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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…

Neuroscientists have long sought to explain how the brain correctly recognizes a stimulus despite the stimulus appearing under different circumstances with widely variable external factors. For example, with regard to olfactory stimuli, humans can…

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…

Studies have shown that all classes of vertebrates—and even some invertebrate species—have the cognitive ability to discriminate among different quantities. For example, many kinds of studied animals can distinguish specific numbers of objects in…

Among the non-human animals that can be infected with—and become sick from—humans who have the SARS-CoV-2 virus that causes COVID-19 are deer, mink, hyenas, pigs, ferrets, dogs, cats, and primates such as rhesus macaque monkeys, baboons, and…

Food packaging prevents contamination and extends the shelf-life of food products, making food safe and available to the public. Common food-packaging materials include metals, glass, paper, and plastics. Of these, metals, glass, and recyclable…

Monarch butterflies (Danaus plexippus) exclusively consume milkweed plants (genus Asclepia) both for nutrition and to help deter predators. Milkweed plants contain toxins that accumulate in the butterfly larva, or caterpillars, as the insects feed;…

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…

Food waste occurs at all levels of the supply chain and beyond, from farm to table, for reasons ranging from spoilage to over-buying. The U.S. Department of Agriculture’s (USDA) Economic Research Service defines food waste as “the edible amount of…

Pasta comes in various sizes and shapes, ranging from long and flat (such as linguine and spaghetti) to short types in the shape of shells (conchiglie), corkscrews (fusilli), and many others. Shaped pastas contain a larger volume of air, resulting…

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…

In many animals, including humans, the sense of smell performs an important threat-detection function by helping to identify potential sources of harm, such as rotting food and toxic fumes. Little is known, however, about the initial neural…

A new mathematical approach called emulation dramatically decreases the amount of time necessary to solve equations describing key properties of atomic nuclei. The approach will help physicists run simulations far more quickly—and without the need…

The American bald eagle (Haliaeetus leucocephalus) was once on the brink of extinction in North America. As a result of concerted conservation efforts, including the elimination of use of the pesticide DDT in the United States in 1972, the bald…

The taxonomic classification of whales continues to evolve as marine biologists glean new insights from investigations of the largest of all animals on Earth. Two recent whale discoveries—one concerning a new species, and the other dealing with…

The field of vaccination has been enhanced significantly by the successful development of two approved vaccines based on messenger RNA (mRNA) technologies. Prior to the COVID-19 pandemic that spread from China in 2019 to the rest of the world in…

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…

After a 203-day journey covering 472 million kilometers (293 million miles), NASA's Perseverance rover successfully landed on Mars on February 18, 2021. Perseverance is the largest and most sophisticated machine to ever land on another world.…

On April 7, 2021, the U.S. Centers for Disease Control and Prevention (CDC) announced that a genetic variant of SARS-CoV-2—the coronavirus that causes COVID-19—that was initially identified in the United Kingdom is the dominant form of the virus…

In response to the COVID-19 (coronavirus disease 2019) pandemic—which has dramatically affected the entire world, causing high morbidity, mortality, and massive social and economic disruption—and in addition to finding efficacious treatments for…

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…

With a fossil record dating to the start of the Mesozoic era, approximately 250 million years ago, the tuatara (Sphenodon punctatus) is the sole extant representative of the reptilian order Rhynchocephalia. This unique reptile has an unusually long…

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…

Scientists have suggested a possible connection between ancient Neandertals (Homo neanderthalensis) and the severity of disease in patients affected by COVID-19. In short, certain genes acquired from Neandertals during instances of interbreeding…

There has been substantial progress in the fight against certain drug-resistant organisms that cause serious, often fatal, diseases. However, two drug-resistant microbes—specifically, Candida auris (a fungal yeast) and Acinetobacter (a genus of…

Sickle cell disease, also termed sickle cell anemia, is a genetic disorder in which hypoxia, or oxygen deprivation, causes red blood cells (erythrocytes) to assume a rigid sickle shape, blocking blood flow within blood vessels. The disease results…

Fingerprint identification is a widely used forensic method for linking an individual to a crime scene. Investigators at a crime scene can find invisible (latent) fingerprints, which consist of natural skin oils, by "dusting" surfaces with carbon…

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…

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…

Over thousands of years of study of the human body through dissection and, more recently, modern-day imaging techniques, scientists have observed and analyzed various glands—that is, structures or organs that produce and secrete a substance or…

In a surprising find, researchers have detected phosphine (PH3) in the atmosphere of Venus. This poisonous, colorless, flammable gas is nonetheless considered a strong sign of life, or "biosignature." Biosignatures are gases or combinations of gases…

Over the course of history, smallpox has been among the most feared diseases of humankind. Caused by the variola virus (a DNA-containing member of the Poxviridae family) and spread by transfer through respiratory droplets during face-to-face…

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…

Occurring in mammary glands and closely associated tissues, breast cancer is the most common cancer observed in women. For example, in the United States, approximately 1 in 8 women (about 12%) will develop invasive breast cancer over the course of…

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…

Poliomyelitis, more commonly called polio, is a devastating infectious disease of the central nervous system caused by the poliovirus (a type of enterovirus), which has three types in the wild (types 1, 2, and 3). Wild types 2 and 3 were declared…

The Ebola virus comprises a group of pathogenic agents that cause severe and deadly hemorrhagic fevers in humans and other primates. During 2014 and 2015, an Ebola virus epidemic in West Africa—predominantly, the countries of Guinea, Liberia, and…

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…

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…

A compound found in cranberries, called cranberry proanthocyanidin (cPAC), when used in combination with antibiotics, such as tetracycline, prevents resistance to antibiotics in Escherichia coli and Pseudomonas aeruginosa, according to researchers…

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…

Fentanyl is a synthetic opioid analgesic (pain reliever) that resembles morphine in its action. However, its drug potency is approximately 50 to 100 times more powerful than that of morphine, leading to high rates of both addiction and overdose…

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…

The four main blood types (blood groups) found in humans are A, B, AB, and O. Two particular antigens (A and B) determine the specific blood type—A antigen is present in type A blood; B antigen is present in type B blood; both A and B antigens are…

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…

Macular degeneration is the most prevalent cause of vision impairment and loss among people aged 55 years and older. Also termed age-related macular degeneration (AMD), this serious eye condition damages the macula, which is the most sensitive part…

Measles is a highly infectious and communicable disease that is most often contracted in childhood. The infective particle is a ribonucleic acid (RNA) virus—specifically, a paramyxovirus belonging to the genus Morbillivirus. Infected individuals…

Caused by the rod-shaped bacterium Mycobacterium tuberculosis and transmitted by airborne droplets from a diseased individual, tuberculosis (TB) is a chronic infectious disease of humans (and other animals) that destroys body tissue. When M.…

Osteoprotegerin (OPG) is a protein that plays a central role in the regulation of bone mass. Also known as osteoclastogenesis inhibitory factor (OCIF), this naturally occurring protein [a soluble decoy receptor protein that belongs to the tumor…