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2453) Thomas Huckle Weller

Gist:

Work

Many infectious diseases are caused by viruses—very small biological particles. A virus lacks metabolism of its own and cannot multiply without infecting a living cell. For a long time the prevailing opinion was that viruses could not be cultured in a laboratory. However, in 1949 Frederick Robbins, John Enders, and Thomas Weller succeeded in culturing the virus that causes polio in human muscle and tissue in a laboratory setting. This became an important step on the road toward a vaccine against polio.

Summary

Thomas H. Weller (born June 15, 1915, Ann Arbor, Mich., U.S.—died Aug. 23, 2008, Needham, Mass.) was an American physician and virologist who was the corecipient (with John Enders and Frederick Robbins) of the Nobel Prize for Physiology or Medicine in 1954 for the successful cultivation of poliomyelitis virus in tissue cultures. This made it possible to study the virus “in the test tube”—a procedure that led to the development of polio vaccines.

After his education at the University of Michigan at Ann Arbor (A.B., 1936; M.S., 1937) and Harvard University (M.D., 1940), Weller became a teaching fellow at the Harvard Medical School (1940–42) and served in the U.S. Army Medical Corps during World War II. He was appointed assistant director of Enders’ infectious diseases laboratory at the Children’s Medical Center, Boston (1949–55), and, working with Enders and Robbins, soon achieved the propagation of poliomyelitis virus in laboratory suspensions of human embryonic skin and muscle tissue. He was also the first (with the American physician Franklin Neva) to achieve the laboratory propagation of rubella (German measles) virus and to isolate chicken pox virus from human cell cultures. Weller became professor of tropical public health at Harvard University in 1954 and from 1966 to 1981 served also as director of the Center for the Prevention of Infectious Diseases at the Harvard University School of Public Health. Weller’s autobiography, Growing Pathogens in Tissue Cultures: Fifty Years in Academic Tropical Medicine, Pediatrics, and Virology, was published in 2004.

Details

Thomas Huckle Weller (June 15, 1915 – August 23, 2008) was an American virologist. He, John Franklin Enders and Frederick Chapman Robbins were awarded a Nobel Prize in Physiology or Medicine in 1954 for showing how to cultivate poliomyelitis viruses in a test tube, using a combination of human embryonic skin and muscle tissue.

Biography

Weller was born and grew up in Ann Arbor, Michigan, where he graduated from Ann Arbor High School. He then went to the University of Michigan, where his father Carl Vernon Weller was a professor in the Department of Pathology. At Michigan, he studied medical zoology and received a B.S. and an M.S., with his masters thesis on fish parasites.

In 1936, Weller entered Harvard Medical School, and in 1939 began working under John Franklin Enders, with whom he would later (along with Frederick Chapman Robbins) share the Nobel Prize. It was Enders who got Weller involved in researching viruses and tissue-culture techniques for determining infectious disease causes. Weller received his MD in 1940, and went to work at Children's Hospital in Boston.

In 1942, during World War II, he entered the Army Medical Corps and was stationed at the Antilles Medical Laboratory in Puerto Rico, earning the rank of Major and heading the facility's Departments of Bacteriology, Virology and Parasitology. After the War, he returned to Children's Hospital in Boston, and it was there in 1947, that he rejoined Enders in the newly created Research Division of Infectious Diseases. After several leading positions, in July 1954, he was appointed head of the Tropical Public Health Department at the Harvard School of Public Health. Weller also served from 1953 to 1959 as director of the Commission on Parasitic Diseases of the American Armed Forces Epidemiological Board.

In addition to his work on polio, Weller also contributed to treating schistosomiasis, and Coxsackie viruses. He was also the first to isolate the virus responsible for chickenpox.

Awards

In 1954, Weller was awarded the George Ledlie prize in recognition of his research on rubella, polio and cytomegalovirus(CMV) viruses.

He was awarded the Nobel Prize in Physiology or Medicine in 1954 for his research on polio.

In 1996 he was awarded the Walter Reed Medal from the American Society of Tropical Medicine and Hygiene.

Personal life

In 1945, Weller married Kathleen Fahey, who died in 2011 aged 95. They had two sons and two daughters.

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2515) Baltic States

Gist

The Baltic states—Estonia, Latvia, and Lithuania—are three sovereign nations in Northern Europe on the eastern coast of the Baltic Sea. Gaining independence from the Soviet Union in 1991, they are now parliamentary republics, members of the EU, NATO, and the OECD, featuring high-income economies, high living standards, and a shared history.

The Baltic States receive their name from the Baltic Sea, which borders them. Lithuania, Estonia, and Latvia are bounded on the west and north by the Baltic Sea.

Summary

The Baltic states[a] or the Baltic countries is a geopolitical term encompassing Estonia, Latvia, and Lithuania. All three countries are members of NATO, the European Union, the Eurozone, and the OECD. The three sovereign states on the eastern coast of the Baltic Sea are sometimes referred to as the "Baltic nations", less often and in historical circumstances also as the "Baltic republics", the "Baltic lands", or simply the Baltics.

All three Baltic countries are classified as high-income economies by the World Bank and maintain a very high Human Development Index. The three governments engage in intergovernmental and parliamentary cooperation. There is also frequent cooperation in foreign and security policy, defence, energy, and transportation.

NATO:  North Atlantic Treaty Organization.
OECD: Organisation for Economic Co-operation and Development.

Geography

The Baltic States cover an area of 175,228 square kilometres (67,656 sq mi) (roughly twice the size of mainland Portugal), with a population of 6,132,500 (2024). Bordered by the Baltic Sea to the west and the north, they share borders with Russia, Belarus, and Poland. The Kaliningrad Oblast, formerly known as Königsberg in Germany, is landlocked between Lithuania and Poland and belongs to Russia.

The terrain of this region is relatively flat, punctuated by numerous lakes and ponds, particularly in the north, and hills in Lithuania.

General statistics

All three are unitary republics, which simultaneously joined the European Union on 1 May 2004, share EET/EEST time zone schedules and the euro currency.

EET: Eastern European Time.
EEST: Eastern European Summer Time.

Details

Baltic states are the northeastern region of Europe containing the countries of Estonia, Latvia, and Lithuania, on the eastern shores of the Baltic Sea.

The Baltic states are bounded on the west and north by the Baltic Sea, which gives the region its name, on the east by Russia, on the southeast by Belarus, and on the southwest by Poland and an exclave of Russia. The underlying geology is sandstone, shale, and limestone, evidenced by hilly uplands that alternate with low-lying plains and bear mute testimony to the impact of the glacial era. In fact, glacial deposits in the form of eskers, moraines, and drumlins occur in profusion and tend to disrupt the drainage pattern, which results in frequent flooding. The Baltic region is dotted with more than 7,000 lakes and countless peat bogs, swamps, and marshes. A multitude of rivers, notably the Neman (Lithuanian: Nemunas) and Western Dvina (Latvian: Daugava), empty northwestward into the Baltic Sea.

The climate is cool and damp, with greater rainfall in the interior uplands than along the coast. Temperatures are moderate in comparison with other areas of the East European Plain, such as in neighbouring Russia. Despite its extensive agriculture, the Baltic region remains more than one-third forested. Trees that adapt to the often poorly drained soil are common, such as birches and conifers. Among the animals that inhabit the region are elk, boar, roe deer, wolves, hares, and badgers.

The Latvian and Lithuanian peoples speak languages belonging to the Baltic branch of the Indo-European linguistic family and are commonly known as Balts. The Estonian (and Livonian) peoples, who are considered Finnic peoples, speak languages of the Finno-Ugric family and constitute the core of the southern branch of the Baltic Finns. Culturally, the Estonians were strongly influenced by the Germans, and traces of the original Finnish culture have been preserved only in folklore. The Latvians also were considerably Germanized, and the majority of both the Estonians and the Latvians belong to the Lutheran church. However, most Lithuanians, associated historically with Poland, are Roman Catholic.

The vast majority of ethnic Estonians, Latvians, and Lithuanians live within the borders of their respective states. In all three countries virtually everyone among the titular nationalities speaks the native tongue as their first language, which is remarkable in light of the massive Russian immigration to the Baltic states during the second half of the 20th century. Initially, attempts to Russify the Baltic peoples were overt, but later they were moderated as Russian immigration soared and the sheer weight of the immigrant numbers simply served to promote this objective in less-blatant ways. Independence from the Soviet Union in 1991 allowed the Baltic states to place controls on immigration, and, in the decade following, the Russian presence in Baltic life diminished. At the beginning of the 21st century, the titular nationalities of Lithuania and Estonia accounted for about four-fifths and two-thirds of the countries’ populations, respectively, while ethnic Latvians made up just less than three-fifths of their nation’s population. Around this time, Poles eclipsed Russians as the largest minority in Lithuania. Urban dwellers constitute more than two-thirds of the region’s population, with the largest cities being Vilnius and Kaunas in southeastern Lithuania, the Latvian capital of Riga, and Tallinn on the northwestern coast of Estonia. Life expectancy in the Baltic states is comparatively low by European standards, as are the rates of natural increase, which were negative in all three countries at the beginning of the 21st century, owing in part to an aging population. Overall population fell in each of the Baltic states in the years following independence, primarily because of the return emigration of Russians to Russia, as well as other out-migration to western Europe and North America. In some cases, Russians took on the nationalities of their adopted Baltic countries and were thus counted among the ethnic majorities.

After the breakup of the Soviet Union, the Baltic states struggled to make a transition to a market economy from the system of Soviet national planning that had been in place since the end of World War II. A highly productive region for the former U.S.S.R., the Baltic states catered to economies of scale in output and regional specialization in industry—for example, manufacturing electric motors, machine tools, and radio receivers. Latvia, for example, was a leading producer of Soviet radio receivers. Throughout the 1990s privatization accelerated, national currencies were reintroduced, and non-Russian foreign investment increased.

Agriculture remains important to the Baltic economy, with potatoes, cereal grains, and fodder crops produced and dairy cattle and pigs raised. Timbering and fisheries enjoy modest success. The Baltic region is not rich in natural resources. Though Estonia is an important producer of oil shale, a large share of mineral and energy resources is imported. Low energy supplies, inflationary prices, and an economic collapse in Russia contributed to an energy crisis in the Baltics in the 1990s. Industry in the Baltic states is prominent, especially the production of food and beverages, textiles, wood products, and electronics and the traditional stalwarts of machine building and metal fabricating. The three states have the highest productivity of the former constituent republics of the Soviet Union.

Shortly after attaining independence, Estonia, Latvia, and Lithuania abandoned the Russian ruble in favour of new domestic currencies (the kroon, lats, and litas, respectively), which, as they strengthened, greatly improved foreign trade. The main trading partners outside the region are Russia, Germany, Finland, and Sweden. The financial stability of the Baltic nations was an important prerequisite to their entering the European Union and the North Atlantic Treaty Organization in 2004. Estonia, Latvia, and Lithuania each adopted the euro as its common currency in 2011, 2014, and 2015, respectively.

This article covers the history of the region from antiquity to the post-Soviet period. Additional information on the region’s physical and human geography can be found in the article Europe. Area 67,612 square miles (175,116 square km). Pop. (2020 est.) 5,841,000.

Additional Information:

What are the Baltic States?

The term Baltic States refers to a group of independent countries that border the Baltic Sea. The Baltic States are composed of three countries: Lithuania, Estonia, and Latvia. Combined, the countries are no more significant in size than the state of Missouri.

The Baltic States or Baltic countries are located in the northeastern region of Europe. These countries gained independence from the Russian Empire in the 1910s and regained independence from the Soviet Union in the 1990s.

While the population of the Baltic states is quite small, each country has a major city as its capital: Tallinn in Estonia; Rīga in Latvia; and Vilnius in Lithuania. Each city has an old town, with historic buildings reflecting their German heritage. Rīga also has a large number of art nouveau buildings. The legacy of the Soviet Union is gradually being erased, although many Soviet-era apartment blocks remain. The capital cities are the seat of government, with many administrative offices in them. Economic activity is intense: Rīga and Tallinn are both important port cities, while Vilnius has emerged as a major financial center. In recent years, the Baltic capitals have become tourist destinations as foreigners have come to appreciate their attractions.

Song Traditions

One of the most significant cultural traditions in the Baltic states is the singing of folk songs, of which there are thousands. Traditional dance is also important. Children begin to learn singing and dance at an early age, often becoming part of ensembles that perform publicly. Mass song and dance festivals, involving tens of thousands of people, are held on a regular basis, with a great deal of audience participation. The importance of these festivals has been officially recognized by UNESCO, which declared them to be Masterpieces of the Oral and Intangible Heritage of Humanity. This year, many festivities, including folk singing and dancing, will be held in all three Baltic states as part of the celebration of the 100th anniversary of independence for Estonia, Latvia, and Lithuania. The tradition of song and dance festivals has been maintained by Baltic communities in the United States, Canada, and elsewhere.

Celebrating Nature

A reverence for nature has always been at the heart of traditional Baltic culture, and it continues in the present day. The celebration of the mid-summer solstice is one of the most important holidays on the calendar, and all three countries basically shut down for two days. People go to the countryside, where they build bonfires and sing songs until late in the night. The natural splendor of the Baltic countries was endangered by pollution and development in the Soviet period, but now environmental protection is a high priority. The region’s natural beauty is a primary attraction for visitors from all over the world.

Innovation and Development

The traditional economies of the Baltic countries were based on timber, dairy products, and agriculture. These all remain important, but after the end of the Soviet period, Estonia, Latvia, and Lithuania have undergone a major economic transformation as new sectors have been developed in the areas of computer software, electronics, and ICT (Information and Communications Technology) products. Of the three Baltic states, Estonia has taken the lead in this process, with its development of commercial services such as Skype and governmental programs related to building e-society infrastructure. Latvia and Lithuania have also invested heavily in the electronics sphere. All three Baltic countries have developed close connections with Silicon Valley, with many Baltic companies basing their operations here. It is likely that e-commerce will continue to grow in the Baltic states as their highly educated professional classes make more innovations.

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2514) Arctic Wolf

Gist:

Do Arctic wolves still exist?

They were listed as vulnerable from 1982 to 1995, but their status was upgraded to least concern in 1996 and has remained the same ever since. Thanks to their remote, icy habitat, Arctic wolves live far away from any human populations.

Are Arctic wolves friendly to humans?

The Arctic wolf is relatively unafraid of people, and can be coaxed to approach people in some areas.

Summary

The Arctic fox (Vulpes lagopus), also known as the white fox, polar fox, or snow fox, is a small species of fox native to the Arctic regions of the Northern Hemisphere and common throughout the Arctic tundra. It is well adapted to living in cold environments, and is known for its thick, warm fur that can be used as camouflage against snow in the winter. It has a large and fluffy tail. In the wild, most individuals do not live past their first year but some exceptional ones survive up to 11 years. Its body length ranges from 46 to 68 cm (18 to 27 in), with a generally rounded body shape to minimize the escape of body heat.

The Arctic fox preys on many small creatures such as lemmings, voles, ringed seal pups, fish, waterfowl, and seabirds. It also eats carrion, berries, seaweed, and insects and other small invertebrates. Arctic foxes form monogamous pairs during the breeding season and they stay together to raise their young in complex underground dens. Occasionally, other family members may assist in raising their young. Natural predators of the Arctic fox include golden eagles, Arctic wolves, polar bears, wolverines, red foxes, and brown bears.

Details

The Arctic wolf (Canis lupus arctos), also known as the white wolf, polar wolf, and the Arctic grey wolf, is a subspecies of grey wolf native to the High Arctic tundra of Canada's Queen Elizabeth Islands, from Melville Island to Ellesmere Island. Unlike some populations that move between tundra and forest regions, Arctic wolves spend their entire lives north of the northern treeline. Their southward distribution is limited to the northern fringes of the Middle Arctic tundra on the southern half of Prince of Wales and Somerset Islands.

It is a medium-sized subspecies, distinguished from the northwestern wolf by its smaller size, whiter colouration, narrower braincase, and larger carnassials. Since 1930, there has been a progressive reduction in size in Arctic wolf skulls, which is likely the result of wolf-dog hybridization.

Taxonomy

In 1935, the British zoologist Reginald Pocock attributed the subspecies name Canis lupus arctos (Arctic wolf) to a specimen from Melville Island in the Queen Elizabeth Islands, Canada. He wrote that similar wolves could be found on Ellesmere Island. He also attributed the name Canis lupus orion to a Greenland wolf specimen from Cape York, northwest Greenland. Both wolves are recognized as separate subspecies of Canis lupus in the taxonomic authority Mammal Species of the World (2005).

A study by Chambers et al. (2012) using autosomal microsatellite DNA and Mitochondrial DNA data indicate that the Arctic wolf has no unique haplotypes which suggests that its colonization of the Arctic Archipelago from the North American mainland was relatively recent, and thus not sufficient to warrant subspecies status. During a meeting assembled in 2014 by the National Center for Ecological Analysis and Synthesis of the United States Fish and Wildlife Service, one speaker, Robert K. Wayne, mentioned he disagreed with the conclusion that a subspecies had to be genetically distinct, believing that different subspecies could slowly grade into each other - suggesting that although it was impossible to determine if an individual wolf was one subspecies or the next using DNA, the population of Arctic wolves as a whole could be distinguished by the looking at the proportions of single-nucleotide polymorphisms (SNP): i.e. Arctic wolves could be distinguished by having three wolves in the putative population with a specific SNP, whereas another subspecies could be distinguished by having 20 wolves with that SNP. Wayne furthermore stated that he believed the habitat in which the wolf happened to be found was a good enough characteristic to distinguish a subspecies.

Behaviour

The Arctic wolf is relatively unafraid of people, and can be coaxed to approach people in some areas. The wolves on Ellesmere Island do not fear humans, which is thought to be due to them seeing humans so little, and they will approach humans cautiously and curiously. Otto Sverdrup wrote that during the Fram expedition, a pair of wolves shadowed one of his teammates, who kept them at a distance by waving his ski pole. In 1977, a pair of scientists were approached by six wolves on Ellesmere Island, with one animal leaping at one of the scientists and grazing a cheek. A number of incidents involving aggressive wolves have occurred in Alert, Nunavut, where the wolves have lived in close proximity to the local weather station for decades and became habituated to humans. One of these wolves attacked 3 people, was shot, and tested positive for rabies.

Very little is known about the movement of the Arctic wolves, mainly due to climate. The only time at which the wolf migrates is during the wintertime when there is complete darkness for 24 hours. This makes Arctic wolf movement hard to research. About 2,250 km (1,400 mi) south of the High Arctic, a wolf movement study took place in the wintertime in complete darkness, when the temperature was as low as −53 °C (−63 °F). The researchers found that wolves prey mainly on the muskoxen. There is no available information of the wolves' movements where the muskoxen were.

Diet

In the wild, Arctic wolves primarily prey on muskoxen and Arctic hares. They have also been found to prey on lemmings, caribou, Arctic foxes, birds, and beetles. It has been also found that Arctic wolves scavenge through garbage. This sort of food source will not always be found in the Arctic wolf's diet because of regional and seasonal availability. There is some debate whether the muskox or the Arctic hare is the primary prey for the hare-wolf-muskox predator-prey system. Evidence suggests that muskoxen provide long-term viability and other ungulates do not appear in the wolf's diet. Evidence suggesting that Arctic wolves depend more on hares claims that the mature wolf population paralleled the increase of hares rather than muskoxen availability. However, the degree of reliance between the two sources of food is uncertain and the amount of consumption between the two species also depends on the season and year. Debate continues when seasonal variations and the diet of young wolves is discussed. According to one study, muskox calves serve as a primary food source because the needs of pups are greater but another study suggests that "when hares were much more plentiful (Mech, 2000), wolves commonly fed them to their pups during summer." These differences may be attributed to location as well. Polar bears are rarely encountered by wolves, though there are two records of wolf packs killing polar bear cubs.

Conservation

The Arctic wolf is least concern, but it does face threats. In 1997, there was a decline in the Arctic wolf population and its prey, muskoxen (Ovibos moschatus), and Arctic hares (Lepus arcticus). This was due to unfavourable weather conditions during the summers for four years. Arctic wolf populations recovered the next summer when weather conditions returned to normal.

Additional Information

Arctic wolves have white fur year-round which allows them to blend into their snowy surroundings. Their coat is long and silky with soft, thick under fur. This is shed in the spring and the coat becomes shorter and less dense. The lengthy tail is bushy, and the legs are long giving it a lanky appearance. The feet are large and digitate with non-retractable claws. The forefeet have five toes and the hind feet have four. The skull is broad and the face and ears are well defined. Ears are slightly rounded and the face is less pointed than other species of wolf. This wolf is a subspecies of the gray wolf (Canis lupus). The year-round white coats and slightly shorter ears and noses distinguish them from the other subspecies of Canis lupus. They are also slightly smaller in stature. Male Arctic wolves generally weigh between 34 – 46 kg, and females between 36 – 38 kg.

Distribution

This sub-species lives primarily in the Arctic, the region located above 67 degrees north latitude. This is the area along the northern edge of the North American continent and northward to the North Pole, as well as along the eastern and northern shores of Greenland.

Habitat

The land in the Arctic is covered with snow and ice for most of the year except for brief periods during the summer months. Due to scarcity of grazing plants and resulting low density of prey species, wolves roam over large areas hunting for food.

Diet

They are predatory carnivores. They hunt in packs for caribou and musk-oxen. They also consume Arctic hares, ptarmigan, lemmings, and other small animals including nesting birds.

Reproduction

These wolves live in groups of seven to ten individuals. There is a highly complex social order within wolf packs and each pack has a dominant male and female, who bond for life. Mating between the pair takes place during the breeding season of January through to March. The gestation period for the pregnant alpha female is from 53 to 61 days. Permafrost in the Arctic makes it difficult for the wolves to dig dens. Instead, their dens are often rock outcroppings, caves, or shallow depressions in the tundra soil. The mother gives birth to two or three pups in late May to early June. Litter size is smaller for Arctic wolves. Pups are born blind and deaf. They have soft, fuzzy dark hair with small, droopy ears and blunt muzzles. They are entirely dependent on their mother; she is the only one who has contact with them at this time. She in turn relies on her mate to bring her food. At about ten days the pups’ eyes open and at three weeks they can hear. After a month the pups are able to eat meat. From then on the whole pack shares the job of feeding them, bringing meat which they regurgitate for the pups. Each member of the pack will affectionately lick, nuzzle, and sniff each pup. They become caregivers - providing food, play, and protection. Pups respond with squeaks and tail wags. They nibble and lick the feeder’s muzzle to stimulate regurgitation. They leave the den after eight to ten weeks to discover the outside world. As pups they are already establishing, through play, their future roles within the pack. When the pack hunts, one adult member will remain as a puppy sitter. Pups have grown strong enough to travel at six months of age, and from that time will join the other members of the pack learning survival skills. They become sexually mature at two to three years of age.

Adaptation

Wolves communicate with each other in a variety of ways. Clear communication is a key element to the success of a cooperative pack.

Body language: They have a rich vocabulary of visual signs that communicate social rank, mood, and intentions. Subtle changes in tail and ear positions, of body and head angle, making and breaking eye contact, and facial expressions are just a few. Tail movements for example are related to various feelings: friendliness, aggression, fear, status, social tension, threat, and submission are all communicated via tail position.

Vocalization: Wolves howl for many reasons, to assemble the pack before and after hunts, to locate members of the pack over distances, to warn neighboring packs of their presence, and apparently just for the fun of it. They often howl at a rendezvous site. The wolf’s howl can be heard up to 5 km away. They also growl, snarl, whine, yip, whimper, and bark.

Signs: They use scent marking to communicate their presence and territory boundaries to other wolves. This can be either urine or feces left on rocks and snow banks along their hunting trails. Wolves have a very good sense of smell. They can detect prey 1.6 km away and can sense an animal three days after it has gone.

Wolves are very social animals and live in family packs for protection and for hunting.

Pack structure: There is an alpha pair in each pack. The alpha male is the leader. Only the alpha couple breeds and with only one litter per pack. The number of pups is low in relationship to the number of adults. Wolves have concern for other wolves in the pack, with the younger members feeding and protecting the older wolves. All adults co-operate in feeding and educating the young. Wolf pack members protect each other.

Hunting: Life in a pack is extremely important to the survival of Arctic wolves. They live in very harsh conditions. Hunting together allows them to kill larger prey including musk oxen and caribou. A successful hunt depends on the cooperative efforts of the entire pack.

Wolves demonstrate intelligence in choosing prey: they look for old, sick, or weak animals that are easier to catch. Wolves work hard for their prey; they kill only one of every ten large mammals they chase. They eat all of the catch, including the bones. They have 42 teeth. Four large canine teeth are used for hanging onto and biting through flesh. Molars at the back are specialized shearing teeth referred to as carnassials. When hunting alone a wolf catches smaller animals.

Arctic wolves are well adapted to icy conditions. White fur allows them to blend into snowy surroundings. To help reduce heat loss their ears are small and rounded, the muzzle is short, and the fur is dense. Legs are shorter than other subspecies. They have tufts of hair between the pads of their feet.

Threats to Survival

Polar bears sometimes prey on Arctic wolves. Global climate change may affect these wolves. Exploration of the natural resources such as oil and gas will no doubt have an impact.