After a summer that tied for the country's hottest, meteorologists say an unusually warm autumn is delaying snowfall

Introduced in 1934, the federal duck stamp contest has raised more than $1.2 billion and protected at least 6.5 million acres across the nation. Now, an art exhibition at Connecticut’s Bruce Museum honors the competition’s history

The deep penetrations suggest that the feline was pressing its claws into the clay, a behavior sometimes known as "making biscuits"

A new exhibition spotlights the Spanish artist's printmaking talents, which he began honing in his 20s. In the decades that followed, he produced thousands of breathtaking creations

A "staggering array" of markings have been hiding in plain sight carved into the walls of Gainsborough Old Hall, a 500-year-old home in Lincolnshire, England

The species may have been carried to the Sacramento–San Joaquin Delta in ballast water on ships

Born October 30 to parents Gloria and Otto at the Edinburgh Zoo in Scotland, the hippo is already gaining popularity, following in the footsteps of viral sensation Moo Deng

When the war ended, Allied soldiers tracked down Nicolas de Largillierre's "Portrait de femme à mi-corps" with the help of a savvy French curator who had been working for the resistance

Antonia, a cloned black-footed ferret at the Smithsonian's National Zoo and Conservation Biology Institute, has produced two healthy offspring that will help build genetic diversity in their recovering population

In a rare technique among mammals, the bats burn proteins from blood, rather than carbs or fat, to power their pursuits of prey, according to a new study

Steve Lazarides' personal collection of prints, original works, handwritten press releases and burner phones sold at auction for around $1.4 million

This story and others have come to light during a project to translate and digitize a series of texts about archbishops in York, England

‘Our goal is to provide full flexibility, 24/7,’ one resident said. ‘If you want to cut the lawn at 4 a.m., then you do it.’

It's not clear how the juvenile male ended up so far north, but experts suggest he was motivated by his appetite

During a release of captive-bred snails in September, researchers discovered wild-born individuals from the Partula tohiveana species—which had been considered extinct in the wild—marking a huge milestone in a global effort to save them

Sławomir and Szymon Milewski were searching for a Roman road when they stumbled upon the cache of coins, which is worth more than $120,000

Cenotes in the Yucatán Peninsula are time capsules preserving remnants of Maya culture and fossils of extinct megafauna

In the late 19th century, city officials turned the final resting place for 10,000 souls into what's now Greenwich Village’s James J. Walker Park

Once one of the world’s most dangerous border crossings, Berlin's symbol of death and division has been turned into a tangible way to experience history

You asked, we answered

These grounded planes in the Congo have captured the imagination of these children

Iconic images of Dr. King from the Smithsonian collection

"Fascinating, Captain"

The surge of hungry four-legged visitors to Belushya Guba is part of a larger trend

A new book charts the history of pet cemeteries and honors the universal experience of grieving an animal companion

Renaissance paintings, medieval archives, cloistered orchards—how one Italian scientist is uncovering secrets that could help combat a growing agricultural crisis

A century on, the country’s most beloved Thursday spectacle reaches new heights

These images from the Smithsonian Magazine Photo Contest show how communities in Mexico and beyond mark Día de los Muertos.

The terms “snake oil” and “snake-oil salesperson” are part of the vernacular thanks to Clark Stanley, a quack doctor who marketed a product for joint pain in the late 19th century

Shallaway Youth Choir is bringing a program of music to the Basilica in downtown St. John’s on Remembrance Day. Artistic director Kellie Walsh says the choir will sing about such topics as the Unknown Soldier and schoolchildren who care for Newfoundland graves in London. Where Once They Stood will be performed at 2 p.m. and 7 p.m. on Monday.

Monday marks the first Remembrance Day ceremony at the National War Memorial in St. John's to include the tomb of the Unknown Soldier. We're proud to present again two documentaries that tell a remarkable story.

Large crowds came together at city hall in Corner Brook to lay wreaths and honour veterans on Monday. The ceremony portion was completed with a playing of the Last Post.

A Labrador foster parent and head of a group working to better the Labrador foster care system is stressing the importance of keeping Indigenous children with Indigenous parents in their Indigenous communities.

Hundreds congregated in downtown St. John's Monday morning to pay tribute to Newfoundland and Labrador's fallen soldiers, and honoured the dead for the first time at the newly refurbished National War Memorial and tomb of the Unknown Solider. 

People using the library in the Arts and Culture Centre in St. John's are being forced to use alternate entrances due to an unsafe staircase in front of the building.

A researcher studying the rise of extremism in Atlantic Canada warns Ku Klux Klan Halloween costumes are just one example of an insidious effort by far-right groups to normalize hateful attitudes.

The L'nu Sipuk Kina'muokuom school observed Indigenous Veterans Day with an event on Friday. Students, faculty and staff got together to honour Mi’kmaw military veterans and RCMP members.

A Port Hawkesbury woman has long imagined a Remembrance Day with her great-uncle's war medals. It will happen this year for the first time thanks to some sleuthing and the kindness of her great-uncle's foster family.

About a thousand people stood solemnly in the rain at a cenotaph in downtown Halifax on Monday morning to pay tribute to veterans on Remembrance Day.

As Nova Scotia politicians make their fall election promises, Julie Leggett is urging them to commit to helping people on income assistance stay cool during heat waves.

The Société de transport de Montréal (STM) has established a non-urgent text line for transit users to signal security issues in the Metro network.

Two Falls (Nishu Takuatshina) was developed in Montreal by a local studio that collaborated closely with Indigenous designers and consultants.

Amid rapid global advances and deployment of artificial intelligence technologies, the federal government has invested millions to combine the minds of three existing institutes into one that can keep an eye on potential dangers ahead.

Mosquitoes take blood meals from a diverse range of host animals and their host associations vary by species. Characterizing these associations is an important element of the transmission dynamics of mosquito-vectored pathogens. To characterize mosquito host associations, various molecular techniques have been developed, which are collectively referred to as blood meal analysis. DNA barcoding has diverse biological applications and is well-suited to mosquito blood meal analysis. The standard DNA barcoding marker for animals is a 5' fragment of the cytochrome c oxidase I (COI) gene. A major advantage of this marker is its taxonomic coverage in DNA sequence reference databases, making it feasible to identify a wider range of mosquito host species than with any other gene. However, the COI gene contains high sequence variation at potential priming sites between vertebrate orders. Coupled with the need for primer sequences to be mismatched with mosquito priming sites so that annealing to mosquito DNA is inhibited, it can be difficult to design primers suitable for blood meal analysis applications. Several primers are available that perform well in mosquito blood meal analysis, annealing to priming sites for most vertebrate host taxa, but not to those of mosquitoes. Because priming site sequence variation among vertebrate taxa can cause amplification to fail, a hierarchical approach to DNA barcoding-based blood meal analysis can be applied. In such an approach, no single primer set is expected to be effective for 100% of potential host species. If amplification fails in the initial reaction, a subsequent reaction is attempted with primers that anneal to different priming sites, and so on, until amplification is successful.

Mosquito species vary in their host associations. Although some species are relative generalists, most specialize, to varying extents, on particular types of host animals. Mosquito host associations are among the most important factors that influence the transmission dynamics of mosquito-vectored pathogens, and understanding these associations can provide insight on how such pathogens move within ecosystems. Characterization of the host associations of mosquito species requires applying blood meal analysis to the largest possible sample size of mosquito blood meals. Processing large samples of mosquito blood meals can be time-consuming, especially when chain-termination sequencing is used, necessitating individual processing of each specimen. Various methods and commercially available kits and products are available for extracting DNA from mosquito blood meals. The hot sodium hydroxide and Tris (HotSHOT) method is a rapid and inexpensive method of DNA extraction that is compatible with the recovery of DNA from mosquito blood meals preserved on QIAcard Flinders Technology Associates (FTA) Classic Cards (FTA cards). FTA cards allow nucleic acids found in blood meals to be preserved easily, even in field conditions. DNA prepared using this method is suitable for polymerase chain reaction (PCR)-based blood meal analysis.

All PCR- and DNA-based blood meal analyses require host DNA from a mosquito blood meal to be effectively preserved between the time when the specimen is collected and the extraction of DNA. As soon as a mosquito ingests blood from a host animal, digestion of host cells and cellular components within the blood meal by enzymes in the mosquito midgut begins to degrade the host DNA templates that are the targets of polymerase chain reaction (PCR) amplification. Without effective preservation, host DNA is typically undetectable by PCR 48 h after feeding, because of digestion. Preservation methods for mosquito blood meals vary in their efficacy, and the logistics of fieldwork can limit the options for preservation of blood meals and maintenance of the integrity of host DNA. This protocol describes a method of blood meal preservation that is effective, convenient, and amenable to fieldwork in remote locations where cryopreservation at –20°C or –80°C may not be feasible. It uses a Flinders Technology Associates (FTA) card, which is a chemically treated card that lyses cells and allows nucleic acids to be preserved. This method is also expected to preserve the DNA or RNA of pathogens present within the engorged mosquito abdomen, including RNA viruses.

The insect eggshell is a multifunctional structure with several important roles, including generating an entry point for sperm via the micropyle before oviposition, serving as an oviposition substrate attachment surface, and functioning as a protective layer during embryo development. Eggshell proteins play major roles in eggshell tanning and hardening following oviposition and provide molecular cues that define dorsal–ventral axis formation. Precise eggshell formation during ovarian follicle maturation is critical for normal embryo development and the synthesis of a defective eggshell often gives rise to inviable embryos. Therefore, simple and accurate methods for identifying eggshell proteins will facilitate our understanding of the molecular pathways regulating eggshell formation and the mechanisms underlying normal embryo development. This protocol describes how to isolate and enrich eggshells from mature oocytes of Aedes aegypti mosquitoes and how to extract their eggshell proteins for liquid chromatography with tandem mass spectrometry (LC–MS/MS) proteomic analysis. Although this methodology was developed for studying mosquito eggshells, it may be applicable to eggs from a variety of insects. Mosquitoes are ideal model organisms for this study as their ovarian follicle development and eggshell formation are meticulously regulated by blood feeding and their follicles develop synchronously throughout oogenesis in a time-dependent manner.

Transposon-mediated transgenesis has revolutionized both basic and applied studies of mosquito vectors of disease. Currently, techniques such as enhancer traps and transposon tagging, which rely on remobilizable insertional mutagenesis, are only possible with transposon-based vector systems. Here, we provide general descriptions of methods and applications of transposon-based mosquito transgenesis. The exact procedures must be adapted to each mosquito species and comparisons of some differences among different mosquito species are outlined. A number of excellent publications showing detailed and specific protocols and methods are featured and referenced.

After more than a century of searching, scientists have discovered a gene in snails that may control asymmetries inside many animals