<p>Today's <strong>Image of the Day</strong> from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> features the largest man-made reservoir in California, Lake Shasta, which filled to nearly 100 percent capacity in May 2023. This is the highest level that Shasta has reached in four years.&nbsp;</p>



<p>"Since 2019, a prolonged period of extreme drought resulted in dwindling reservoir levels. In the early months of 2023, heavy rains and meltwater from an above-average mountain snowpack caused a notable turnaround," said NASA.</p>



<p>"Lake Oroville, the state’s second-largest reservoir, was also near capacity on May 29, at 97 percent full. Both Lake Oroville and Shasta Lake are critical not only for water storage, but also for flood control, recreation, irrigating cropland in the Central Valley, and preventing saltwater intrusion into the Sacramento-San Joaquin Delta."</p>



<p>NASA noted that full reservoirs do not ensure plentiful water for years into the future, and that the past four years are a testament to how drastically reservoirs can change in a short amount of time.&nbsp;</p>



<p>"The California DWR is collaborating with other agencies to incorporate better forecasting and observation technologies in order to optimize water releases."</p>



<p><em>Image Credit: NASA Earth Observatory&nbsp;</em></p>



<p><em>—--</em></p>



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Lake Shasta reaches nearly 100 percent capacity

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

<p>Today's <strong>Image of the Day</strong> from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> features Quebec, where about 160,000 hectares have burned since the start of the year.</p>



<p>"An unusually intense start to Canada’s wildfire season filled skies with smoke in May 2023. Then, at the beginning of June, scores of new fires raged in the central Canadian province of Quebec, some of which were ignited by lightning," says NASA.</p>



<p>"The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite captured this view of smoke billowing from the fires on June 3. Shortly after the fires started, about 5,000 residents were ordered to evacuate near the city of Sept-Îles in the province’s east."&nbsp;</p>



<p>"As the fires grew, evacuations were extended to an additional 9,000 people in surrounding communities and in western Quebec’s Val-d’Or and Normétal municipalities. As of June 5, more than 150 wildfires were active in Quebec."</p>



<p><em>Image Credit: NASA Earth Observatory&nbsp;</em></p>



<p><em>—--</em></p>



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Forest fires rage in Quebec

<p>Today's <strong>Image of the Day</strong> from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> features the west coast of South America. The photo was captured by an astronaut aboard the International Space Station while orbiting over the Atacama Desert and Central Andes Mountains near the border of Bolivia, Peru, and Chile.</p>



<p>"Over the Pacific Ocean, marine stratocumulus clouds develop over cold water that rises from the ocean depths as the Peru current (Humboldt current) flows north along the west coast of South America," says NASA. "The coastline is marked by low mountains that are dissected by canyons carved by rivers that flow down the western side of the Andes."</p>



<p>The Atacama Desert receives less than 0.2 inches of rain per year on average. According to NASA, this dry environment provides an ideal setting to conduct Mars analog studies.</p>



<p>"Active and inactive volcanoes comprise the Central Andean Volcanic Arc within the Atacama Desert and Andes Mountains. One of the inactive volcanoes visible in this photo is Bolivia’s Nevado Sajama, which has a maximum elevation of 6,542 meters (21,463 feet). Nevado Sajama and other volcanoes in the region often have glaciers and snow cover due to their high elevation."</p>



<p><em>Image Credit: NASA Earth Observatory&nbsp;</em></p>



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



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



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The west coast of South America

<p>Today's <strong>Image of the Day</strong> from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> features an astronaut photograph of the Cape Cod peninsula, located in the easternmost portion of Massachusetts. The peninsula extends into the Atlantic Ocean and is a significant feature of the East Coast of the United States.</p>



<p>Cape Cod peninsula is characterized by its beaches, villages, and seafood. It's a popular tourist destination, particularly in the summer months, with people visiting for its beautiful landscapes and unique culture.</p>



<p>Cape Cod consists of 15 towns, including Provincetown, Hyannis, Falmouth, and Chatham. Each town has its own distinctive character and attractions. For example, Provincetown, located at the tip of the peninsula, is known for its vibrant LGBTQ+ scene, while Hyannis is famous as a ferry gateway to the islands of Martha's Vineyard and Nantucket.</p>



<p>The Cape Cod National Seashore, a national park covering much of the Outer Cape, including the entire east-facing coast, provides opportunities for hiking, biking, and beachgoing.</p>



<p>Historically, Cape Cod was a landmark for early explorers of the Americas. It was among the first places settled by the English in North America in the Pilgrim Fathers' era, and it played a key role in the early history and development of the United States.&nbsp;</p>



<p>Today, the Cape's history is preserved in numerous museums, historic sites, and lighthouses. In addition, a variety of wildlife can be found in the region, such as whales, seals, and many species of birds.</p>



<p>"The variety of ecosystems within Cape Cod National Seashore sustain over 450 species of amphibians, reptiles, fish, birds, and mammals, including 32 species that are rare or endangered," says NASA. "One of those species is the American oystercatcher, a large shorebird that uses a knife-like bill to eat shellfish."</p>



<p><em>Image Credit: NASA Earth Observatory&nbsp;</em></p>



<p><em>—--</em></p>



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Cape Cod peninsula in the northeastern United States

<p>Today's <strong>Image of the Day</strong> from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> features the Amundsen Gulf in northern Canada, where ice is typically covered with ice that is fastened to surrounding coastlines. According to NASA, the breakup of this ice tends to be rapid when the melting season arrives in spring.</p>



<p>"Patches of fast ice remained in the eastern part of the gulf in late May, but summer weather will ultimately clear it away as well. The Amundsen Gulf, the western entrance to the Northwest Passage, is usually ice-free by August," says NASA.</p>



<p>Walt Meier, a senior research scientist at the National Snow and Ice Data Center, said that winds play an important role in the breakup of the ice. He noted that an area of low pressure centered south of the gulf prior to the breakup fueled strong easterly winds and large waves that broke up the ice and sent chunks of it drifting west.&nbsp;</p>



<p>This year's spring breakup occurred earlier than usual, which aligns with the overall trend in the Beaufort Sea region in recent decades, noted NASA.</p>



<p>“Over a period of two decades, the Amundsen Gulf had the highest interannual variability of anywhere across the entire Northwest Canadian Arctic,” said Eleanor Wratten, a researcher at Northumbria University and the lead author of an analysis of decades of MODIS observations of fast ice in the Northwest Canadian Arctic.&nbsp;</p>



<p>“We saw the timing of breakup change considerably from one year to the next, but the general pattern looked similar to what you see here. Ice usually remains in the southern bays the longest, with breakup veering toward the strait in the southeastern portion of the gulf.”</p>



<p>The image was captured by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite on May 30, 2023.</p>



<p><em>Image Credit: NASA Earth Observatory&nbsp;</em></p>



<p><em>—--</em></p>



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Spring ice breakup in the Amundsen Gulf

<p>Human hair, with its varied textures, does more than just crown our heads and serve aesthetic purposes. It might just be the secret that enabled early humans to beat the heat, stay hydrated, and as a surprising consequence, foster the growth of our modern-day brain sizes. According to recent research, the key might lie in our curly locks.</p>



<p>The investigation, led by researchers at <a href="https://www.psu.edu/">Penn State University</a> and Loughborough University, delved into the role of different hair textures in regulating body temperature. The findings suggest that our ancestors' tightly curled hair served a crucial function in the torrid heat of equatorial Africa, where human <a href="https://www.earth.com/news/study-reveals-secrets-of-the-evolution-of-prehistoric-reptiles/">evolution</a> took its course.</p>



<h2 id="h-connection-between-human-heads-and-sunlight">Connection between human heads and sunlight</h2>



<p>Professor Nina Jablonski elaborated on the connection between our scalps and the intense sunlight of our ancestral home. "Humans evolved in equatorial Africa, where the sun is overhead for much of the day, year in and year out," she explained. "We found that tightly curled hair allowed humans to stay cool and actually conserve water."</p>



<p>To understand this unique evolutionary adaptation, the research team used a thermal manikin - a human-shaped model that simulates body heat - to study how different hair textures affect heat gain from solar radiation. The manikin was programmed to maintain an average skin surface temperature of 95 degrees Fahrenheit (35 degrees Celsius) and was set in a climate-controlled wind tunnel.</p>



<h2 id="h-how-the-study-was-conducted">How the study was conducted</h2>



<p>George Havenith, director of the Environmental Ergonomics Research Centre at Loughborough University, described how the experiments were conducted. After establishing base measurements of body heat loss, the researchers simulated solar radiation with lamps and studied how heat loss varied under four different scalp hair conditions - bald, straight-haired, moderately curled, and tightly curled.</p>



<p>By comparing heat loss with and without the lamp exposure, the researchers determined how much solar radiation the scalp absorbed. They also factored in varying wind speeds and simulated sweating to model realistic conditions. The researchers then studied how these hair textures would handle heat and humidity typical of equatorial Africa.</p>



<h2 id="h-what-the-research-team-discovered">What the research team discovered</h2>



<p>The team discovered that all hair types reduced solar radiation to the scalp. However, tightly curled hair stood out as the champion, offering superior sun protection and minimizing the need to sweat for cooling. This research was reported on June 6 in the <a href="http://dx.doi.org/10.1073/pnas.2301760120"><em>Proceedings of the National Academy of Sciences</em></a>.</p>



<p>Tina Lasisi, who conducted this research as part of her doctoral dissertation at Penn State, explains the significance of these findings: "Walking upright is the setup and brain growth is the payoff of scalp hair," she says. As early humans started walking upright, their scalps bore the brunt of the sun’s rays. The brain, a heat-sensitive organ that generates heat, especially when growing larger, needed protection from overheating.</p>



<p>Excessive heat can lead to conditions like heat stroke. Although humans have developed efficient sweat glands to cool down, sweating comes with a cost - water and electrolytes. Lasisi believes that scalp hair evolved as a way to keep humans cool without the body having to expend additional resources.</p>



<h2 id="h-insights-gained-into-human-evolution">Insights gained into human evolution</h2>



<p>She points out that about 2 million years ago, Homo erectus, similar to modern humans in physical build but with a smaller brain size, walked the earth.&nbsp;</p>



<p>"By one million years ago, we’re basically at modern-day brain sizes, give or take. We think scalp hair provided a passive mechanism to reduce the amount of heat gained from solar radiation that our sweat glands couldn’t," says Lasisi.</p>



<p>This interesting research brings us a step closer to understanding the intricate process of human evolution and the multifaceted roles of our physical traits. The use of the thermal manikin, a tool usually used for testing protective clothing, opens new avenues for anthropological research. It helps quantify human data without putting humans in potentially risky situations, as noted by Jablonski.</p>



<h2 id="h-implications-for-life-in-the-21st-century">Implications for life in the 21<sup>st</sup> century</h2>



<p>In addition to unlocking the mysteries of human evolution, the research could have real-world implications for today. Lasisi, who is set to start as an assistant professor of anthropology at the University of Michigan in the fall, compares the protective nature of hair to the role of melanin in our skin.</p>



<p>"The work that's been done on skin color and how melanin protects us from solar radiation can shape some of the decisions that a person makes in terms of the amount of sunscreen needed in certain environments," said Lasisi. "I imagine that similar decision making can occur with hair."</p>



<p>She goes on to reflect on the potential implications for different professions or activities that involve exposure to varied climates. This could include military personnel or athletes who exercise in diverse environments.&nbsp;</p>



<p>"Our findings give you a moment to reflect and think: is this hairstyle going to make me overheat more easily? Is this the way that I should optimally wear my hair?" Lasisi proposed.</p>



<h2 id="h-main-takeaways-from-this-interesting-study">Main takeaways from this interesting study</h2>



<p>In conclusion, the humble curl of our hair is more than just a stylistic feature - it might be a testament to a crucial evolutionary adaptation that helped us grow, thrive, and even develop our present-day brain sizes.&nbsp;</p>



<p>As science continues to uncover these intriguing connections, it becomes increasingly evident that our evolutionary past continues to influence our present and potentially shape our future.</p>



<p>This study represents an interdisciplinary effort involving experts from multiple universities. Key contributors include James Smallcombe from Loughborough University and the University of Australia, Larry Kenney, professor of physiology, kinesiology, and Marie Underhill Noll Chair in Human Performance from Penn State, along with Mark Shriver, professor of anthropology, and Benjamin Zydney, a Penn State alum and former undergraduate research assistant.</p>



<p>The National Science Foundation and the Wenner-Gren Foundation financially supported this research, emphasizing its importance in deepening our understanding of human evolution and potentially influencing our choices and decisions in daily life.</p>



<h2 id="h-more-about-human-hair">More about human hair&nbsp;</h2>



<p>Human hair has a fascinating evolutionary history. It's unique to each person and serves a variety of crucial roles that go beyond aesthetics.</p>



<h3 id="h-physical-protection-for-your-head">Physical protection for your head</h3>



<p>One of the major evolutionary benefits of hair is protection. Hair on our heads shields the scalp from the harmful ultraviolet radiation of the sun. As we saw from the recent research, tightly curled hair does an exceptional job at this, reducing the absorption of solar radiation and helping to keep us cool.</p>



<p>Hair also provides a physical barrier against foreign particles. Eyelashes and eyebrows protect our eyes from dust and other tiny particles, while hair within our nostrils filters out unwanted particles from the air we breathe.</p>



<h2 id="h-sensory-perception">Sensory perception</h2>



<p>Interestingly, body hair also plays a role in sensory perception. Hair follicles are surrounded by a network of nerve endings, making them sensitive to touch. This could have been beneficial in our evolutionary past, allowing us to sense the presence of insects or other potential threats on our skin.</p>



<h3 id="h-communication-and-perceived-attractiveness">Communication and perceived attractiveness</h3>



<p>Moreover, hair plays a significant role in communication and sexual selection. For example, long, lustrous hair is often considered a sign of health and fertility, potentially making it an attractive trait for potential mates. Similarly, certain hairstyles can communicate social or cultural identity.</p>



<h3 id="h-controls-perspiration">Controls perspiration</h3>



<p>Sweat also plays a part in this story. Humans, unlike most mammals, have relatively hairless bodies but are one of the sweatiest creatures on the planet. The evolution of sweating helped our ancestors stay cool while hunting and gathering during the hottest parts of the day. Hair on our heads likely evolved to help wick sweat away from the body, increasing the cooling effect.</p>



<h3 id="h-link-to-geographical-and-ancestral-roots">Link to geographical and ancestral roots&nbsp;</h3>



<p>Furthermore, hair color and texture can be linked to our geographic and ancestral roots. For example, tightly coiled hair, which is common among people of African descent, is believed to have evolved in response to the intense sun and heat of the equatorial region. In contrast, straight hair, often associated with people of East Asian descent, might have evolved to provide warmth and protection from the cold in northern climates.</p>



<p>All in all, human hair is a complex trait that has been shaped by a myriad of evolutionary pressures. It serves multiple functions, from thermoregulation and protection to communication and even attraction. These diverse roles underscore the fact that human hair is much more than a mere accessory; it's a testament to our evolutionary journey and survival story.</p>



<p>—-</p>



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Curly hair kept early humans cool before air conditioning

Human hair, with its varied textures, does more than just...

<p>The stark escalation of human-induced global warming, progressing at a "unprecedented rate," has echoed a pressing alarm, as declared by 50 preeminent scientists. They report that the increase in the global <a href="https://www.earth.com/news/lakes-are-struggling-to-maintain-oxygen-as-temperatures-rise/">temperature</a> is an immediate result of human activities, and it is surging faster than previously anticipated.</p>



<p>Their timely revelation, a "wake-up call," comes at a critical juncture as climate experts convene in Bonn. Their meeting is the prelude to the major COP28 climate conference in UAE, slated for December. The conference will assess global efforts to keep the temperature increase below 1.5°C by 2050.</p>



<p>However, the swift pace of climatic changes makes access to robust scientific evidence crucial for informed decisions. Policymakers, climate negotiators, and civil society groups need this data to effectively respond to the climate crisis.</p>



<p>The UN's Intergovernmental Panel on Climate Change (IPCC) is recognized as a reliable source of scientific information. However, their major assessments typically take five to ten years to complete, creating a critical "information gap" during this rapidly changing climate scenario.</p>



<p>To bridge this gap, scientists from the <a href="https://www.leeds.ac.uk/">University of Leeds</a> have launched a novel open-data, open-science platform — the Indicators of Global Climate Change (IGCC). This online resource, available at <a href="https://igcc.earth/">https://igcc.earth/</a>, will provide annual updates on key climate indicators.</p>



<h2 id="h-critical-decade-for-future-of-our-planet">Critical decade for future of our planet</h2>



<p>Professor Piers Forster, the coordinator of the project and Director of the Priestley Centre for Climate Futures at Leeds, emphasizes the importance of this decade for climate change. He states, "Decisions made now will have an impact on how much temperatures will rise and the degree and severity of impacts we will see as a result."</p>



<p>According to Professor Forster, there is already evidence that greenhouse gas emissions are slowing down, despite current warming rates being at an all-time high. This highlights the need for nimble policy-making, responsive to the latest evidence about the state of the climate system. "Time is no longer on our side. Access to up-to-date information is vitally important," he warns.</p>



<p>The scientists' revelations in the journal <a href="http://dx.doi.org/10.5194/essd-15-2295-2023"><em>Earth System Science Data</em></a> also show how key indicators have evolved since the publication of the IPCC's Sixth Assessment Working Group 1 report in 2021.</p>



<h2 id="h-updated-indicator-findings">Updated indicator findings</h2>



<p>Recent data reveals that human-induced warming, predominantly due to fossil fuel burning, averaged at 1.14°C for the last decade (2013-2022) above pre-industrial levels. This is a rise from 1.07°C between 2010 and 2019. Now, the pace of increase is over 0.2°C per decade.</p>



<p>Additionally, greenhouse gas emissions have reached an all-time high, with human activities releasing approximately 54 (+/-5.3) billion metric tons of carbon dioxide into the atmosphere annually over the last decade (2012-2021).</p>



<p>While there has been a move away from coal burning, it has ironically added to global warming by reducing particulate pollution in the air, which usually has a cooling effect.</p>



<p>Professor Maisa Rojas Corradi, Chile's Minister of the Environment, an IPCC author and scientist involved in this study, emphasizes the importance of regularly updating global change indicators. She says this is critical for maintaining urgency in addressing the climate crisis, allowing for informed decision-making, and fine-tuning national policies.</p>



<h2 id="h-remaining-carbon-budget-has-reached-dire-level">Remaining carbon budget has reached dire level</h2>



<p>A critical insight from the analysis is the rapid decline in the remaining carbon budget, which is the estimate of carbon that can be released into the atmosphere to maintain a 50% chance of keeping the global temperature rise within 1.5°C.</p>



<p>As of 2020, the IPCC calculated the remaining carbon budget to be around 500 gigatonnes of carbon dioxide. By early 2023, this figure had halved to about 250 gigatonnes of carbon dioxide. This precipitous drop is due to the persistent emissions since 2020, compounded by updated estimates of human-induced warming.</p>



<p>Professor Forster warns, "Even though we are not yet at 1.5°C warming, the carbon budget will likely be exhausted in only a few years as we have a triple whammy of heating from very high CO2 emissions, heating from increases in other GHG emissions and heating from reductions in pollution."</p>



<h2 id="h-public-must-be-kept-informed-of-key-indicators">Public must be kept informed of key indicators</h2>



<p>If we aim to keep the 1.5°C goal within our reach and not just a fleeting image in our rearview mirror, we must work relentlessly and urgently to bring down emissions. The Indicators of Global Climate Change project aims to aid this endeavor by ensuring key players have timely and up-to-date data at their disposal.</p>



<p>Dr Valérie Masson-Delmotte, from the Université Paris Saclay, who co-chaired Working Group 1 of the IPCC’s Sixth Assessment report and was involved in the climate indicators project, shared a similar sentiment.&nbsp;</p>



<p>She said, "This robust update shows intensifying heating of our climate driven by human activities. It is a timely wake up call for the 2023 global stocktake of the Paris Agreement - the pace and scale of climate action is not sufficient to limit the escalation of climate-related risks."</p>



<p>It's important to remember that every incremental increase in global warming intensifies climate extremes. This includes heightened frequency and intensity of hot extremes, heavy rainfall, and agricultural droughts.</p>



<p>The Indicators of Global Climate Change (<a href="https://igcc.earth/">https://igcc.earth/</a>) aims to keep this information accessible and up-to-date. The platform will provide annual updates on greenhouse gas emissions, human-induced global warming, and the remaining carbon budget.</p>



<p>Inspired by the financial industry's approach to information presentation, software developers expanded on a successful climate dashboard, the Climate Change Tracker, to build the IGCC website. This interface allows the public to digest complex climate data in a user-friendly format, further enabling informed climate action worldwide.</p>



<h2 id="h-more-about-the-climate-change-tipping-point">More about the climate change “tipping point”&nbsp;</h2>



<p><br>A tipping point in the context of climate change refers to a threshold or a point of no return in the climate system. When this point is crossed, drastic and potentially irreversible changes occur.&nbsp;</p>



<p>This phenomenon is a product of positive feedback loops in the climate system, where a change in one aspect can amplify other aspects, leading to accelerated warming or climatic shifts.</p>



<p>Several key tipping points have been identified by scientists. Here are some of them:</p>



<h3 id="h-melting-of-polar-ice-sheets">Melting of Polar Ice Sheets</h3>



<p>The polar ice sheets in Greenland and Antarctica have a considerable effect on the global climate. Once these ice sheets start to melt, a feedback loop can begin where melting ice reduces the Earth's albedo (reflectivity), which means more sunlight is absorbed, leading to more warming and thus more ice melting. If all of the Greenland ice sheet were to melt, it could lead to a global sea-level rise of about 7 meters.</p>



<h3 id="h-thawing-of-permafrost">Thawing of Permafrost</h3>



<p>Large areas of the Arctic are covered in permafrost - ground that remains frozen throughout the year. This permafrost contains vast amounts of carbon. As the world warms, this permafrost thaws, releasing this carbon as greenhouse gases (carbon dioxide and methane), which in turn accelerates global warming.</p>



<h3 id="h-dieback-of-forests">Dieback of Forests</h3>



<p>The Amazon rainforest, often referred to as the "lungs of the Earth", is another potential tipping point. Deforestation and rising temperatures could cause a significant portion of the forest to die back and transition into savannah, releasing massive amounts of CO2 stored in the forest biomass and reducing the amount of CO2 that the forest can absorb.</p>



<h3 id="h-disruption-of-ocean-currents">Disruption of Ocean Currents</h3>



<p>The Atlantic Meridional Overturning Circulation (AMOC), a major ocean current system, plays a key role in regulating the global climate. Increased freshwater from melting ice can disrupt this system, leading to potentially severe consequences for weather patterns, particularly in Europe and North America.</p>



<p>Crossing any of these tipping points could lead to severe and rapid changes in the global climate system. Many scientists believe that we are already close to or have crossed some of these tipping points, but there is ongoing debate over precisely when and how these thresholds will be breached.&nbsp;</p>



<p>Understanding and predicting these points is a major focus of climate research and adds urgency to the need for significant reductions in greenhouse gas emissions.</p>



<p>—-</p>



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Greenhouse gas emissions reach another all-time high

The stark escalation of human-induced global warming, progressing at a...

Closeup,Of,Bluebell,Flowers,Seen,Around,An,Unmarked,Grave,Stone.

<p>Scientists have made an incredible <a href="https://www.nationalgeographic.com/science/article/earliest-human-burial-homo-naledi-berger">discovery</a> that may challenge our understanding of human evolution - the world's oldest known burial site.&nbsp;</p>



<p>The find is located within a cave system in South Africa and is linked to an archaic species of human, Homo naledi. Remarkably, this extinct species was capable of not just burying their dead but also etching and painting symbols onto their graves.</p>



<p>Such behavior might sound familiar, as it's typical of us, Homo sapiens. However, the Homo naledi <a href="https://www.earth.com/news/differences-in-the-mammalian-and-reptilian-brain-revealed/">brain</a> is only the size of an orange - a dimension that previously led scientists to believe it was incapable of creating symbolic or "meaning-making" activities.</p>



<h2 id="h-findings-predate-homo-sapiens-burial-rituals-by-100-000-years">Findings predate Homo sapiens burial rituals by 100,000 years</h2>



<p>This discovery has potentially historic implications. Until now, the assumption has been that these sophisticated behaviors were unique to larger-brained ancient Homo sapiens. However, the recent findings predate our species by at least 100,000 years, suggesting a fundamental rewrite of our historical understanding.</p>



<p>Lee Berger, a leading paleoanthropologist collaborating with <a href="https://www.nationalgeographic.com/">National Geographic</a>, was at the helm of this breakthrough. He found the burial site 100 feet deep within the UNESCO world heritage site known as the Cradle of Humankind, near Johannesburg.</p>



<p>This is not the first time Homo naledi has made headlines. The first remnants of this species within the South African cave system were unearthed in 2013. The expedition revealed a trove of skeletal remains of adults and children under the earth, including a single body with 83 identifiable bone fragments and teeth.</p>



<h2 id="h-homo-naledi-remains-mostly-a-mystery">Homo naledi remains mostly a mystery</h2>



<p>Homo naledi is a primitive species positioned between apes and modern humans. This ancient relative has a brain size comparable to that of a chimpanzee and stands about five feet tall. Their curved fingers and toes, adept hands for wielding tools, and feet designed for walking, have already challenged the idea that human evolution followed a straight path.</p>



<p>Symbols marking the graves were identified by Berger and his team in July 2022 and have since been published. These deeply impressed cross-hatchings and other geometric shapes were found on surfaces that appeared to have been intentionally prepared and smoothed. Interestingly, they appeared thought out and were consistently repeated using some sharp tool. Even though some markings appear to have been made by mistake or left unfinished, a total of 46 non-natural engraved marks were discovered near one of the graves.</p>



<p>These findings draw parallels with our ancient Neanderthal relatives, who used similar symbols nearly 600,000 years ago, and Homo sapiens in South Africa about 80,000 years ago. According to Berger, the implications of the markings, along with evidence of intentional burials, suggest that Homo naledi engaged in meaningful activities associated with death.</p>



<p>Berger shared his observations with AFP, stating, "It seems an inevitable conclusion that in combination, they indicate that this small-brained species of ancient human relatives were performing complex practices related to death. That would mean not only are humans not unique in the development of symbolic practices, but may not have even invented such behaviors."</p>



<h2 id="h-researchers-made-other-fascinating-discoveries-at-the-site">Researchers made other fascinating discoveries at the site</h2>



<p>Further intriguing artifacts included engravings forming geometrical shapes on a cave pillar's purposefully smoothed surfaces. At the center of the latest studies were oval-shaped interments uncovered during 2018 excavations in the underground cave system. These holes, thought to have been deliberately dug, were filled to cover the bodies and contained at least five individuals.</p>



<p>"These discoveries show that mortuary practices were not limited to H. sapiens or other hominins with large brain sizes," noted the researchers.</p>



<p>However, these findings may ruffle feathers within the paleontological community, where Berger has faced criticism in the past for jumping to conclusions and lacking scientific rigor. When he first suggested in 2015 that Homo naledi was capable of behavior beyond what its small brain size would suggest, many within the scientific community met his assertions with skepticism.</p>



<p>"That was too much for scientists to take at that time. We think it's all tied up with this big brain. We're about to tell the world that's not true," said Berger.</p>



<h2 id="h-more-analysis-and-research-is-required">More analysis and research is required</h2>



<p>While these latest discoveries still require additional analysis, the researchers involved believe they have made strides in our understanding of human evolution.</p>



<p>"Burial, meaning-making, even 'art' could have a much more complicated, dynamic, non-human history than we previously thought," said study co-author Professor Agustin Fuentes of Princeton University.</p>



<p>Carol Ward, an anthropologist from the University of Missouri who wasn't involved in the research, told AFP: "These findings, if confirmed, would be of considerable potential importance. I look forward to learning how the disposition of remains precludes other possible explanations than intentional burial and to seeing the results once they have been vetted by peer review."</p>



<p>Undoubtedly, the Homo naledi discoveries represent a fascinating chapter in our understanding of early human behaviors and the evolution of our species. While the narrative may need to be revised and there is still much to learn, the findings remind us that our evolution has been anything but a straight line.</p>



<h2 id="h-more-about-homo-naledi">More about Homo naledi</h2>



<p>Homo naledi is an extinct species of the genus Homo, which also includes modern humans, Homo sapiens. The species was announced to the world in 2015 after the discovery of its remains in the Rising Star cave system in South Africa in 2013.</p>



<p>One of the remarkable features of the Homo naledi discovery was the sheer number of fossils found. Over 1,500 individual pieces representing more than 15 individuals, from infants to elderly adults, were recovered in the initial excavation, making it one of the richest fossil sites in Africa.&nbsp;</p>



<p>The cave system is extremely difficult to access, which has led to the hypothesis that Homo naledi may have intentionally disposed of its dead - a behavior previously thought to be unique to Homo sapiens.</p>



<h3 id="h-human-like-in-many-ways">Human-like in many ways</h3>



<p>Homo naledi was small-brained but humanlike in many ways. The species' brain size is estimated to have been about 465 to 560 cubic centimeters, which is roughly one-third the size of the modern human brain. Despite this, their physical characteristics showed a fascinating mix of primitive and modern traits. They stood about five feet tall and had a slender body mass, similar to small-bodied human populations.</p>



<p>Homo naledi's feet were virtually indistinguishable from those of modern humans, suggesting that they were capable of long-distance walking and possibly running. Their hands had curved fingers, suggesting climbing abilities, but also featured a humanlike wrist and thumb, which indicates they may have been capable of making and using tools, although no tools have been found associated with the fossils.</p>



<p>The species also had relatively small teeth, more similar to those of modern humans than to earlier hominins, and features of the skull, particularly in the jaw, that are more similar to those of Homo genus than to australopithecines.</p>



<h3 id="h-fossils-discovered-were-not-as-old-as-initially-believed">Fossils discovered were not as old as initially believed&nbsp;</h3>



<p>The age of the Homo naledi fossils has been difficult to determine. Initially, because of the mix of primitive and modern traits, it was speculated that they might date from a very early period in the evolution of the Homo genus.&nbsp;</p>



<p>However, in 2017, the fossils were dated to between 335,000 and 236,000 years ago, which means that Homo naledi was contemporary with the earliest Homo sapiens. The relatively recent age of these fossils makes the mix of primitive and modern traits exhibited by Homo naledi even more intriguing.</p>



<p>The discovery of Homo naledi had added a rich new chapter to our understanding of hominin evolution, suggesting that the journey to modern humans was not a straight line but a tree with many branches.&nbsp;</p>



<p>Their small brains, yet humanlike behaviors (like potentially burying their dead), challenge traditional views of cognitive evolution. Further study and discovery of other fossil evidence will continue to refine our understanding of this fascinating species.</p>



<h2 id="h-more-about-early-human-ancestors">More about early human ancestors</h2>



<p>The evolution of humans has been a complex journey, and there are several known species of early human ancestors, known as hominins, that have played crucial roles in our lineage. Here are some of the more notable ones:</p>



<h3 id="h-australopithecus-afarensis-lucy">Australopithecus afarensis (Lucy)</h3>



<p>This species lived between about 3.9 and 2.9 million years ago and is one of the older known species in our lineage. The most famous fossil of this species is "Lucy," a partial skeleton found in Ethiopia. Australopithecus afarensis was bipedal and walked upright, but also had adaptations for tree climbing.</p>



<h3 id="h-homo-habilis">Homo habilis</h3>



<p>Living between 2.1 and 1.5 million years ago, Homo habilis is known as the "handy man" because this species was associated with the creation of stone tools. Homo habilis had a larger brain than the Australopithecines and showed more humanlike characteristics.</p>



<h3 id="h-homo-erectus">Homo erectus</h3>



<p>This species emerged around 2 million years ago and lived until about 100,000 years ago. Homo erectus is the first known human ancestor to have body proportions similar to those of modern humans and is believed to have been the first hominin to have left Africa, with remains found in various parts of Asia and Europe.</p>



<h3 id="h-neanderthals-homo-neanderthalensis">Neanderthals (Homo neanderthalensis)</h3>



<p>Neanderthals lived in Europe and western Asia from about 400,000 until about 40,000 years ago. They were close relatives of modern humans and had a brain size comparable to ours. Neanderthals used sophisticated tools, wore clothing, controlled fire, and may have had language.</p>



<h3 id="h-denisovans">Denisovans&nbsp;</h3>



<p>Like Neanderthals, Denisovans are a relatively recent discovery, known mostly from DNA found in a single finger bone discovered in a Siberian cave. They lived at the same time as early Homo sapiens and Neanderthals, and genetic evidence suggests they interbred with both.</p>



<h3 id="h-homo-naledi">Homo naledi</h3>



<p>As mentioned earlier, Homo naledi is a relatively recent addition to the human family tree, with a mix of primitive and modern features. The species, found in South Africa, is believed to have lived several hundred thousand years ago.</p>



<h3 id="h-homo-floresiensis-the-hobbit">Homo floresiensis (The Hobbit)</h3>



<p>This species was discovered in 2003 on the Indonesian island of Flores. The adults stood only about 3.5 feet tall, which led to the nickname "the Hobbit." They lived from about 100,000 to 50,000 years ago.</p>



<p>These are just a few of the many hominin species that have been discovered. Each new discovery, like Homo naledi, adds to the complex picture of human evolution, demonstrating that our evolutionary history is more of a branching tree with many dead ends, rather than a straightforward path leading directly to Homo sapiens.</p>



<p>—-</p>



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