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The Joshua tree (Yucca brevifolia) is a remarkable evergreen, treelike plant found only in the southwestern United States. It was named by Mormon settlers in the early 1800s. Upon seeing the limbs of this plant branching upwards to heaven, the…

Collectively, members of the class Amphibia are facing massive reductions in total numbers, and the overall biodiversity of amphibians across the globe is under threat. Scientists have determined that global climate change and habitat destruction…

Sea-level rise is caused by adding mass (water) and heat to the ocean. The Antarctic ice sheet represents a potentially large source of water. Knowing the speed and direction (velocity) at which the Antarctic ice sheet is flowing to the ocean is…

Charles Robert Darwin (February 12, 1809 – April 19, 1882) is one of the most celebrated and eminent scientists of the past few centuries, with his broadest and most notable influence arising from his theory of evolution by means of natural…

It has been a long-held belief that, as a result of hunting habits, early humans were partly or even primarily responsible for the decline and eventual extinction of most of the largest mammalian species that inhabited ancient Africa. These large…

Researchers from Rice University in Houston, Texas, United States, have found that climate change could potentially increase the size of stalled high-pressure weather systems (ridges) known as “blocking events,” according to global climate modelling…

The critically endangered northern white rhinoceros (Ceratotherium simum cottoni) is a subspecies of white rhino that is on the brink of complete extinction, with only two individuals left in captivity and no known members reported in the wild. The…

Trees provide substantial benefits to the environment. In addition to improving air quality, reducing stormwater runoff, serving as a wildlife habitat, and sequestering carbon by absorbing carbon dioxide, trees also cool the atmosphere through shade…

The International Union for Conservation of Nature (IUCN)—the global authority on the status of the natural world—estimates that approximately 5–10% of the world's insect species (class Insecta, phylum Arthropoda) are threatened and facing…

Sand is mined for many applications, but the largest use by far is for fine aggregate in concrete. Smaller quantities of sand are used for fracking, water treatment (filtration), metal casting, and making glass, silicon chips, and ceramics. Concrete…

At the Woranso-Mille paleontological site in northern Ethiopia, researchers have discovered a 3.8 million-year-old cranium (skull) belonging to a primitive hominin known as Australopithecus anamensis. Initially unearthed in 2016, but not reported…

A study published in the journal Atmospheric Environment (April 2019), comparing the differences in air pollution caused by automobiles powered by internal combustion (conventional) engines versus electric vehicles (EVs) powered by batteries,…

Researchers have reached a key new milestone in the continuing search for worlds like Earth that could support life elsewhere in the universe. For the first time, water vapor has been detected in the atmosphere of an exoplanet that resides within…

Researchers surveying ice loss from 650 glaciers across a 2000-kilometer (1240-mile) west-to-east expanse of the Himalayan Mountains reported in the journal Science Advances (June 2019) significant melting caused by global climate change over the…

All freshwater comes from precipitation over land, which is distributed on Earth as blue and green water. Blue water—that is, surface and groundwater—is stored as freshwater in lakes, streams, ice, and snow, as well as below ground. Green water is…

Researchers Chi Ma of Caltech and Alan Rubin of the University of California at Los Angeles reported in the journal American Mineralogist (September 2019) the discovery in a meteorite of the first natural occurrence of the iron-carbide mineral…

Earth’s surface temperature is warming, and the Arctic region is warming even faster. Yet winters in the mid-latitudes of Asia, Europe, and the United States have been colder than average, thanks to blasts of record-breaking frigid air caused by…

After reports that June 2019 was the warmest June on record, July 2019 followed with the dubious distinction that it was the warmest month since atmospheric temperature record-keeping began in 1880, according to the U.S. National Oceanic and…

Researchers at Duke University in North Carolina (United States) have developed a test for distinguishing lead isotopes found in coal fly ash from lead isotopes found in other lead-containing sources, such as paint. Fly ash is a fine particulate…

A report by a team of conservation biologists concludes that the total number of birds in North America has dropped precipitously since 1970. Annual surveys monitoring the biodiversity and abundance of bird populations across the North American…

The golden jackal (Canis aureus) is the most widely distributed jackal in the world, populating widely diverse habitats across extensive ranges. In particular, this canine predator occupies large areas of northern and eastern Africa, the Middle…

Reusable sponge-like (foam) sorbent materials for cleaning up oil spills may soon become available, as a result of promising research from multiple groups. Oil spills damage ecosystems and habitats, harm and kill wildlife and plants, contaminate…

In 1987, the Montreal Protocol, the international treaty banning chemicals that deplete the ozone layer, was adopted. Thirty years later, NASA scientists reported in the journal Geophysical Research Letters (January 2018) satellite measurements…

The Asian longhorned tick (Haemaphysalis longicornis), also known as the bush tick, is a troublesome parasitic species and is an important vector of disease agents. (Note that vectors are capable of biologically transferring a pathogen from one…

On August 5, 2018 at 6:46 p.m. local time, a magnitude 6.9 earthquake struck in Pulau Lombok, Indonesia. The earthquake occurred as the result of thrust faulting at a depth of 10.5 km (6.5 mi) in northern Lombok, according to the United States…

Colony collapse disorder (CCD) is a baffling detrimental condition in colonies of honeybees (Apis mellifera). It is characterized by a rapid loss of the adult bee population, with an absence of dead bees in and around affected colonies. No single…

Crown-of-thorns starfish or sea stars (Acanthaster planci; order Valvatida) are predatory marine invertebrates that feed on phytoplankton found on coral. They are native inhabitants of coral reefs in both the Indian Ocean and Pacific Ocean and are…

Conservationists have determined that the Bornean orangutan (Pongo pygmaeus) is disappearing much more rapidly than previously thought. Since 1999, the total number of Bornean orangutans declined by at least 148,000 individuals. The chief culprits…

The Mississippi River has undergone extensive river engineering for flood control, with its 3500-mile Mississippi River and Tributaries levee (artificial-embankment) system. However, researchers reported in Nature (April 2018) that disconnecting the…

The warming temperatures attributed to global climate change are making it more difficult for sea turtle populations to survive. As a result of the unusual developmental processes found in many reptiles, including some species of turtles, the sex of…

Sunscreens are polluting the ocean, and increasing evidence points toward some ultraviolet-light–absorbing chemicals found in sunscreens as being harmful to marine life—particularly corals at popular tourist destinations. While working toward…

The evolutionary transition of certain dinosaurs into modern birds has long been an active area of paleontological research. Because the members of the class Aves are living representatives of theropod dinosaurs, paleontologists have sought fossil…

In the fall of 2014 and early winter of 2015, an estimated 250,000 to 500,000 seabirds known as Cassin's auklets (Ptychoramphus aleuticus) died along the Pacific Coast from California to British Columbia, Canada. Researchers have now reported the…

Neonicotinoids (also termed neonics) comprise a class of insecticides and pesticides that chemically resemble nicotine. They are the most widely used insecticides in the world and are deployed by plant and crop farmers because these chemical…

Mammals possess a certain gene, termed PON1, which encodes a protein enzyme (paraoxonase) that is used to process the cholesterol lipids and fatty acids found in food. This gene evolved millions of years ago and is functionally active in terrestrial…

The Northern white rhinoceros (Ceratotherium simum cottoni)—one of two white rhino subspecies—is functionally extinct. Officially, this subspecies is classified by the International Union for Conservation of Nature and Natural Resources (IUCN) as…

Humans' contributions to global warming through burning fossil fuels and other actions (for example, detrimental land-use practices) have resulted in sharp increases in the levels of atmospheric carbon dioxide (CO2). These rising levels of CO2 also…

A newly identified reptilian fossil has pushed back the phylogenetic (evolutionary) family tree of Squamata [the dominant order of living reptiles, comprising lizards, snakes, and amphisbaenians (mostly limbless lizards that resemble worms)] by 75…

Scientists have long thought that dinosaur eggs were white in color and that the evolution of colored eggs in birds was strictly an avian innovation that occurred after the demise of the nonavian dinosaurs. However, technical advancements in the…

Limiting the effects of climate change to the greatest extent possible will require reducing greenhouse-gas (GHG) emissions and removing GHGs from the atmosphere. In addition, the shared goal of the countries that have entered into the Paris Climate…

One notable study of predator-prey relationships, specifically between wolves and moose, has been conducted on Isle Royale since the late 1950s. Isle Royale is the largest island in Lake Superior. It was established as a national park in the United…

Quorum sensing is a process by which bacteria monitor their own population density by detecting the levels of signal molecules that are released by the bacteria. It is a unique phenomenon of cell-to-cell communication, enabling microorganisms to…

The Iberian lynx (Lynx pardinus; also known as the Spanish lynx), which inhabits the shrublands of southwestern Spain and Portugal, was on the verge of extinction at the beginning of the twenty-first century. At that time, this wild cat species was…

By July 6, 2018, beaches on the eastern coast of St. Vincent—an island located in the southeastern Caribbean Sea (Lesser Antilles)—were covered nearly one-meter deep with rotting brown algae (seaweed), known as Sargassum, posing multiple problems…

Destructive blooms of Karenia brevis, a dinoflagellate species of algae that imparts a red color to ocean waters when the microorganisms grow and accumulate to unusually high quantities, are causing unprecedented environmental and ecosystem damage…

Trophic ecology is the general study of the structure of feeding relationships among organisms in an ecosystem. These feeding or trophic relationships are often represented as food webs or food chains. One very important phenomenon of trophic…

For more than 10 years, natural-gas-fired power plants have been touted as “cleaner” electrical power generators, producing half the carbon dioxide (CO2), one-third of the nitrogen oxides (NOX), and negligible sulfur oxides (SOX) compared to…

Biocontrol, or biological control, is the natural or applied regulation of populations of pest organisms—especially insects—through the role or use of natural enemies. In other words, biocontrol uses living organisms to reduce and eliminate pest…

As the global climate becomes hotter and drier, heat mitigation in urban areas through the use of cool roofs is becoming increasingly important. Cool roofs reflect more sunlight and absorb less heat than conventional roofs, according to the U.S.…

There are 27 ways a heat wave can kill you, according to a report in the American Heart Association journal Circulation: Cardiovascular Quality and Outcomes (November 2017). By 2100, at the current rate of greenhouse-gas emissions, three-quarters of…