Reference Terms
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Topographic map
Topographic maps, also called contour maps, topo maps or topo quads, are maps that show topography, or land contours, by means of contour lines. Contour lines are curves that connect contiguous points of the same altitude (isohypse). In other words, every point on the marked line of 100 m elevation is 100 m above mean sea level.
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Earth & Climate News
May 2, 2026
May 2, 2026 Crabs’ famous sideways walk may trace back to a single evolutionary moment 200 million years ago. Researchers found that most modern crabs inherited this trait from one ancestor—and never looked back. The movement likely gave them an edge, ...
May 2, 2026 Two of the most dangerous fault systems on the U.S. West Coast may be more connected than scientists once thought. New research suggests the Cascadia subduction zone and the San Andreas fault can “sync up,” triggering earthquakes within minutes ...
May 1, 2026 Scientists have uncovered a tiny wall-dwelling spider named Pikelinia floydmuraria, inspired by Pink Floyd. Despite its size, it’s a fierce predator that hunts ants much larger than itself and helps reduce common urban pests like mosquitoes and ...
Apr. 30, 2026 Australia’s famous Twelve Apostles didn’t just erode into existence—they were slowly pushed up from the ocean floor by powerful tectonic forces over millions of years, new research reveals. Scientists discovered that these towering limestone ...
Apr. 30, 2026 Deep beneath the Southern Ocean, a quiet but alarming shift is underway: warm water is creeping closer to Antarctica, and scientists are now seeing it clearly for the first time. By combining decades of ship data with robotic float measurements and ...
Apr. 29, 2026 For the first time, scientists have watched a subduction zone literally fall apart beneath the ocean floor. Using advanced seismic imaging, they found the Juan de Fuca plate splitting into fragments as it sinks beneath North America. Rather than ...
Apr. 28, 2026 A new study suggests Neanderthals didn’t go extinct simply because of climate change or competition with Homo sapiens. Instead, the key difference may have been social connectivity—Homo sapiens formed stronger, more flexible networks that helped ...
Apr. 27, 2026 The mysterious collapse of the Maya civilization may not have been driven solely by drought after all. New evidence from lake sediments in Guatemala reveals that one key city, Itzan, enjoyed a stable climate even as its population abruptly vanished. ...
Apr. 27, 2026 A mysterious “golden orb” found more than two miles deep in the Gulf of Alaska left scientists baffled for over two years, sparking wild speculation about its origins. After an intensive ...
Apr. 27, 2026 A major new study finds that living in pesticide-heavy environments could raise cancer risk by up to 150%, even when the chemicals are considered “safe” on their own. The research suggests these mixtures may silently damage cells years before ...
Apr. 26, 2026 For decades, the Gulf of Panama has relied on strong seasonal winds to trigger upwelling, bringing cool, nutrient-packed water to the surface. But in 2025, this dependable event didn’t happen. Researchers point to unusually weak winds as the ...
Apr. 25, 2026 As Alaska’s rivers warm, invasive northern pike are becoming noticeably more voracious. Scientists discovered that pike of all ages are eating more fish, with young pike increasing consumption by over 60%. Warmer water speeds up their metabolism, ...
Latest Headlines
updated 12:56 pm ET
May 2, 2026 A centuries-old vision of a mechanical volcano has finally erupted into reality, as two University of Melbourne engineering students recreated a design first imagined in 1775 by volcanology ...
Apr. 29, 2026 New experiments suggest that freezing and thawing on early Earth may have helped primitive cell-like structures grow and evolve. Tiny lipid bubbles behaved very differently depending on their ...
Apr. 26, 2026 Scientists have uncovered a surprising new picture of human origins that challenges the long-held idea of a single ancestral population in Africa. By analyzing genetic data from diverse modern ...
Apr. 25, 2026 For ages, wall lizards coexisted in three distinct color types, each with its own strategy for survival. Now, a powerful green variant is taking over. These dominant “Hulk” lizards are ...
Apr. 25, 2026 Beneath East Africa’s Turkana Rift, scientists have found the crust is thinning to a critical point, suggesting the continent is gradually breaking ...
Apr. 24, 2026 The golden oyster mushroom may be a culinary hit, but it’s becoming an ecological problem. Scientists warn it’s spreading quickly through U.S. forests, where it outcompetes native fungi and ...
Apr. 24, 2026 Microplastics are floating through the atmosphere and spreading across the globe, but their true origins have been misunderstood. New research shows land sources emit over 20 times more microplastic ...
Apr. 24, 2026 Ancient Antarctic ice is revealing a surprising new chapter in Earth’s climate story, stretching back 3 million years. By analyzing tiny pockets of trapped air and rare gases, scientists have ...
Apr. 24, 2026 Beneath the dry farmland of New South Wales lies a hidden window into a lost rainforest teeming with life from 11-16 million years ago. At McGraths Flat, scientists have uncovered fossils preserved ...
Apr. 23, 2026 Scientists have mapped how Earth’s deepest mantle is being deformed—and the results point to long-lost tectonic plates buried thousands of ...