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As social animals, humans tend to form groups that can range in size from a few individual members to entire nation-states. Historically and through the present day, human groups frequently come into conflict. A noted feature of human intergroup…

Humans have used dried bovine dung (manure) as a fuel source since prehistoric times. In India, for example, many people burn cow or buffalo dung for cooking fuel. This bioresource provides a low-cost fuel as well as an efficient means of waste…

Wind-pollinated plants—including trees, grasses, and weeds—produce most of the pollen that affects seasonal allergy sufferers. Wind-pollinated plants produce great amounts of pollen grains that are very small in size. For example, one ragweed plant…

Researchers are learning more about how plants respond to "alarm signals" released by other plants that are under attack by herbivores. To warn conspecifics about predators, many animals issue alarms by vocalizing or emitting odors. In the case of…

To bolster food security in a warming world, engineers are developing a coating that could better protect seeds, such as beans, from drought in semiarid regions. The coating mimics a mucilage-based hydrogel produced naturally by some seeds, such as…

Genealogists and anthropologists have long disputed the provenance of domestic dogs (Canis lupus familiaris). Although genetic analyses and fossil evidence indicate that the domestic dog descended from the gray wolf (Canis lupus), the exact location…

Approximately 75% of flowering plants—including about a third of agricultural food crops—depend on the distribution of pollen by an array of animals known collectively as pollinators. These animals include insects such as bees and wasps…

The diverse totality of microorganisms regularly found on and in the human body is collectively referred to as the human microbiota or microbial flora, with the largest microbial community in the body residing in the large intestine, or colon.…

In the future, will global demand for coffee outstrip supply? The International Coffee Organization thinks so, based on droughts in Central America, crop-destroying freezing weather in Brazil, and global climate change. In general, coffee is a very…

According to the Intergovernmental Panel on Climate Change (IPCC), to avoid the major impacts of climate change, such as deadly heat and decreased crop yields, will require limiting global warming to a maximum increase of 1.5 to 2.0 degrees Celsius.…

Forest fires are becoming more problematic across the globe. For example, climate change has extended fire season in the United States by about 80 days since 1970 because of extreme weather events, such as prolonged drought, according to the U.S.…

The fossil record of sharks (members of the subclass Elasmobranchii within the class Chondrichthyes, or cartilaginous fishes) dates back more than 420 million years. Over the course of this time, sharks have been among the top predators found in the…

An investigation of 890-million-year-old limestone rocks excavated from the mountains of Canada's Northwest Territories has revealed possible evidence of the oldest animal life on Earth. Prior to this study, the oldest undisputed fossils of animal…

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,…

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…

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…

The earliest representatives of modern humans—those belonging to Homo sapiens—evolved from more archaic humans approximately 150,000–300,000 years ago in eastern Africa. During succeeding years, the geographical range of anatomically modern humans…

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…

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…

Overwhelming fossil evidence of dinosaurs indicates that these reptiles inhabited terrestrial environments and were initially bipedal (two-footed). Then, as dinosaurs evolved, some became quadrupedal, walking on four legs. Other ancient nondinosaur…

Stellar explosions known as supernovae may be behind several anomalous rises in radiocarbon captured in tree rings over the past 40,000 years, according to a recent study that adds mounting evidence to the hypothesis that supernovae can impact…

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…

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…

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…

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…

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…

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…

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…

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 bacteria that live in the gut (gastrointestinal tract) constitute a large part of an individual's microbiome (also known as microbiota). In general, gut bacteria, also referred to as the microbial flora of the gut, are harbored by normal,…

Psychedelic drugs, also termed hallucinogenic or psychotomimetic drugs, induce transient states of altered perception resembling or mimicking the symptoms of psychosis and are characterized by profound alterations in mood. Because psychedelic drugs…

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…

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…

The World Health Organization (WHO) is planning to recognize gaming disorder as a mental health disease in 2018. The 11th revision of the WHO's International Classification of Diseases (ICD), which is a major worldwide reference for epidemiological,…

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…

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…

Autism, also known as autism spectrum disorder (ASD), is a complex neurodevelopmental condition that impairs the way that a person relates to and communicates with other people. In addition, autism is characterized by restricted, repetitive, or…

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…

In early 2018, NASA announced that it had demonstrated a new type of celestial navigation for the first time. Called XNAV, for x-ray pulsar-based navigation, it relies on beams of radiation from pulsars—the cinders of exploded, massive stars. As…

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…

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…

People consider visual perception to be one of the most trustworthy means of gathering information about the world. However, striking limitations in visual processing occur daily, distorting the precision and completeness of the visual experience…

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…

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…

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…

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…

Traditionally, the lowest-pitched (bass) instruments have provided the rhythmic foundation in musical ensembles. Researchers from McMaster University, Hamilton, Ontario, Canada, reporting in the Proceedings of the National Academy of Sciences (June…

Scientists from IBM and Sony Storage Media Solutions Corporation have jointly developed a magnetic storage tape with 20 times the storage capacity (areal density) of currently available tape. The record-setting tape, reported in IEEE Transactions on…

Tiny granules found within the pollen sacs of numerous species of flowers may play a key role in allergic reactions associated with pollen. Measuring less than 4 micrometers (μm) in diameter (most being less than 1 μm), these granules are called…

The continuing development of quantum computing, a potentially revolutionary form of number-crunching, has reached a new milestone. Earlier this month, IBM announced the building of a prototype 50-qubit processor for the company’s quantum cloud…

New regulations by the U.S. Food and Drug Administration (FDA) that went into effect on January 1, 2017, banned the use of antibiotics as feed supplements to help livestock and poultry grow faster. The new rules, prohibiting the over-the-counter…

Because of nutrient-poor soil and the high cost of fertilizer, farmers in parts of Africa often produce only one-fifth to one-tenth as much corn (maize) per hectare as farmers in the United States do. Over time, farming in Africa and elsewhere in…

Visitors to websites may think their visits are anonymous, but digital techniques can reveal their identities to site operators and track their movements online more revealingly than they realize. Web fingerprinting, also known as device…

Wildfires are known to emit large amounts of gaseous and particulate pollutants. In an effort to identify and quantify these pollutants, researchers took their instruments to the skies where they sampled and analyzed smoke plumes from aircraft…

A magnitude 5.1 nuclear test was detected 376 km (234 mi) NE of Pyongyang, North Korea (DPRK) on January 6, 2015 at 10:30 a.m. local time (01:30 UTC), according to the U.S. Geological Survey (USGS). The event was picked up at seismic stations around…

Many trees enjoy extremely long lives in comparison to humans and other animals. Yet one group of trees, the bristlecone pines, stands out as the most ancient of all, with individual trees that commonly live for thousands of years, including one…

The study of the neural basis of animal behavior is known as neuroethology. It is a combination of two disciplines: neurobiology, the study of the nervous system, and ethology, the study of animal behavior. Neurobiology describes how the nervous…

Between 2004 and 2014, the total phosphorus content of lakes and streams in the contiguous (lower 48) United States rose, according to surveys by the U.S. Environmental Protection Agency (EPA) reported in the journal Environmental Science &…

Biochar is charcoal made from biomass (organic matter used for energy). A process called pyrolysis, in which biomass is heated to high temperature in the absence of oxygen, produces biochar along with combustible gases (syngas) and oils (bio-oils).…

Concrete and steel have been the materials of choice for constructing high-rise buildings for over 100 years. Definitions of high-rise buildings vary, but according to the U.S. National Fire Protection Association high-rise buildings are 23 meters…

In the Rising Star cave system in South Africa, located about 48 kilometers (30 miles) north of Johannesburg, paleoanthropologists have unearthed an extensive collection of more than 1550 skeletal elements from at least 15 individuals that have…

Much of coastal and southern California has a Mediterranean climate, which is characterized by cooler, wetter winters and hotter, drier summers. Only drought-resistant plant species can survive without irrigation in this type of climate. Turf grass,…

In the Afar region of Ethiopia, paleoanthropologists unearthed a 2.8 million-year-old jawbone (mandible) that was provisionally assigned to the genus Homo [the genus of human beings, including modern humans (Homo sapiens) and other extinct species].…

The biflagellate water molds, downy mildews, and other microorganisms classified as members of the Oomycota (also termed Oomycetes) have long puzzled taxonomists. Previously, investigators thought them to constitute a group within the true fungi…

Two varieties of apples that have been genetically engineered not to turn brown when cut or bruised were cleared in February and March of 2015 for growth and sale in Canada by the Canadian Food Inspection Agency (CFIA) and Health Canada (HC) and in…

The use of certain insects to attack and destroy pests—predominantly other insects—is an intriguing and increasingly popular natural method of biological insect control. In particular, the ichneumon wasp is employed for this purpose to control pest…

Woolly mammoths (Mammuthus primigenius) once inhabited most of Europe and the northern halves of North America and Asia during the Late Pleistocene Epoch. Dating back to approximately 400,000 years ago, these members of the mammalian order…

The olive tree (Olea europaea) is an ancient cultivated plant that was originally domesticated by early civilizations in the eastern Mediterranean regions. Today, the major olive-producing countries are Spain, Italy, Greece, and Turkey, which…

An artificial leaf is a solar cell that uses water and an electrical current generated from sunlight to produce hydrogen (for fuel) and oxygen. It is currently in development at laboratories worldwide. If successful, the artificial leaf could serve…

One of the most remarkable features of the sea (marine) turtles that inhabit the tropical and subtropical waters of the world is their homing ability. Throughout the year, sea turtles swim huge distances, often more than 1600 kilometers (1000…

The flow of pedestrians through public spaces and thoroughfares is frequently a concern of architects, engineers, and planners, as well as building owners and operation managers, who may want to identify potential traffic bottlenecks, reduce…

One of history’s worst agricultural catastrophes was the great Irish potato famine of 1845–1849, which killed more than a million people in Ireland, forced the emigration of 1.5 million others, and fueled resentments between the Catholic and…

The evolutionary ancestry of the modern human race became even more complicated in 2012 with the results of studies on DNA extracted from bits of 50,000-year-old bone from Siberia. The analysis confirmed that an archaic species of people called…

Dogs belong to the mammalian family Canidae. Members of this carnivorous group comprise domestic dogs, wolves, wild dogs, coyotes, dingoes, foxes, and jackals. Canis lupus familiaris (also referred to as Canis familiaris) is the species name given…

Despite the cost-saving advantages of low maintenance and high fuel economy, most battery-powered electric vehicles (EVs) have a limited driving range of about 80 miles (130 kilometers). Not surprisingly, one of the biggest obstacles to consumer…

Ethylene, CH2=CH2, the most-produced organic chemical in the world, is used to make hundreds of products. The major product is polyethylene, but other important ones include poly(vinyl chloride), polystyrene, antifreeze (ethylene glycol), adhesives,…

Researchers from the Massachusetts Institute of Technology (MIT), in collaboration with industry partners Stratasys and Autodesk, have used 3D printing technology to create objects that can self-assemble into new structures when desired. The process…

The origin, evolutionary history, and extinction of the Neandertals (Homo neanderthalensis, a group of late archaic humans from Europe, southwest Asia, and central Asia that immediately preceded the first modern humans in those regions), as well as…

Marijuana is the Spanish-derived name for the dried leaves, stems, seeds, and flowering tops of the hemp plant (Cannabis sativa). For thousands of years, humans have consumed marijuana (in edible, smokeable, and vaporized forms) because of its…

Papaya (Carica papaya) is a major fruit crop cultivated in tropical and subtropical regions. The treelike, herbaceous papaya plant grows quickly and typically reaches a height of 6–9 meters (20–30 feet). The commercially important fruits cluster…

Soil organic matter represents a reservoir of stored (sequestered) carbon that slowly cycles between the earth and the atmosphere. It is predominately composed of humus stabilized by clay particles, with the remainder being less stable decaying…

The historical use of medicinal mushrooms in the traditional therapies of East Asia has been documented for millennia, and biomedical science is now seeking to validate this ancient mycological knowledge through more rigorous evaluation and testing…

Of all the air pollutants, one of the most dangerous to human health is fine-particulate matter (PM2.5)—solid or liquid particles less than 2.5 micrometers in diameter. The health risk for PM2.5 is that these particles can be inhaled deep into the…

Tannins (tannic acids) are naturally occurring complex chemicals found in plants. These proanthocyanidin polyphenols are particularly prevalent in a variety of vascular plants, including fruits (especially grapes), teas, legumes, and grasses.…