These images from the Smithsonian Magazine Photo Contest capture quintessentially Cuban scenes

Eight years into living in Longyearbyen, on the Norwegian archipelago of Svalbard, I embrace the seasonal plunge into total darkness

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

Pedestrians in Montreal, Grand Rapids and other locations can time-travel thanks to installations that map historical scenes directly onto the cityscapes

These amazing images from the Smithsonian Magazine Photo Contest show the Arctic animals at their fierce but adorable best

Take a virtual tour through the streets and sights of England’s capital city with these stunning travel photos submitted to our photo contest

Get acquainted with the Big Apple’s major sights by browsing through these remarkable travel photos submitted to our photo contest

Getting the perfect shot requires great timing, the right equipment and nerves of steel

Iconic images of Dr. King from the Smithsonian collection

Michelle Frankfurter tells the stories of these young migrants and also those of the thousands who jump aboard “the death train”

From swirling aurora borealis to bioluminescent beaches, these award-winning photographs capture rare views of our world at night

See the finalists of our 2014 photo contest and vote for the Readers' Choice winner

It's curtains for the NASA mission's close relationship with the satellite

The tongues of bird-like dinosaurs and pterosaurs, however, may have been more mobile

As of last Wednesday, at least 3,500 sea turtles have been rescued from freezing waters in the midst record-breaking winter storm

In summer months above the North and South Poles, glowing clouds occasionally form naturally at sunset under the right conditions

In a twist befitting its pages, the satirical, anti-establishment publication that delivered laughs and hijinks to generations of young readers gets the respect it always deserved with a new museum exhibition

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

It’s easy to write bugs off as pests, but consider the ways in which they have positively impacted our lives

Adverse weather has cancelled ferry crossings between Newfoundland and Labrador and Nova Scotia heading into the long weekend.

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.

Newfoundland filmmaker Justin Simms is releasing his latest film called Sons. It was prompted by the birth of his son and left him wondering how traditional masculine behaviour is learned.

Police have reported that a man was fatally electrocuted in Torbay on Saturday evening. Two others are being treated for injuries.

Bombardier control box recovered during second dive to a World War 2 bomber at the bottom of Gander Lake.

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.

Have a photo you'd like us to see? Email us! Our address is nlphotos@cbc.ca.

The 50th Christmas Craft Fair gathered over a hundred vendors and thousands of customers in Torbay over the weekend. One family business was inspired by the early years of the fair and a passion to keep traditional crafts in style.

A woman who says she was repeatedly denied emergency care last spring is blasting the Newfoundland and Labrador health-care system, saying she’s been left psychologically scarred after being told several times that her gangrenous appendix was simply anxiety or constipation.

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.

Volunteers will be cutting hair at a salon based inside a Cape Breton food bank. The goal is to provide clients with the same salon experience paying customers would receive.

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.

RCMP are investigating after officers discovered human remains in an abandoned, burned vehicle in Greenhill, N.S.

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.

Some Nova Scotia municipal leaders are defending a funding stream the federal Conservatives say they will cut if elected, calling it a "game changer."

Building highways isn't the only solution to the growing problem of traffic congestion in and around the Halifax Regional Municipality, says the head of an organization that advocates for rail-based public transit.

The new mayor and council are planning big changes for the Cape Breton Regional Municipality, and one of those is at the top of the staff organizational chart now that chief administrative officer Marie Walsh is set to retire.

The Montreal English Theatre Awards ceremony is being held this evening at Le Gesù theatre. For the community, it's a time to celebrate their achievements and resilience coming out of the pandemic, together.

Dominic April fell in love with forging after his career in the military came to an end in 2015. Now operating a blacksmith studio near Quebec City, he hopes to help other veterans dealing with PTSD find creativity and purpose.

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

The City of Montreal wants to sell more land to community organizations, housing co-ops and other groups to build off-market housing. 

Quebec provincial police have confirmed that the body found in a Montreal nature park on Oct. 30 was that of kidnapping victim and cryptocurrency influencer Kevin Mirshahi.

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.

To understand the circuitry of the brain, it is often advantageous to visualize the processes of a single neuron or population of neurons. Identifying sites where a neuron, or neurons, originates and where it projects can allow a researcher to begin to map the circuitry underlying various processes, including sensory-guided behaviors. Furthermore, neural tracing allows one to map locations where processes terminate onto regions of the brain that may have known functions and sometimes to identify candidate upstream or downstream connections, based on proximity. Many methods of neural tracing are available; here, we focus on loading fluorescent dyes into a neuron (fluorescent dye filling). Different options for dyes exist to label neurites. Among the most versatile and easy to use are dextran amine–conjugated dyes. They fill neurons bidirectionally, not discriminating between anterograde or retrograde loading direction. Dye filling must be done in unfixed tissue, as the dye needs to move through the neurons; however, dextran amine conjugates are aldehyde-fixable and once cells have been fully loaded with dye the tissue can be fixed and subjected to immunostaining. Coupling neural tracing with immunofluorescence is a useful way to determine specific brain or ventral nerve cord (VNC) regions where a neuron projects. This protocol describes methods for loading dextran amine conjugated dyes into a sensory tissue in the mosquito to visualize sites of sensory neuron innervation in the central nervous system, as well as efferent projections to these structures. This protocol is described for Aedes aegypti, for which it was optimized, but it also works across a variety of insects.

Mosquito-borne disease is a major global public health issue. One path toward the development of evidence-based strategies to limit mosquito biting is the study of the mosquito nervous system—in particular, the sensory systems that drive biting behavior. The central nervous system of insects consists of the brain and the ventral nerve cord. Here, we describe a protocol for dissecting, immunofluorescent labeling, and imaging both of these structures in the mosquito. This protocol was optimized for Aedes aegypti and works well on Anopheles gambiae tissue. It has not been tested in other mosquito species, but we anticipate that it would work on a range of mosquitoes, and, if not, our protocol will provide a starting point from which to optimize. Notably, a limited number of antibodies cross-react with Ae. aegypti proteins. This protocol is intended for use with validated antibodies and can also be used to test new antibodies as they are generated. It has been successfully used to visualize protein tags, such as green fluorescent protein, that have been introduced into the mosquito to amplify or detect their presence.

Laboratory study of field-collected mosquitoes can allow researchers to better understand the ways variation within and among mosquito populations shapes burdens of mosquito-borne disease. The Anopheles gambiae complex comprises the most important vectors of malaria, but it can be challenging to keep in the laboratory. For some species of mosquitoes, especially An. gambiae, it is very difficult to bring viable eggs into the laboratory. Instead, it is preferable to collect larvae or pupae and then transport them as carefully as possible back to the laboratory. This simple protocol allows a researcher to start new laboratory colonies from larvae or pupae collected from natural breeding sites or proceed directly to their planned experiments. The use of natural breeding sites provides additional reassurance that the resulting colonies are representative of natural populations.

Laboratory study of natural populations of mosquitoes can play a key role in determining the underlying causes of variation in burdens of mosquito-borne disease. Aedes aegypti is the main vector of the viruses that cause dengue, chikungunya, Zika, and yellow fever, making it a high priority for laboratory study. Ae. aegypti eggs provide an ideal starting point for new laboratory colonies. Eggs can be collected using ovicups, which are small plastic cups lined with seed-germination paper and partially filled with leaf-infused H₂O. Once collected, dry eggs will remain viable for months and can be safely transported long distances back to the laboratory as long as they are properly stored. This protocol provides step-by-step instructions for preparing for collecting, storing, and hatching Ae. aegypti eggs and has successfully yielded laboratory colonies from locations across both the native and invasive range of this species.

In insects, gustatory neurons sense chemicals upon contact and directly inform many behaviors critical for survival and reproduction, including biting, feeding, mating, and egg laying. However, the taste sensory system is underexplored in many anthropophilic disease vectors such as mosquitoes, which acquire and transmit human pathogens during blood feeding from human hosts. This results in a big gap in vector biology—the study of organisms that spread disease by transmitting pathogens—because insect vectors closely interact with humans while selecting suitable individuals and appropriate bite sites for blood meals. Human sweat and skin-associated chemistries are rich in nonvolatile compounds that can be sensed by the mosquito's taste system when she lands on the skin. Taste sensory units, called sensilla, are distributed in many organs across the mosquito body, including the mouthparts, legs, and ovipositors (female-specific structures used to lay eggs). Each sensillum is innervated by as many as five taste neurons, which allow detection and discrimination between various tastants such as water, sugars, salts, amino acids, and plant-derived compounds that taste bitter to humans. Single-sensillum recordings provide a robust way to survey taste responsiveness of individual sensilla to various diagnostic and ecologically relevant chemicals. Such analyses are of immense value for understanding links between mosquito taste responses and behaviors to specific chemical cues and can provide insights into why mosquitoes prefer certain hosts. The results can also aid development of strategies to disrupt close-range mosquito–human interactions to control disease transmission. Here we describe a protocol that is curated for electrophysiological recordings from taste sensilla in mosquitoes and sure to yield exciting results for the field.

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.