes and stay intact. It remained inside for almost a month - a long time in immune system terms. That allowed B cells to keep working and improving their antibody response.



“As a result, the B cells that are cycling in the lymph nodes are constantly being exposed to the antigen over that time period, and they get the chance to refine their solution to the antigen,” said J. Christopher Love,&nbsp;the Raymond A. and Helen E. St. Laurent Professor of Chemical Engineering at MIT. 



<h2 class="wp-block-heading" id="h-wider-arsenal-of-antibodies">Wider arsenal of antibodies</h2>



To understand the impact, the team used single-cell RNA sequencing to analyze the B cells from the vaccinated mice. 



The group that received both adjuvants in a single-dose vaccine showed a much more diverse set of B cells and antibodies.



They had two to three times more unique B cells than mice that got just one <a href="https://www.earth.com/news/plant-based-covid-vaccine-is-safe-and-effective/">adjuvant</a>.



That matters. The more diverse the antibodies, the better the chances of being effective against different strains of a virus, like HIV, that mutates constantly.



“When you think about the immune system sampling all of the possible solutions, the more chances we give it to identify an effective solution, the better,” Love explained. 



“Generating broadly neutralizing antibodies is something that likely requires both the kind of approach that we showed here, to get that strong and diversified response, as well as antigen design to get the right part of the immunogen shown,” he added.



<h2 class="wp-block-heading" id="h-toward-a-one-and-done-vaccine">Toward a one-and-done vaccine</h2>



This approach could simplify vaccine schedules. Instead of needing multiple doses, a single shot might be enough.



“What’s potentially powerful about this approach is that you can achieve long-term exposures based on a combination of adjuvants that are already reasonably well-understood, so it doesn’t require a different technology. It’s just combining features of these adjuvants to enable low-dose or potentially even single-dose treatments,” Love concluded.



The research points to a future of smarter vaccines - and fewer needles.



The full study was published in the journal <a href="https://www.science.org/doi/10.1126/scitranslmed.adw7499" target="_blank" rel="noreferrer noopener">Science Translational Medicine</a>.



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A smarter shot: Scientists explore single-dose vaccine power

A potential single-dose vaccine might be closer than we think....

Scientists are transforming chocolate into a functional food by infusing it with probiotics and prebiotics, aiming to create a treat that satisfies cravings while supporting gut health. 



The challenge lies in maintaining chocolate's beloved texture and flavor while adding health benefits.



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https://youtu.be/Ug657J67iEo?si=w96YjGMsg939LD_3
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Probiotics - beneficial microbes that balance gut bacteria and aid digestion - are typically fragile and can be destroyed by stomach acid or processing. 



Prebiotics act as food for these microbes, helping them thrive. Together, they form "synbiotics," a powerful health combination.



Researchers Smriti Gaur and Shubhi Singh from India's Jaypee Institute of Information Technology took an innovative approach, using natural prebiotics like corn and honey instead of complex processing methods. 



They created five chocolate varieties: a control and four synbiotic versions containing different combinations of prebiotics, probiotics (Lactobacillus strains), and flavor enhancers (cinnamon or orange).



Laboratory simulations of human digestion showed the probiotics remained viable for over five hours, suggesting they could survive long enough to benefit gut health.



Taste tests were positive, with researchers particularly enjoying the orange-flavored variety, describing it as having "vibrant citrus notes" complementing the "rich cocoa" with a "luxurious" texture.



This research represents just the beginning. With further refinement of strains, textures, and flavors, chocolate could evolve beyond mere indulgence to become a functional food that nourishes while it delights.



The study is published in the journal <a href="https://pubs.acs.org/doi/10.1021/acsfoodscitech.4c00741" target="_blank" rel="noreferrer noopener">ACS Food Science &amp; Technology</a>.

Is chocolate the next nutritional powerhouse?

Scientists are transforming chocolate into a functional food by infusing...

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Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features Nushagak Bay, a large estuary in southwest Alaska. Nushagak runs mainly north to south and exits in Bristol Bay, a large body of water in the Bering Sea.



"The bay is primarily fed by the Nushagak River, which begins in the Alaska Range and flows southwest approximately 450 km. The bay is also fed by several additional rivers including the Wood, Igushik, Snake and Weary rivers," says ESA.



"The dark colors of the Nushagak River are most likely due to tannins or lignins (chemical substances found in plants). Tannins and lignins from roots, leaves, seeds, bark and soil can leach into the water and give it a brown or even black colour. The sediments then flow southwards where it is mixed with the bluer waters of the bay."



Video/ Image Credit: ESA



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By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Nushagak Bay in southwest Alaska

[sendtonews key="0ynNMYkMKa-2340414-12187" type="single"] Today’s Video of the Day from the...

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Today's Video of the Day from the <a href="https://www.acs.org/">American Chemical Society</a> (ACS) reveals that proteins on flu viruses are actually flexible, tilting and waving in a “breath-like” motion. According to the experts, these proteins could be used to better defend against the flu.



"The main antigenic targets of influenza virus are two surface glycoproteins, hemagglutinin (HA) and neuraminidase (NA). Whereas the structural and dynamical properties of both glycoproteins have been studied previously, the understanding of their plasticity in the whole-virion context is fragmented," wrote the researchers.



To investigate, the team conducted detailed simulations of the influenza A H1N1 virion, or the swine flu. The experts concluded that the visualizations show many new vulnerable states of flu viruses, which could improve future vaccines and antiviral drugs.



Video/ Image Credit: American Chemical Society&nbsp;



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



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Flu viruses are more flexible than expected

[sendtonews key="G9bUoxcjr4-2511624-12187" type="single"] Today's Video of the Day from the...

Hubble reveals a black hole hidden in a distant galaxy

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