Today's Image of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> features the Messina Strait, a channel in the Mediterranean Sea that separates Sicily and Calabria. The photograph was captured by an astronaut onboard the International Space Station



The Messina Strait is 20 miles long with a depth of 820 feet, and joins the Tyrrhenian Sea to the north and the Ionian Sea to the south.&nbsp;



"Waves that follow the tide from west to east are visible in the right half of the photo. These are caused by internal waves, a process where stratified water layers of changing density and increasing depth horizontally propagate beneath the water surface. The waves are illuminated by sunglint—an optical phenomenon that occurs when sunlight is directly reflected off the water and into a satellite’s sensor, or in this case, the astronaut’s camera," explains NASA.



"Alternating currents, relatively low water temperature, and high levels of phosphorus and nitrogen contribute to the region’s aquatic biodiversity. The strait hosts several deep-sea fish species such as Sloane’s viperfish (a predatory dragonfish) as well as commercially valuable fish like yellowtail and snapper. On the left side of the image, thin, white lines are likely ship wakes, some of which may belong to fishing boats."



Image Credit: NASA Earth Observatory&nbsp;



---



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



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

Messina Strait in the Mediterranean Sea

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

Today's Image of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> features an astronaut photograph of the Amazon River in Brazil. This particular stretch of river is located near the port city of Parintins.



"The river is the largest on Earth and allows seagoing ships to reach Parintins even though it is 800 kilometers (500 miles) inland from the Atlantic Ocean," says NASA.



"Seagoing ships can progress 3,600 kilometers (2,200 miles) up the Amazon River - more than halfway across the South American continent - to the port of Iquitos in Peru."&nbsp;



The muddy color of the river is tied to the Andes Mountains, a major source of sediments and mineral nutrients. According to NASA, the sediment erodes from the Andes Mountains located to the west and is carried generally eastward toward the ocean.&nbsp;



Image Credit: NASA Earth Observatory&nbsp;



---



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



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

The lower Amazon River in Brazil

Today's Image of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> features an astronaut photograph of the Espíritu Santo Archipelago, a group of islands located in the Gulf of California, also known as the Sea of Cortez, off the eastern coast of the Baja California Peninsula in Mexico.&nbsp;



"Sunglint reflects off the water surface, accentuating wave movement, ship wakes, and cloud shadows," said NASA. "The islands appear rust-colored due to previous tectonic and volcanic activity that deposited layers of black lava and pink volcanic ash."



"The Baja Peninsula acts as a natural wind and wave break that protects islands in the Gulf of California from erosion. Slowed erosion has resulted in the preservation of rock shelters and caves."



"Exploration and excavation of these shelters contribute to understanding the geomorphology, geology, and ancient human patterns on the islands. Archeologists have found human artifacts artifacts dating back approximately ten thousand years, providing evidence of human activity on the islands."



The Espíritu Santo Archipelago is part of the Mexican state of Baja California Sur and consists of several islands, the largest and most well-known of which is Isla Espíritu Santo. The other main islands in the archipelago are Isla Partida, Los Islotes, and a few smaller islets.



Espíritu Santo and its surrounding islands are known for their stunning natural beauty, featuring dramatic cliffs, white sand beaches, and turquoise waters. The region is home to a rich diversity of marine life, including sea lions, manta rays, whale sharks, and various species of whales and dolphins. It also supports a variety of bird species, such as blue-footed boobies, frigatebirds, and pelicans, making it a popular destination for birdwatching.



The Espíritu Santo Archipelago has been designated a UNESCO Biosphere Reserve and a Mexican Protected Natural Area, which helps to preserve its unique ecosystems and biodiversity. Ecotourism is popular in the area, with visitors participating in activities like snorkeling, scuba diving, kayaking, and wildlife watching.



The islands are accessible by boat from the nearby city of La Paz, which is the capital of Baja California Sur. There are numerous tour operators that offer day trips and multi-day excursions to the Espíritu Santo Archipelago, allowing visitors to explore the islands and their remarkable natural features.



Image Credit: NASA Earth Observatory&nbsp;



---



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



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

Espíritu Santo Archipelago in the Gulf of California

Today's Image of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> features the Dark Canyon Complex, which is a rugged, remote area in southeastern Utah. It's part of the larger Cedar Mesa Plateau and includes both the Dark Canyon Wilderness and Dark Canyon Primitive Area.&nbsp;



These are areas of steep canyons, high plateaus, and rock formations that are characteristic of the Colorado Plateau.



"Deep, meandering canyons cut through the Colorado Plateau in southeastern Utah in this photograph, taken by an astronaut on the International Space Station on April 6, 2023," says NASA.



"These canyons, known as the Dark Canyon complex, have distinctive geology, ecology, and archeology. They are some of the only intact protected canyons in the United States."



"This rugged and remote landscape has been shaped by erosion. Over thousands of years, the Colorado River and smaller tributaries have eroded winding, steep-walled canyons into the sedimentary rock. Dark Canyon - one of seven canyons within the complex - cuts diagonally across the photo."



"Within this canyon, sandstone walls tower up to 3,000 feet, shading visitors from morning and afternoon sun - hence its name. The canyon’s steep walls expose roughly 250 million years of geologic history and contain deposits from the Permian period. Cockleshell and crinoid stem fossils have been found in the area."



The astronaut photograph is provided by the ISS Crew Earth Observations Facility and the Earth Science and Remote Sensing Unit, Johnson Space Center. The image was taken by a member of the Expedition 69 crew.&nbsp;



Image Credit: NASA Earth Observatory&nbsp;



---



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



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

The Dark Canyon Complex in southeastern Utah

Today's Image of the Day from the <a href="https://www.esa.int/">European Space Agency </a>&nbsp;features Seoul, the capital city of South Korea, and its surroundings. The image was captured by the Copernicus Sentinel-2 mission on February 21, 2023.



"Situated some 50 km south of the North Korean border, the metropolitan area of Seoul appears as the grey area in the centre of the image," says ESA.



"The Han River runs through the city, and to the right of the image it can be seen partly covered by ice. It is one of the biggest rivers in the Korean peninsula. It flows westward through Seoul into the Yellow Sea, named so because of the yellowish sand that colours its water."



"Seoul is surrounded by forested mountains, which appear brown in this wintery image. Bukhansan National Park lies just north of the city. The park is like an island, acting as a big green lung for the surrounding urban environment."



Image Credit: ESA&nbsp;



---



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



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

The city of Seoul, South Korea 

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

A groundbreaking study conducted by the <a href="https://www.umd.edu/">University of Maryland</a> School of Public Health has revealed the remarkable benefits of regular <a href="https://www.earth.com/news/exercise-may-actually-be-the-fountain-of-youth/">exercise</a>, specifically walking, for the health of our brain. According to the researchers, the positive cognitive impacts of walking are especially noticeable in older adults.&nbsp;



The study unveiled how this simple, low-impact physical activity can fortify connections within three pivotal brain networks, including one associated with Alzheimer's disease. This discovery adds a significant dimension to a growing collection of evidence which confirms the powerful role of regular exercise in promoting brain health and delaying the onset of cognitive decline.



The study, recently published in the <a href="http://dx.doi.org/10.3233/ADR-220062">Journal for Alzheimer's Disease Reports</a>, scrutinized the narrative recall abilities of older adults who have been diagnosed with mild cognitive impairment (MCI), as well as those with normal brain function. MCI is characterized by a mild decline in mental faculties such as memory, reasoning, and judgment, and is considered a risk factor for Alzheimer's.



Professor J. Carson Smith, the study's principal investigator, explained: "Historically, the brain networks we studied in this research show deterioration over time in people with mild cognitive impairment and Alzheimer's disease. They become disconnected, and as a result, people lose their ability to think clearly and remember things. We're demonstrating that exercise training strengthens these connections."&nbsp;



Professor Smith's previous studies have also suggested that walking can reduce cerebral blood flow and improve brain functionality in older adults diagnosed with MCI.



In this new study, thirty-three participants, aged between 71 and 85, were asked to walk on a treadmill under supervision for four days a week over a period of 12 weeks. Prior to and beyond this exercise regimen, the researchers evaluated the participants' recall abilities by asking them to read a short story and then repeat it out loud with as much detail as possible.



In addition to this, the researchers employed functional magnetic resonance imaging (fMRI) to monitor and measure changes in communication within and between the three crucial brain networks responsible for cognitive functions. These networks include:



The default mode network, which activates when a person isn't engaged in a specific task. This network is linked to the hippocampus, a brain region first affected by Alzheimer's, and the first location where Alzheimer's and amyloid plaques appear.



The frontoparietal network, which regulates decisions made when a person is completing a task. This network also plays a role in memory retention.



The salience network, which monitors the external world and stimuli, and determines what requires attention. It also facilitates the transition between networks to optimize performance.



Post 12 weeks of regular walking, the tests were repeated and the researchers observed substantial enhancements in the story recall abilities of the participants.&nbsp;



"The brain activity was stronger and more synchronized, demonstrating exercise actually can induce the brain's ability to change and adapt," noted Professor Smith. "These results provide even more hope that exercise may be useful as a way to prevent or help stabilize people with mild cognitive impairment and maybe, over the long term, delay their conversion to Alzheimer's dementia."



Furthermore, the researchers observed intensified activity within the default mode network, within the salience network, and in the connections between the three networks. This exciting revelation highlights the potential of regular physical activity as a powerful tool to bolster cognitive health and slow the progression of debilitating diseases like Alzheimer's.



<h2 id="h-additional-health-benefits-of-walking">Additional health benefits of walking&nbsp;</h2>



Walking is a simple and accessible form of exercise that offers a plethora of health benefits beyond its positive impact on brain health. Here are some of the additional health advantages of walking:



<h3 id="h-cardiovascular-health">Cardiovascular health</h3>



Regular walking increases the heart rate, strengthens the heart, and enhances overall cardiovascular fitness. Numerous studies have shown that walking reduces the risk of developing cardiovascular diseases, such as heart disease and stroke.



<h3 id="h-blood-pressure-and-cholesterol">Blood pressure and cholesterol</h3>



Walking helps to lower blood pressure and reduce levels of LDL (bad) cholesterol while increasing levels of HDL (good) cholesterol. This leads to improved blood circulation and overall heart health.



<h3 id="h-bone-health">Bone health&nbsp;</h3>



Regular walking, being a weight-bearing exercise, can slow the loss of bone mass for those with osteoporosis. It improves bone density and decreases the risk of fractures.



<h3 id="h-weight-management">Weight management</h3>



Walking burns calories, and thus can contribute to maintaining a healthy weight. It boosts metabolic rate and helps in fat burning, which is crucial for weight management and obesity prevention.



<h3 id="h-muscle-strength-and-endurance">Muscle strength and endurance</h3>



Walking, especially speed walking or walking uphill, can strengthen the leg muscles, improve endurance, and increase flexibility.



<h3 id="h-mental-health">Mental health</h3>



Walking, like other forms of exercise, releases endorphins, often known as "feel-good hormones." This can help to alleviate symptoms of depression and anxiety, boost mood, and promote a sense of well-being.



<h3 id="h-diabetes-management">Diabetes management</h3>



Regular walking has been found to help lower blood sugar levels and overall help in the management of type 2 diabetes.



<h3 id="h-digestion">Digestion</h3>



Regular walking helps improve gastric mobility, aiding the digestive process. It can help prevent constipation and other digestion-related problems.



<h3 id="h-immunity-boost">Immunity boost</h3>



Walking can boost the immune system, leading to a better defense mechanism against various diseases and infections.



<h3 id="h-improved-sleep">Improved sleep</h3>



Walking, especially when done in the morning or afternoon, can help individuals fall asleep more quickly and enjoy better quality sleep.



The beauty of walking is its simplicity and versatility; it requires no special equipment and can be done almost anywhere – around your neighborhood, in parks, on a treadmill, or even while shopping. Incorporating walking into your daily routine can lead to substantial health improvements over time.&nbsp;



—-



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

Walking is a powerful tool to boost brain health and overall well-being

A groundbreaking study conducted by the University of Maryland School...

In a recent study conducted in the lowland rainforests along the Caribbean coast of Costa Rica, researchers have unraveled fascinating details about the behavior and activity patterns of two sympatric sloth species, Bradypus variegatus and Choloepus hoffmanni. These revelations not only shed light on the ecological dynamics of these intriguing creatures, but also highlight their remarkable ability to adapt to a myriad of environmental conditions.



The elusive nature of sloths has historically posed significant challenges to conducting long-term observational research on them. A team led by Dr. Rebecca Cliffe, Founder and Executive Director of <a href="https://slothconservation.org/">The Sloth Conservation Foundation</a>, set out to use micro data loggers to continuously monitor the activities of both three-toed (Bradypus) and two-toed (Choloepus) sloths.&nbsp;



The observation period spanned over days to weeks, which allowed the researchers to explore how these slow-moving <a href="https://www.earth.com/news/what-will-happen-if-modern-large-mammals-become-extinct/">mammals</a> adjusted their activities in response to fluctuating environmental conditions and how such behavior correlated with their unique low-energy lifestyle.



Published in the journal <a href="http://dx.doi.org/10.7717/peerj.15430">PeerJ Life &amp; Environment</a>, the study's findings reveal that both Bradypus and Choloepus sloths display cathemeral activity patterns, which are marked by irregular and variable periods of activity throughout the 24-hour day. This behavior pattern allows the sloths to optimize favorable environmental conditions while minimizing their exposure to predation.



One of the most intriguing findings of this study was the significant variability observed in the activity levels of the sloths. Such flexibility is suggestive of the various strategies these sloths have evolved to adapt to their surroundings, which improves the odds of survival in fluctuating environmental conditions.



Contrary to initial expectations, the researchers found that the daily temperature did not notably influence the sloths' activity. However, the Bradypus sloths displayed an interesting trait: they were more active at night when the temperature dropped, and the nights following colder days saw increased nocturnal activity as well. This observation implies a potential link between temperature variations and the behavioral tendencies of these sloths.



Dr. Cliffe stressed how vital this research is for conservation efforts and for better understanding the repercussions of anthropogenic activities and climate change on the tropical ecosystems of South and Central America. As these ecosystems become increasingly vulnerable, understanding the behavioral ecology of their inhabitants, such as sloths, becomes vital for formulating effective conservation strategies.



The use of micro data loggers in this study has undoubtedly offered unprecedented insights into the behavioral patterns and adaptations of these enigmatic creatures, demonstrating a revolutionary way to investigate the behavioral ecology of elusive species. These findings not only contribute valuable knowledge about sloth ecology, but also underline the importance of preserving and protecting tropical rainforests and their unique inhabitants.



<h2 id="h-more-about-sloths">More about sloths</h2>



Sloths are fascinating creatures that inhabit the tropical rainforests of Central and South America. Belonging to the family Bradypodidae, there are six species of sloths, divided into two groups: the two-toed sloths and the three-toed sloths.



Sloths are arboreal mammals known for their slow movements and unique energy-saving adaptations. These adaptations are part of their survival strategy, as they allow sloths to spend most of their lives in trees, feeding on leaves, twigs, and buds. Their low-energy diet and slow metabolism allow them to conserve energy, which is critical for their survival in resource-poor environments.



One of the most distinctive traits of sloths is their ability to hang from branches with their strong and long claws. This behavior helps protect them from predators like eagles and jaguars. Additionally, sloths are excellent swimmers and can drop from a tree into a river to swim across it.



Sloths have a highly unusual trait: they have the lowest and most variable body temperature of any mammal, ranging from 24 to 33 degrees Celsius. This variability allows them to better regulate their energy usage. Also, sloths only descend from their tree dwellings about once a week to defecate and urinate, a unique behavior among arboreal mammals.



Sloths have a symbiotic relationship with the algae that grow on their fur. The algae provide sloths with camouflage, helping them blend in with the green foliage of their habitat and avoid predators. In return, sloths provide the algae with shelter and water. Additionally, the fur of sloths houses a variety of insects, including beetles and moths.



Sloths are not just slow movers, but they also sleep a lot. Depending on the species, sloths sleep for around 15 to 20 hours a day. This extreme sleep schedule is another energy-saving adaptation.



Conservation efforts are crucial for sloths as they face numerous threats from deforestation, habitat fragmentation, and illegal pet trade. While some sloth species are listed as vulnerable, others, like the critically endangered Pygmy Three-toed Sloth, are on the brink of extinction. Therefore, understanding the behavior and ecological needs of sloths, as demonstrated in the study conducted by Dr. Rebecca Cliffe and her team, is key to ensuring their survival.



—-



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

Study reveals the secret survival strategies of sloths

In a recent study conducted in the lowland rainforests along...

In an era of heightened environmental awareness, a new study has shed light on the complex interplay between food production and biodiversity. The research reveals that our quest to feed the world could inadvertently be driving the loss of biodiversity at an alarming rate.



The study focuses on the environmental footprint of <a href="https://www.earth.com/news/computational-tools-may-improve-the-future-of-farming/">farming</a>, particularly when it comes to food staples like beef, which are notorious for their substantial carbon emissions. Now, new evidence suggests that these same dietary essentials may contribute significantly to the loss of biodiversity.



Study senior author Keiichiro Kanemoto, an associate professor at the <a href="https://www.chikyu.ac.jp/rihn_e/">Research Institute for Humanity and Nature</a> (RIHN) in Kyoto, Japan, noted that, "Food production remains the main cause of biodiversity loss.”



According to the researchers, the problem intensifies when food production encroaches upon areas of high conservation priority. A prevailing issue is the lack of data that could outline which products and countries contribute most to this biodiversity decline.



The researchers set out to bridge this data gap by merging information on agricultural land use and species habitats. They have now identified the agricultural crops exerting the greatest pressure on biodiversity.



The study, published in the <a href="https://www.pnas.org/">Proceedings of the National Academies of Science</a>, ranks commodities based on whether they are sourced from high conservation priority regions. While previous studies have attempted to quantify the carbon, land, and water footprints of the agriculture industry, the threat that farming poses to biodiversity has been less understood, and often overlooked.



The new findings will inform policies designed to strike a balance between preserving biodiversity and maintaining global food security. The research data, encompassing 50 agricultural products sourced from 200 countries, has been made publicly available on Google Earth Engine, a platform often utilized for environmental analyses.



The international research team, with members from Norway, the Netherlands, and Japan, further segmented agricultural areas into four tiers based on their conservation priority. The highest conservation priority was assigned to areas where staple commodities like beef, rice, and soybeans were predominantly produced. Conversely, other staples like barley and wheat were found to be more commonly sourced from areas of lower conservation priority.



Daniel Moran is a senior scientist at the Climate and Environmental Institute NILU and a research professor at the <a href="https://www.ntnu.edu/">Norwegian University of Science and Technology</a>'s (NTNU) Industrial Ecology Programme. “A surprising takeaway for me was how much the impact of the same crop can vary based on where it is sourced from,” said Professor Moran.



The study pointed out striking discrepancies in where certain crops are grown. For example, beef and soybeans are produced in high conservation priority areas in Brazil, but not in North America.



The influence of international trade was also highlighted, as the study revealed the significant role of affluent nations like the US in driving agricultural demand in high conservation priority areas. The research revealed how different nations exhibit vastly different biodiversity food footprints. Countries like the United States, EU, China, and Japan heavily depend on imports to meet their beef and dairy consumption needs.



The researchers also touched on the looming threat of climate change. With rising temperatures projected to alter cropping patterns and available habitats, they used their model to examine future scenarios to understand how the relationship between wild biodiversity and farming might evolve.



The experts predict that as the world grows warmer, species will colonize new territories, potentially opening up fresh high conservation priority areas while mitigating conflicts in existing conservation hotspots.



“Our spatial approach is a valuable complementary method with other standard techniques to evaluate the impact agriculture has on biodiversity. The knowledge gained from our study should help reduce the trade-off many nations associate with agriculture production and environmental protection,” said Kanemoto. “It fills in a big missing piece in the footprint of food.”



“Our lifestyles are causing alarming damage to the atmosphere and water supplies. Farmers and governments worldwide are seeking policies that sustain prosperity while minimizing irreversible harm to the environment. Similar sustainable development policies are needed for agriculture. The calculation of detailed footprints for food and other farmed commodities is crucial to support these policies,” said Professor Moran.



—-



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

Feeding the world at a cost: Food production and biodiversity loss

In an era of heightened environmental awareness, a new study...

<div class="vdb_player vdb_591c9e3c9efa894c3c6e150b58d96b98cd4fed198a0d2a49">
<script src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" type="text/javascript"></script></div>
Sean Sheldrake, a unit dive officer with EPA&#8221;s Region 10, talks about his career at EPA.

EPA Careers: Sean Sheldrake