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Bats are members of the order Chiroptera, which is the second-largest order of living mammals. The geographic distribution of these flying mammals is tremendous as well, ranging from the limit of trees in the Northern Hemisphere to the southern tips…

The Hudson River estuary in the United States experiences a tide from New York Harbor (river kilometer 0/river mile 0) to Troy, New York (river kilometer 244/river mile 152). In the lower 60 kilometers (37 miles) of the Hudson River, the water is…

A clade of ancient birds known as lithornithids (chicken-sized, long-beaked birds), who lived approximately 40–70 million years ago, possessed a unique vibrotactile bill-tip organ that allowed these birds to detect vibrations in the ground. The…

Wildfires are a natural phenomenon in many ecosystems, including forests along the U.S. Pacific West Coast, as natural fires serve to rejuvenate ecological communities. However, from mid-August through mid-September 2020, forests in California,…

There is a growing body of evidence that many of the thousands of prescription and over-the-counter medications ultimately make their way into water bodies and drinking-water supplies. Typical wastewater treatment plants may not be effective at…

Microplastics are raining down on national parks and other protected areas in the western United States at the rate of about 132 pieces of microplastic per square meter every day, according to a report in the journal Science (June 2020).…

Wildfires, also termed bushfires or forest fires, are currently devastating large swaths of land in Australia. Detrimental ecologic consequences of these uncontrolled combustions of forest fuels and vegetation are numerous. One of the most serious…

The American beech (Fagus grandifolia) is native to forest regions east of the Mississippi River and is a key tree species in the United States. In particular, it is very abundant from Ohio to the New England states. The tree is also found in the…

Many questions concerning the sustainable production of biofuels have emerged over recent years in terms of land and water use, pollution from fertilizer and pest-control chemicals, greenhouse-gas production, net energy production, and whether…

Obscured by a hazy atmosphere 100 times thicker than Earth's, Venus is a notoriously difficult world to study. Ground temperatures on Venus exceed 450°C (842°F)—enough to melt lead and to have quickly degraded the Soviet robotic landers last placed…

The novel coronavirus SARS-CoV-2 that emerged in central China in late 2019 and subsequently spread across the world in 2020 led to the COVID-19 pandemic. The emergence of a previously unknown pathogen—such as the novel coronavirus—that could affect…

The world’s oceans and coasts provide a natural sink for excess carbon in the atmosphere. Scientists refer to carbon that is captured and stored this way as blue carbon. Well-known blue-carbon examples include mangroves and salt marshes—wetland…

Using an artificial intelligence technique known as deep learning and high-resolution remote sensing, scientists have counted and mapped the location of trees in 11,000 satellite images covering more than 1.3 million square kilometers (500,000…

During the past decade, the automotive industry has converted more than 50 percent of its internal combustion engines from a traditional technology called port fuel injection (PFI) to a new technology called gasoline direct injection (GDI). The…

Mucus produced by the common garden snail (Helix aspersa) is green. The slime is not actually green in color but is “green” in terms of its environmentally friendly chemistry. It turns out that this snail’s mucus has chemical properties as a…

Life on Earth has been punctuated by a number of catastrophic mass extinctions throughout history. During these events, diverse taxonomic groups collapsed from the relatively rapid and widespread extinction of large numbers of species. Precipitated…

Conservationists are alarmed by significant reductions in insect populations worldwide. Based on recent biodiversity surveys and entomological studies, scientists estimate that more than 40% of the world's insect species (class Insecta, phylum…

Of the three extant elephant species, two inhabit Africa: the African bush or savanna elephant, Loxodonta africana; and the smaller African forest elephant, L. cyclotis. The African bush elephant is the largest living land mammal and is primarily…

All of the many diverse breeds of dogs, including both domestic and wild dogs (wolves, coyotes, foxes, jackals, and dingoes), belong to the genus Canis in the mammalian family Canidae. One intriguing example of an obscure wild dog is the New Guinea…

Ground-level, or tropospheric ozone (O3), is a strong oxidizing agent that reacts with living tissue. Consequently, tropospheric ozone is considered an air pollutant and a respiratory irritant at low concentrations. At higher concentrations,…

Scientists have identified the earliest known fossil of a modern bird. The fossil remains—comprising an almost-complete skull and a few limb bones embedded in rock—were discovered in a limestone quarry in Belgium. Estimated to be approximately 66.7…

A rare and very large area of severely depleted ozone (03) opened up in the stratosphere above the Arctic Circle in March 2020. Scientists attribute this ozone hole to the persistence of a very strong polar vortex (a jet stream that circles the…

Concrete is the most widely used construction material worldwide because of its versatility, strength, and durability. Applications range from roadways and dams to furniture and tiles. With proper manufacturing, reinforcement, and engineering…

The Tasmanian devil (Sarcophilus harrisii) is the world's largest living marsupial carnivore. For tens of thousands of years, this fierce animal could be found throughout the continent of Australia, as well as inhabiting the island of Tasmania.…

Members of the order Pristiophoriformes within the vertebrate subphylum comprise an unusual group of sharks. Collectively known as sawsharks, these marine fishes are distinguishable from other elasmobranchs (sharks, skates, and rays) by a number of…

Many trees in forests worldwide rely on natural fires to create growing conditions necessary to perpetuate the ecosystem, or to stimulate germination. However, for more than 100 years, humans have been suppressing frequent natural low-intensity…

Persistent changes in the Earth's climate that have been occurring primarily as a result of human-caused greenhouse-gas emissions since the mid-twentieth century have led to significant increases in infectious diseases in wildlife, both in terms of…

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…

Eastern equine encephalitis is a rare infectious viral disease that primarily affects humans and equines (horses, mules, donkeys, and zebras). It is caused by a mosquito-borne virus (arbovirus) that is native to the eastern half of the United…

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…

Photosynthesis is a key natural process utilized by plants and is necessary for proper plant growth. Specifically, photosynthesis uses light to manufacture chemical compounds, including organic compounds—primarily carbohydrates—that are derived from…

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…

The Komodo dragon (Varanus komodoensis), a type of monitor lizard belonging to the reptilian order Squamata, is a tremendously powerful carnivorous predator. The creature is indigenous to a small number of Indonesian islands, including Komodo, 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…

Marburg hemorrhagic fever (also referred to as Marburg virus disease) is a rare, exotic viral disease that affects both humans and nonhuman primates. The reservoir hosts of Marburg virus are African (or Egyptian) fruit bats (Rousettus aegyptiacus),…

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…

Pesticides—including insecticides and herbicides—are chemical products used to control, reduce, or eliminate organisms that are harmful to cultivated plants. However, the use of pesticides on plants that provide foods for human consumption is often…

The killer whale, or orca, is a predatory cetacean typically found in cold ocean waters. With its easily recognizable black body and distinct white patches over the eyes and around the belly, the orca is a top (apex) predator in the marine…

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…

More apples are consumed worldwide than any other temperate-zone tree fruit. Apples are eaten fresh, processed into jellies and preserves, cooked in pies and pastries, and made into sauces. Therefore, the cultivation of the trees (genus Malus) that…

Cannabidiol (CBD) is the predominant cannabinoid (chemical constituent) of the more than 100 cannabinoids found in the hemp variety of the plant Cannabis sativa. There are preliminary, yet unproven, claims that CBD may offer benefits for treating…

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…

Neonicotinoid insecticides are the most used insecticide worldwide and have been linked to the decline of pollinator insects. In 2018, the European Union banned the outdoor use of three neonicotinoid insecticides: clothianidin, imidacloprid, and…

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 prevalence of diseases caused by ticks, mosquitoes, and fleas that feed on the blood of humans has increased dramatically. Over a 13-year span (the years 2004 through 2016), the incidence of tick-, mosquito-, and flea-borne diseases in humans…

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…

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…

To better understand the nutritional effects (health benefits), chemical composition, growing conditions, and shelf life of microgreens, a team of researchers reviewed the science behind them in the Journal of Agricultural and Food Chemistry…

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…

It is estimated that 1 gram of soil can be inhabited by up to 109 microorganisms and approximately 60,000 bacterial species. Moreover, soil harbors a vast reservoir of antimicrobial agents, and soil-dwelling bacteria have played a key role in the…

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…

The biotechnology used in the creation of genetically modified crops is being expanded to encompass the bioengineering of plants that contain therapeutically important proteins and molecules that can be utilized in the manufacturing of…

Roman marine concrete, having lasted for nearly 2000 years, is a highly durable material. In contrast, modern marine concrete, which is made using Portland cement, may start to degrade in as few as 50 years. Researchers have now discovered why. As…

Recent excavations in Asia unearthed a pristine, three-dimensional fossil of a tiny dinosaur tail with preserved feathers and soft tissues (presumably skin). In 2016, investigators in northern Myanmar (Burma) recovered a piece of Cretaceous-era…

In 2016, animal researchers and geneticists concluded that the giraffe (genus Giraffa), once thought to consist of a single extant species (Giraffa camelopardalis), comprises four distinct species: the northern giraffe (Giraffa camelopardalis),…

Bananas (Musa genus) are one of the world's most valuable and popular primary agricultural commodities. However, the most prevalent naturally occurring bananas, that is, those of the Cavendish variety, are being severely decimated by Panama disease…

Global climate change affects all areas of the Earth, with some regions experiencing greater impacts than others. In particular, the Arctic treeline—that is, the southern limit of the Arctic Bioclimate Zone—is being affected to various degrees by…

Survival prospects for the honeybee (Apis mellifera) look increasingly promising as entomologists and beekeepers have reported a dramatic increase in the population numbers of these essential insects in North America and Europe. Honeybees, which are…

Hurricane Harvey made landfall near the middle of the Texas Gulf Coast on August 25, 2017 as a Category 4 storm on the Saffir-Simpson Hurricane Wind Scale and essentially hovered over the region for seven days, unleashing heavy rain and causing…

On August 30, 2017, just as Hurricane Harvey was winding down in Texas, tropical storm Irma formed near the Cape Verde Islands located off the northwest coast of Africa and began moving west-northwest. According to the U.S. National Hurricane…

If three occurrences constitute a trend, then catastrophic storms—that is, Category 4 or 5 storms on the Saffir-Simpson Hurricane Wind Scale—are the trend for Atlantic hurricanes in 2017. One day after forming as a tropical depression, Potential…

Forests absorb and store carbon. If this ability is hampered, then levels of atmospheric carbon will increase and global temperatures will rise, leading to potentially drastic climatic changes. In particular, deforestation (the permanent elimination…

Through study of the fossil record, paleontologists can frequently identify when an ancient species or taxon (a grouping of related organisms) first emerged in evolutionary history. (Paleontologists often prefer the term taxon over species because…

Ever since the Lusi mud volcano began erupting on May 29, 2006, in the Porong subdistrict of Sidoarjo in East Java, Indonesia, scientists have been unable to agree on its cause. Two days before to the eruption, two events occurred—a magnitude 6.3…