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125-456: The bowhead whale ( Balaena mysticetus ) is a species of baleen whale belonging to the family Balaenidae and is the only living representative of the genus Balaena . It is the only baleen whale endemic to the Arctic and subarctic waters, and is named after its characteristic massive triangular skull, which it uses to break through Arctic ice. Other common names of the species included

250-423: A mutation–selection balance . It is predicted that a viral quasispecies at a low but evolutionarily neutral and highly connected (that is, flat) region in the fitness landscape will outcompete a quasispecies located at a higher but narrower fitness peak in which the surrounding mutants are unfit, "the quasispecies effect" or the "survival of the flattest". There is no suggestion that a viral quasispecies resembles

375-449: A pseudogene . This is likely to have occurred about 28 million years ago and proves that dentition is an ancestral state of mysticetes. Using parsimony to study this and other ancestral characters suggests that the common ancestor of aetiocetids and edentulous mysticetes evolved lateral nutrient foramina , which are believed to have provided blood vessels and nerves a way to reach developing baleen. Further research suggests that

500-405: A ring species . Also, among organisms that reproduce only asexually , the concept of a reproductive species breaks down, and each clone is potentially a microspecies. Although none of these are entirely satisfactory definitions, and while the concept of species may not be a perfect model of life, it is still a useful tool to scientists and conservationists for studying life on Earth, regardless of

625-633: A subsistence level, with low annual bowhead total quotas set by the International Whaling Commission in conjunction with individual village limits set by the Alaska Eskimo Whaling Commission. Bowhead hunting is limited to whaling crews who are: Species A species ( pl. : species) is a population of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring , typically by sexual reproduction . It

750-400: A "classical" method of determining species, such as with Linnaeus, early in evolutionary theory. However, different phenotypes are not necessarily different species (e.g. a four-winged Drosophila born to a two-winged mother is not a different species). Species named in this manner are called morphospecies . In the 1970s, Robert R. Sokal , Theodore J. Crovello and Peter Sneath proposed

875-424: A 'smallest clade' idea" (a phylogenetic species concept). Mishler and Wilkins and others concur with this approach, even though this would raise difficulties in biological nomenclature. Wilkins cited the ichthyologist Charles Tate Regan 's early 20th century remark that "a species is whatever a suitably qualified biologist chooses to call a species". Wilkins noted that the philosopher Philip Kitcher called this

1000-403: A South American deposit dating back 23 million years. An unknown species of right whale, the so-called "Swedenborg whale", which was proposed by Emanuel Swedenborg in the 18th century, was once thought to be a North Atlantic right whale. Based on later DNA analysis, those fossil bones claimed to be from Swedenborg whales were confirmed to be from bowhead whales. The bowhead whale has

1125-453: A change in skull structure and throat elasticity . It would be highly unlikely for all of these changes to occur at once. Therefore, it is proposed that Oligocene aetiocetids possess both ancestral and descendant character states regarding feeding strategies. This makes them mosaic taxa , showing that either baleen evolved before dentition was lost or that the traits for filter feeding originally evolved for other functions. It also shows that

1250-428: A connected series of neighbouring populations, each of which can sexually interbreed with adjacent related populations, but for which there exist at least two "end" populations in the series, which are too distantly related to interbreed, though there is a potential gene flow between each "linked" population. Such non-breeding, though genetically connected, "end" populations may co-exist in the same region thus closing

1375-432: A different species from its ancestors. Viruses have enormous populations, are doubtfully living since they consist of little more than a string of DNA or RNA in a protein coat, and mutate rapidly. All of these factors make conventional species concepts largely inapplicable. A viral quasispecies is a group of genotypes related by similar mutations, competing within a highly mutagenic environment, and hence governed by

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1500-508: A genetic boundary suitable for defining a species concept is present. DNA barcoding has been proposed as a way to distinguish species suitable even for non-specialists to use. One of the barcodes is a region of mitochondrial DNA within the gene for cytochrome c oxidase . A database, Barcode of Life Data System , contains DNA barcode sequences from over 190,000 species. However, scientists such as Rob DeSalle have expressed concern that classical taxonomy and DNA barcoding, which they consider

1625-422: A large, robust, dark-coloured body and a white chin. It has a massive triangular skull , which it uses to break through the Arctic ice to breathe. Inuit hunters have reported bowheads surfacing through 60 cm (24 in) of ice. It also possesses a strongly bowed lower jaw and a narrow upper jaw. Its baleen is the longest of that of any whale, at 3 m (9.8 ft), and is used to strain tiny prey from

1750-1027: A large, upturning lip on the lower jaw that helps to reinforce and hold the baleen plates within the mouth. This also prevents buckling or breakage of the plates from the pressure of the water passing through them as the whale advances. To feed, water is filtered through the fine hairs of keratin of the baleen plates, trapping the prey inside near the tongue where it is then swallowed. The diet consists of mostly zooplankton , which includes krill , copepods , mysids , amphipods , and many other crustaceans . About 1.8 t (2 short tons) of food are consumed each day. While foraging, bowheads are solitary or occur in groups of two to 10 or more. Bowhead whales are highly vocal and use low frequency (<1000 Hz) sounds to communicate while travelling, feeding, and socialising. Intense calls for communication and navigation are produced especially during migration season. During breeding season, bowheads make long, complex, variable songs for mating calls. Many tens of distinct songs are sung by

1875-492: A misnomer, need to be reconciled, as they delimit species differently. Genetic introgression mediated by endosymbionts and other vectors can further make barcodes ineffective in the identification of species. A phylogenetic or cladistic species is "the smallest aggregation of populations (sexual) or lineages (asexual) diagnosable by a unique combination of character states in comparable individuals (semaphoronts)". The empirical basis – observed character states – provides

2000-449: A particular species, including which genus (and higher taxa) it is placed in, is a hypothesis about the evolutionary relationships and distinguishability of that group of organisms. As further information comes to hand, the hypothesis may be corroborated or refuted. Sometimes, especially in the past when communication was more difficult, taxonomists working in isolation have given two distinct names to individual organisms later identified as

2125-476: A population in a single season. From 2010 through to 2014, near Greenland , 184 distinct songs were recorded from a population of around 300 animals. Sexual activity occurs between pairs and in boisterous groups of several males and one or two females. Breeding season is observed from March through August; conception is believed to occur primarily in March when song activity is at its highest. Reproduction can begin when

2250-400: A short way of saying that something applies to many species within a genus, but not to all. If scientists mean that something applies to all species within a genus, they use the genus name without the specific name or epithet. The names of genera and species are usually printed in italics . However, abbreviations such as "sp." should not be italicised. When a species' identity is not clear,

2375-402: A single dive is usually limited to 9–18 minutes. The bowhead is not thought to be a deep diver, but can reach a depth down to 150 m (500 ft). It is a slow swimmer, normally travelling around 2–5 km/h (0.56–1.39 m/s; 1.2–3.1 mph). When fleeing from danger, it can travel at a speed of 10 km/h (2.8 m/s; 6.2 mph). During periods of feeding, the average swim speed

2500-409: A single genus or two. As recently as 1998, Dale Rice listed just two species – B. glacialis (the right whales) and B. mysticetus (the bowheads) – in his comprehensive and otherwise authoritative classification. Studies in the 2000s finally provided clear evidence that the three living right whale species comprise a phylogenetic lineage, distinct from the bowhead, and that the bowhead and

2625-404: A specialist may use "cf." before the epithet to indicate that confirmation is required. The abbreviations "nr." (near) or "aff." (affine) may be used when the identity is unclear but when the species appears to be similar to the species mentioned after. With the rise of online databases, codes have been devised to provide identifiers for species that are already defined, including: The naming of

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2750-523: A species as groups of actually or potentially interbreeding natural populations, which are reproductively isolated from other such groups. It has been argued that this definition is a natural consequence of the effect of sexual reproduction on the dynamics of natural selection. Mayr's use of the adjective "potentially" has been a point of debate; some interpretations exclude unusual or artificial matings that occur only in captivity, or that involve animals capable of mating but that do not normally do so in

2875-400: A species as determined by a taxonomist. A typological species is a group of organisms in which individuals conform to certain fixed properties (a type), so that even pre-literate people often recognise the same taxon as do modern taxonomists. The clusters of variations or phenotypes within specimens (such as longer or shorter tails) would differentiate the species. This method was used as

3000-488: A species. All species definitions assume that an organism acquires its genes from one or two parents very like the "daughter" organism, but that is not what happens in HGT. There is strong evidence of HGT between very dissimilar groups of prokaryotes , and at least occasionally between dissimilar groups of eukaryotes , including some crustaceans and echinoderms . The evolutionary biologist James Mallet concludes that there

3125-685: A species. Generally the term includes the unknown element of a distinct act of creation. Many authors have argued that a simple textbook definition, following Mayr's concept, works well for most multi-celled organisms , but breaks down in several situations: Species identification is made difficult by discordance between molecular and morphological investigations; these can be categorised as two types: (i) one morphology, multiple lineages (e.g. morphological convergence , cryptic species ) and (ii) one lineage, multiple morphologies (e.g. phenotypic plasticity , multiple life-cycle stages). In addition, horizontal gene transfer (HGT) makes it difficult to define

3250-519: A taxonomic decision at the discretion of cognizant specialists, is not governed by the Codes of Zoological or Botanical Nomenclature, in contrast to the PhyloCode , and contrary to what is done in several other fields, in which the definitions of technical terms, like geochronological units and geopolitical entities, are explicitly delimited. The nomenclatural codes that guide the naming of species, including

3375-506: A traditional biological species. The International Committee on Taxonomy of Viruses has since 1962 developed a universal taxonomic scheme for viruses; this has stabilised viral taxonomy. Most modern textbooks make use of Ernst Mayr 's 1942 definition, known as the Biological Species Concept as a basis for further discussion on the definition of species. It is also called a reproductive or isolation concept. This defines

3500-413: A tubular structure with a hollow medulla (inner core) enclosed by a tubular layer with a diameter varying from 60 to 900 microns, which had approximately 2.7 times higher calcium content than the outer solid shell. The elastic modulus in the longitudinal direction and the transverse direction are 270 megapascals ( MPa ) and 200 MPa, respectively. This difference in the elastic moduli could be attributed to

3625-447: A variation on the morphological species concept, a phenetic species, defined as a set of organisms with a similar phenotype to each other, but a different phenotype from other sets of organisms. It differs from the morphological species concept in including a numerical measure of distance or similarity to cluster entities based on multivariate comparisons of a reasonably large number of phenotypic traits. A mate-recognition species

3750-515: A variety of reasons. Viruses are a special case, driven by a balance of mutation and selection , and can be treated as quasispecies . Biologists and taxonomists have made many attempts to define species, beginning from morphology and moving towards genetics . Early taxonomists such as Linnaeus had no option but to describe what they saw: this was later formalised as the typological or morphological species concept. Ernst Mayr emphasised reproductive isolation, but this, like other species concepts,

3875-457: A well-defined area of 3,700 km (1,100  sq nmi ) north of Igloolik Island to Fury and Hecla Strait and Kapuiviit and Gifford Fiord , and into Gulf of Boothia and Prince Regent Inlet . Northward migrating along western Foxe Basin to eastern side of the basin also occurs in spring. Not much is known about the endangered Sea of Okhotsk population. To learn more about the population, these mammals have been regularly observed near

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4000-503: A whale is 10 to 15 years old. The gestation period is 13–14 months with females producing a calf once every three to four years. Lactation typically lasts about a year. To survive in the cold water immediately after birth, calves are born with a thick layer of blubber . Within 30 minutes of birth, bowhead calves are able to swim on their own. A newborn calf is typically 4–4.5 m (13–15 ft) long, weighs roughly 1,000 kg (2,200 lb), and grows to 8.2 m (27 ft) within

4125-438: Is "an entity composed of organisms which maintains its identity from other such entities through time and over space, and which has its own independent evolutionary fate and historical tendencies". This differs from the biological species concept in embodying persistence over time. Wiley and Mayden stated that they see the evolutionary species concept as "identical" to Willi Hennig 's species-as-lineages concept, and asserted that

4250-446: Is 268 years based on genetic analysis. A greater number of cells present in an organism was once believed to result in greater chances of mutations that cause age-related diseases and cancer . Although the bowhead whale has thousands of times more cells than other mammals, it has a much higher resistance to cancer and aging. In 2015, scientists from the US and UK were able to successfully map

4375-400: Is a group of sexually reproducing organisms that recognise one another as potential mates. Expanding on this to allow for post-mating isolation, a cohesion species is the most inclusive population of individuals having the potential for phenotypic cohesion through intrinsic cohesion mechanisms; no matter whether populations can hybridise successfully, they are still distinct cohesion species if

4500-458: Is a set of organisms adapted to a particular set of resources, called a niche, in the environment. According to this concept, populations form the discrete phenetic clusters that we recognise as species because the ecological and evolutionary processes controlling how resources are divided up tend to produce those clusters. A genetic species as defined by Robert Baker and Robert Bradley is a set of genetically isolated interbreeding populations. This

4625-502: Is an important habitat for whales that were observed to be relatively active and to interact with humans positively, or to rest on sea floors. These whales belong to Davis Strait stock. Isabella Bay in Niginganiq National Wildlife Area is the first wildlife sanctuary in the world to be designed specially for bowhead whales. However, moultings have not been recorded in this area due to environmental factors. In 1978

4750-473: Is believed to have occurred during Early Oligocene when Antarctica broke off from Gondwana and the Antarctic Circumpolar Current was formed, increasing productivity of ocean environments. This occurred because the current kept warm ocean waters away from the area that is now Antarctica, producing steep gradients in temperature, salinity , light, and nutrients, where the warm water meets

4875-414: Is between 8 and 8.7 million. About 14% of these had been described by 2011. All species (except viruses ) are given a two-part name , called a "binomial". The first part of a binomial is the genus to which the species belongs. The second part is called the specific name or the specific epithet (in botanical nomenclature , also sometimes in zoological nomenclature ). For example, Boa constrictor

5000-414: Is called speciation . Charles Darwin was the first to describe the role of natural selection in speciation in his 1859 book The Origin of Species . Speciation depends on a measure of reproductive isolation , a reduced gene flow. This occurs most easily in allopatric speciation, where populations are separated geographically and can diverge gradually as mutations accumulate. Reproductive isolation

5125-403: Is described formally, in a publication that assigns it a unique scientific name. The description typically provides means for identifying the new species, which may not be based solely on morphology (see cryptic species ), differentiating it from other previously described and related or confusable species and provides a validly published name (in botany) or an available name (in zoology) when

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5250-671: Is further weakened by the existence of microspecies , groups of organisms, including many plants, with very little genetic variability, usually forming species aggregates . For example, the dandelion Taraxacum officinale and the blackberry Rubus fruticosus are aggregates with many microspecies—perhaps 400 in the case of the blackberry and over 200 in the dandelion, complicated by hybridisation , apomixis and polyploidy , making gene flow between populations difficult to determine, and their taxonomy debatable. Species complexes occur in insects such as Heliconius butterflies, vertebrates such as Hypsiboas treefrogs, and fungi such as

5375-726: Is hard or even impossible to test. Later biologists have tried to refine Mayr's definition with the recognition and cohesion concepts, among others. Many of the concepts are quite similar or overlap, so they are not easy to count: the biologist R. L. Mayden recorded about 24 concepts, and the philosopher of science John Wilkins counted 26. Wilkins further grouped the species concepts into seven basic kinds of concepts: (1) agamospecies for asexual organisms (2) biospecies for reproductively isolated sexual organisms (3) ecospecies based on ecological niches (4) evolutionary species based on lineage (5) genetic species based on gene pool (6) morphospecies based on form or phenotype and (7) taxonomic species,

5500-403: Is increased to 1.1–2.5 m/s (4.0–9.0 km/h; 2.5–5.6 mph). The head of the bowhead whale comprises a third of its body length, creating an enormous feeding apparatus. The bowhead whale is a filter feeder , and feeds by swimming forward with its mouth wide open. It has hundreds of overlapping baleen plates consisting of keratin hanging from each side of the upper jaw. The mouth has

5625-460: Is indicated by baleen-related skull modifications being found in fossils from considerably earlier, including a buttress of bone in the upper jaw beneath the eyes, and loose lower jaw bones at the chin. Baleen is believed to have evolved around 30 million years ago, possibly from a hard, gummy upper jaw, like the one a Dall's porpoise has; it closely resembles baleen at the microscopic level. The initial evolution and radiation of baleen plates

5750-524: Is less well known. About 1,200 were off West Greenland in 2006, while the Svalbard population may only number in the tens. However, the numbers have been increasing in recent years. The Hudson Bay – Foxe Basin population is distinct from the Baffin Bay  –  Davis Strait group. The original population size of this local group is unclear, but possibly about 500 to 600 whales annually summered in

5875-471: Is mostly restricted to the northwestern part along with Wager Bay , Repulse Bay , Southampton Island (one of two main known summering areas), Frozen Strait , northern Foxe Basin, and north of Igloolik in summer. Satellite tracking indicates that some portions of the group within the bay do not venture further south than Whale Cove and areas south of Coats and Mansel Islands . Cow – calf pairs and juveniles up to 13.5 m (44 ft) in length make up

6000-403: Is no easy way to tell whether related geographic or temporal forms belong to the same or different species. Species gaps can be verified only locally and at a point of time. One is forced to admit that Darwin's insight is correct: any local reality or integrity of species is greatly reduced over large geographic ranges and time periods. The botanist Brent Mishler argued that the species concept

6125-468: Is not valid, notably because gene flux decreases gradually rather than in discrete steps, which hampers objective delimitation of species. Indeed, complex and unstable patterns of gene flux have been observed in cichlid teleosts of the East African Great Lakes . Wilkins argued that "if we were being true to evolution and the consequent phylogenetic approach to taxa, we should replace it with

6250-400: Is one of the species of the genus Boa , with constrictor being the species' epithet. While the definitions given above may seem adequate at first glance, when looked at more closely they represent problematic species concepts. For example, the boundaries between closely related species become unclear with hybridisation , in a species complex of hundreds of similar microspecies , and in

6375-566: Is possibly functioning as the most important habitat for this population. It is unclear whether this population is a remnant of the historic Svalbard group, recolonized individuals from other stocks, or if a mixing of these two or more stocks has taken place. In 2015, discoveries of the refuge along eastern Greenland where whaling ships could not reach due to ice floes and largest numbers of whales (80–100 individuals) ever sighted between Spitsbergen and Greenland indicate that more whales than previously considered survived whaling periods, and flows from

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6500-586: Is similar to Mayr's Biological Species Concept, but stresses genetic rather than reproductive isolation. In the 21st century, a genetic species could be established by comparing DNA sequences. Earlier, other methods were available, such as comparing karyotypes (sets of chromosomes ) and allozymes ( enzyme variants). An evolutionarily significant unit (ESU) or "wildlife species" is a population of organisms considered distinct for purposes of conservation. In palaeontology , with only comparative anatomy (morphology) and histology from fossils as evidence,

6625-740: Is sometimes an important source of genetic variation. Viruses can transfer genes between species. Bacteria can exchange plasmids with bacteria of other species, including some apparently distantly related ones in different phylogenetic domains , making analysis of their relationships difficult, and weakening the concept of a bacterial species. Baleen Depending on the species, a baleen plate can be 0.5 to 3.5 m (1.6 to 11.5 ft) long, and weigh up to 90 kg (200 lb). Its hairy fringes are called baleen hair or whalebone hair. They are also called baleen bristles, which in sei whales are highly calcified, with calcification functioning to increase their stiffness. Baleen plates are broader at

6750-434: Is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity . Other ways of defining species include their karyotype , DNA sequence, morphology , behaviour, or ecological niche . In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes

6875-594: Is threatened by hybridisation, but this can be selected against once a pair of populations have incompatible alleles of the same gene, as described in the Bateson–Dobzhansky–Muller model . A different mechanism, phyletic speciation, involves one lineage gradually changing over time into a new and distinct form (a chronospecies ), without increasing the number of resultant species. Horizontal gene transfer between organisms of different species, either through hybridisation , antigenic shift , or reassortment ,

7000-400: Is true that many early baleen whales also had teeth, these were probably used only peripherally, or perhaps not at all (again like Dall's porpoise, which catches squid and fish by gripping them against its hard upper jaw). Intense research has been carried out to sort out the evolution and phylogenetic history of mysticetes, but much debate surrounds this issue. A whale's baleen plates play

7125-770: The Davis Strait , and by the first quarter of the 19th century, Baffin Bay . In the North Pacific, the first bowheads were taken off the eastern coast of Kamchatka by the Danish whaleship Neptun , Captain Thomas Sodring, in 1845. In 1847, the first bowheads were caught in the Sea of Okhotsk, and the following year, Captain Thomas Welcome Roys , in the bark Superior , of Sag Harbor , caught

7250-465: The Greenland right whale , Arctic whale , steeple-top , and polar whale . Bowheads have the largest mouth of any animal representing almost one-third of the length of the body, the longest baleen plates with a maximum length of 4 m (13 ft), and may be the longest-lived mammals, with the ability to reach an age of more than 200 years. The bowhead was an early whaling target. Their population

7375-523: The ICZN for animals and the ICN for plants, do not make rules for defining the boundaries of the species. Research can change the boundaries, also known as circumscription, based on new evidence. Species may then need to be distinguished by the boundary definitions used, and in such cases the names may be qualified with sensu stricto ("in the narrow sense") to denote usage in the exact meaning given by an author such as

7500-521: The International Whaling Commission (IWC) introduced a hunting strike quota for the Bering - Chukchi - Beaufort Sea (BCB) bowhead. The quota has remained at 67 strikes per year since 1998 and represents about 0.5 percent of BCB population. The population of bowheads in West Greenland and Canada is estimated to be 6,000 and rising, and hunts in this are minimal (<0.001 percent). Both stocks are rising, and

7625-480: The Shantar Islands , very close to the shore, such as at Ongachan Bay . Several companies provide whale-watching services, which are mostly land-based. According to Russian scientists, this total population likely does not exceed 400 animals. Scientific research on this population was seldom done before 2009, when researchers studying belugas noticed concentrations of bowheads in the study area. Thus, bowheads in

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7750-559: The White Sea region, where few or no animals currently migrate, such as the Kola and Kanin Peninsula . Today, the number of sightings elsewhere is very small, but with increasing regularities with whales having strong regional connections. Whales have also started approaching townships and inhabited areas such as around Longyearbyen . The waters around the marine mammal sanctuary of Franz Josef Land

7875-399: The fly agaric . Natural hybridisation presents a challenge to the concept of a reproductively isolated species, as fertile hybrids permit gene flow between two populations. For example, the carrion crow Corvus corone and the hooded crow Corvus cornix appear and are classified as separate species, yet they can hybridise where their geographical ranges overlap. A ring species is

8000-498: The jaguar ( Panthera onca ) of Latin America or the leopard ( Panthera pardus ) of Africa and Asia. In contrast, the scientific names of species are chosen to be unique and universal (except for some inter-code homonyms ); they are in two parts used together : the genus as in Puma , and the specific epithet as in concolor . A species is given a taxonomic name when a type specimen

8125-406: The "cynical species concept", and arguing that far from being cynical, it usefully leads to an empirical taxonomy for any given group, based on taxonomists' experience. Other biologists have gone further and argued that we should abandon species entirely, and refer to the "Least Inclusive Taxonomic Units" (LITUs), a view that would be coherent with current evolutionary theory. The species concept

8250-531: The Basques killed them as they migrated south through the Strait of Belle Isle in the fall and early winter. In 1611, the first whaling expedition sailed to Spitsbergen . The whaling settlement Smeerenburg was founded on Spitsbergen in 1619. By midcentury, the population(s) there had practically been wiped out, forcing whalers to voyage into the "West Ice"—the pack ice off Greenland 's east coast. By 1719, they had reached

8375-668: The Pleistocene were far more southerly as fossils have been excavated from Italy and North Carolina , thus could have overlapped between those of Eubalaena based on those locations. Generally, five stocks of bowhead whales are recognized: 1) the Western Arctic stock in the Bering, Chukchi, and Beaufort Seas, 2) the Hudson Bay and Foxe Basin stock, 3) the Baffin Bay and Davis Strait stock, 4)

8500-553: The Sea of Okhotsk stock, and 5) the Svalbard-Barents Sea stock. However, recent evidence suggests that the Hudson Bay and Foxe Basin stock and the Baffin Bay and Davis Strait stock should be considered one stock based on genetics and movements of tagged whales. The Western Arctic bowhead population, also known as the Bering-Chukchi-Beaufort population, has recovered since the commercial harvest of this stock ceased in

8625-625: The Sea of Okhotsk were once called "forgotten whales" by researchers. The WWF welcomed the creation of a nature sanctuary in the region Possibly, vagrants from this population occasionally reach into Asian nations such as off Japan or the Korean Peninsula (although this record might be of a right whale). The first documented report of the species in Japanese waters was of a strayed infant (7 m (23 ft)) caught in Osaka Bay on 23 June 1969, and

8750-405: The abbreviation "sp." in the singular or "spp." (standing for species pluralis , Latin for "multiple species") in the plural in place of the specific name or epithet (e.g. Canis sp.). This commonly occurs when authors are confident that some individuals belong to a particular genus but are not sure to which exact species they belong, as is common in paleontology . Authors may also use "spp." as

8875-570: The amount of hybridisation is insufficient to completely mix their respective gene pools . A further development of the recognition concept is provided by the biosemiotic concept of species. In microbiology , genes can move freely even between distantly related bacteria, possibly extending to the whole bacterial domain. As a rule of thumb, microbiologists have assumed that members of Bacteria or Archaea with 16S ribosomal RNA gene sequences more similar than 97% to each other need to be checked by DNA–DNA hybridisation to decide if they belong to

9000-468: The baleen of Aetiocetus was arranged in bundles between widely spaced teeth. If true, this combination of baleen and dentition in Aetiocetus would act as a transition state between odontocetes and mysticetes. This intermediate step is further supported by evidence of other changes that occurred with the evolution of baleen that make it possible for the organisms to survive using filter feeding, such as

9125-429: The baleen, thus sieving out the prey, which it then swallows. Whale baleen is the mostly mineralized keratin-based bio-material consisting of parallel plates suspended down the mouth of the whale. Baleen's mechanical properties of being strong and flexible made it a popular material for numerous applications requiring such a property (see Human uses section). The basic structure of the whale baleen has been described as

9250-474: The biological species concept, "the several versions" of the phylogenetic species concept, and the idea that species are of the same kind as higher taxa are not suitable for biodiversity studies (with the intention of estimating the number of species accurately). They further suggested that the concept works for both asexual and sexually-reproducing species. A version of the concept is Kevin de Queiroz 's "General Lineage Concept of Species". An ecological species

9375-505: The biological species concept, a cladistic species does not rely on reproductive isolation – its criteria are independent of processes that are integral in other concepts. Therefore, it applies to asexual lineages. However, it does not always provide clear cut and intuitively satisfying boundaries between taxa, and may require multiple sources of evidence, such as more than one polymorphic locus, to give plausible results. An evolutionary species, suggested by George Gaylord Simpson in 1951,

9500-470: The bowhead subsistence harvest with the National Oceanic and Atmospheric Administration. The Alaskan villages that participate in the bowhead subsistence harvest include Barrow, Point Hope, Point Lay, Wainwright, Nuiqsut, Kaktovik, Gambell, Savoonga, Kivalina, Wales, and Little Diomede. The annual subsistence harvest of the Western Arctic stock has ranged from 14 to 72, amounting to an estimated 0.1-0.5% of

9625-541: The bowhead whale has a vestigial pelvis that is not connected to the spine. Bowhead whales are comparable in size to the three species of right whales . According to whaling captain William Scoresby Jr., the longest bowhead he measured was 17.7 m (58 ft) long, while the longest measurement he had ever heard of was of a 20.4 m (67 ft) whale caught at Godhavn , Greenland, in early 1813. He also spoke of one, caught near Spitsbergen around 1800, that

9750-433: The cold. The transition from teeth to baleen is proposed to have occurred stepwise , from teeth to a hybrid to baleen. It is known that modern mysticetes have teeth initially and then develop baleen plate germs in utero , but lose their dentition and have only baleen during their juvenile years and adulthood. However, developing mysticetes do not produce tooth enamel because at some point this trait evolved to become

9875-729: The compressive response. Crack formation is also different for both the transverse and longitudinal orientation. For the transverse direction, cracks are redirected along the tubules, which enhances the baleen's resistance to fracture and once the crack enters the tubule it is then directed along the weaker interface rather than penetrating through either the tubule or lamellae. People formerly used baleen (usually referred to as "whalebone") for making numerous items where flexibility and strength were required, including baskets , backscratchers , collar stiffeners , buggy whips , parasol ribs, switches, crinoline petticoats, farthingales , busks , and corset stays , but also pieces of armour. It

10000-433: The concept of a chronospecies can be applied. During anagenesis (evolution, not necessarily involving branching), some palaeontologists seek to identify a sequence of species, each one derived from the phyletically extinct one before through continuous, slow and more or less uniform change. In such a time sequence, some palaeontologists assess how much change is required for a morphologically distinct form to be considered

10125-419: The corpus cavernosum maxillaris, extends along the centre of the hard plate, forming two large lobes at the rostral palate. The tissue is histologically similar to that of the corpus cavernosum of the mammalian penis . This organ is thought to provide a mechanism of cooling for the whale (which is normally protected from the cold Arctic waters by 40 cm (16 in) or more of fat). During physical exertion,

10250-695: The early 1900s. A 2019 study estimated that the Western Arctic population was 12,505; although it was lower than the 2011 value of 16,820, the surveyors believed there was no significant decline in 2011–2019 due to the unusual conditions of whale migration and observation in 2019. The yearly growth rate of the Western Arctic bowhead population was 3.7% from 1978 to 2011. These data suggest that the Western Arctic bowhead stock may be near its precommercial whaling level. Migration patterns of this population are being affected by climate change . Alaskan Natives continue to hunt small numbers of bowhead whales for subsistence purposes. The Alaska Eskimo Whaling Commission co-manages

10375-435: The evidence to support hypotheses about evolutionarily divergent lineages that have maintained their hereditary integrity through time and space. Molecular markers may be used to determine diagnostic genetic differences in the nuclear or mitochondrial DNA of various species. For example, in a study done on fungi , studying the nucleotide characters using cladistic species produced the most accurate results in recognising

10500-426: The evolution could have occurred gradually because the ancestral state was originally maintained. Therefore, the mosaic whales could have exploited new resources using filter feeding while not abandoning their previous prey strategies. The result of this stepwise transition is apparent in modern-day baleen whales, because of their enamel pseudogenes and their in utero development and reabsorbing of teeth. If it

10625-538: The first bowheads in the Bering Strait region. By 1849, 50 ships were hunting bowheads in each area; in the Bering Strait, 500 whales were killed that year, and that number jumped to more than 2000 in 1850. By 1852, 220 ships were cruising around the Bering Strait region, which killed over 2,600 whales. Between 1854 and 1857, the fleet shifted to the Sea of Okhotsk, where 100–160 ships cruised annually. During 1858–1860,

10750-640: The first live sighting was of a 10 m (33 ft) juvenile around Shiretoko Peninsula (the southernmost of ice floe range in the Northern Hemisphere) on 21 to 23 June 2015. Fossils have been excavated on Hokkaido , but it is unclear whether the northern coasts of Japan were once included in seasonal or occasional migration ranges. Genetic studies suggest Okhotsk population share common ancestry with whales in Bering-Chukchi-Beaufort Seas, and repeated mixings had occurred between whales in

10875-450: The first year. Bowhead whales are considered to be the longest-living mammals , living for over 200 years. In May 2007, a 15 m (49 ft) specimen caught off the Alaskan coast was discovered with the 89 mm (3.5 in) head of an explosive bomb lance of a model manufactured between 1879 and 1885, so the whale was probably bomb lanced sometime between those years, and its age at

11000-414: The forming/melting of ice. Historically, bowhead whales' range may have been broader and more southerly than currently thought. Bowheads were abundant around Labrador, Newfoundland ( Strait of Belle Isle ) and the northern Gulf of St Lawrence until at least the 16th and 17th centuries. It is unclear whether this was due to the colder climate during these periods. The distribution of Balaena spp. during

11125-580: The gene UCP1 , a gene involved in thermoregulation , can explain differences in the metabolic rates in cells. The bowhead whale is the only baleen whale to spend its entire life in the Arctic and subarctic waters. The Alaskan population spends the winter months in the southwestern Bering Sea . The group migrates northward in the spring, following openings in the ice, into the Chukchi and Beaufort seas. The whale's range varies depending on climate changes and on

11250-583: The gumline (base). The plates have been compared to sieves or Venetian blinds . As a material for various human uses, baleen is usually called whalebone , which is a misnomer . The word " baleen " derives from the Latin bālaena , related to the Greek phalaina – both of which mean "whale". The oldest true fossils of baleen are only 15 million years old because baleen rarely fossilizes, but scientists believe it originated considerably earlier than that. This

11375-607: The indigenous hunts seem to be self-sustaining. Orca are also known predators. There is no consensus on the number of deaths by orca. Bowheads seek the ice and shallow waters' safety when threatened by orca. The Inuit have a traditional word for this behavior to give historical context that this is not a new phenomenon. Global warming is increasing the frequency that orca are observed in the far north. A once-rare event, orca are now seen more frequently. There are no reports of attacks on bowheads by sharks. The bowhead whale has been hunted for blubber , meat, oil , bones, and baleen. Like

11500-537: The majority of summering aggregation in the northern Foxe Basin, while matured males and noncalving females may use the northwestern part of Hudson Bay. Fewer whales also migrate to the west coast of Hudson Bay and Mansel and Ottawa Islands . Bowhead ranges within Hudson Bay are usually considered not to cover southern parts, but at least some whales migrate to locations further south such as Sanikiluaq and Churchill river mouth . Congregation within Foxe Basin occurs in

11625-402: The most important role in its filter-feeding process. To feed, a baleen whale opens its mouth widely and scoops in dense shoals of prey (such as krill , copepods , small fish , and sometimes birds that happen to be near the shoals), together with large volumes of water. It then partly shuts its mouth and presses its tongue against its upper jaw, forcing the water to pass out sideways through

11750-428: The next 180 years, the family Balaenidae was the subject of great taxonometric debate. Authorities have repeatedly recategorized the three populations of right whale plus the bowhead whale, as one, two, three or four species, either in a single genus or in two separate genera. Eventually, it was recognized that bowheads and right whales were different, but there was still no strong consensus as to whether they shared

11875-589: The northwestern part of the bay in the 1860s. It is likely that the number of whales that actually inhabit Hudson Bay is much smaller than the total population size of this group, but reports from local indigenous people indicate that this population is increasing over decades. Larger portions of the bay are used for summering, while wintering is on a smaller scale. Some animals winter in Hudson Strait , most notably north of Igloolik Island and north eastern Hudson Bay. Distribution patterns in these regions are affected by

12000-478: The numerous fungi species of all the concepts studied. Versions of the phylogenetic species concept that emphasise monophyly or diagnosability may lead to splitting of existing species, for example in Bovidae , by recognising old subspecies as species, despite the fact that there are no reproductive barriers, and populations may intergrade morphologically. Others have called this approach taxonomic inflation , diluting

12125-456: The one claimed in 1850) may weigh up to 100 t (110 short tons; 98 long tons). Analysis of hundreds of DNA samples from living whales and from baleen used in vessels, toys, and housing material has shown that Arctic bowhead whales have lost a significant portion of their genetic diversity in the past 500 years. Bowheads originally crossed ice-covered inlets and straits to exchange genes between Atlantic and Pacific populations. This conclusion

12250-421: The other populations are possible. During expeditions by a tour operator 'Arctic Kingdom', a large group of bowheads seemingly involved in courtship activities was discovered in very shallow bays south of Qikiqtarjuaq in 2012. Floating skins and rubbing behaviours at sea bottom indicated possible moulting had taken place. Moulting behaviours had never or seldom been documented for this species before. This area

12375-615: The pack ice in the northeastern Sea of Okhotsk, then in Tausk Bay and Northeast Gulf ( Shelikhov Gulf ). Soon, ships expanded to the west, catching them around Iony Island and then around the Shantar Islands . In the Western Arctic, they mainly caught them in the Anadyr Gulf , the Bering Strait, and around St. Lawrence Island . They later spread to the western Beaufort Sea (1854) and the Mackenzie River delta (1889). Commercial whaling,

12500-585: The paper is accepted for publication. The type material is usually held in a permanent repository, often the research collection of a major museum or university, that allows independent verification and the means to compare specimens. Describers of new species are asked to choose names that, in the words of the International Code of Zoological Nomenclature , are "appropriate, compact, euphonious, memorable, and do not cause offence". Books and articles sometimes intentionally do not identify species fully, using

12625-674: The person who named the species, while the antonym sensu lato ("in the broad sense") denotes a wider usage, for instance including other subspecies. Other abbreviations such as "auct." ("author"), and qualifiers such as "non" ("not") may be used to further clarify the sense in which the specified authors delineated or described the species. Species are subject to change, whether by evolving into new species, exchanging genes with other species, merging with other species or by becoming extinct. The evolutionary process by which biological populations of sexually-reproducing organisms evolve to become distinct or reproductively isolated as species

12750-466: The population. In March 2008, Canada's Department of Fisheries and Oceans stated the previous estimates in the eastern Arctic had undercounted, with a new estimate of 14,400 animals (range 4,800–43,000). These larger numbers correspond to prewhaling estimates, indicating the population has fully recovered. However, if climate change substantially shrinks sea ice, these whales could be threatened by increased shipping traffic. The status of other populations

12875-530: The presence of orca , and bowheads can disappear from normal ranges in the presence of atypical numbers of orca. Increased mortality caused by orca attack is a possible outcome of climate change , as reduced ice coverage is expected to result in fewer areas that the bowheads can use for shelter from attack. Whaling grounds in the 19th century stretched from Marble Island to Roes Welcome Sound and to Lyon Inlet and Fisher Strait , and whales still migrate through most of these areas. Distribution within Hudson Bay

13000-534: The principal cause of the population decline, is over. Bowhead whales are now hunted on a subsistence level by native peoples of North America . In 2024, the Inuit hunters of Aklavik , Northwest Territories were permitted to hunt and kill one bowhead whale with the whale meat , an important part of Inuit cuisine , to be distributed to Inuvialuit and Gwich'in communities in the region. Some Alaska Natives continue by tradition to hunt bowhead and beluga whales on

13125-487: The result of misclassification leading to questions on whether there really are any ring species. The commonly used names for kinds of organisms are often ambiguous: "cat" could mean the domestic cat, Felis catus , or the cat family, Felidae . Another problem with common names is that they often vary from place to place, so that puma, cougar, catamount, panther, painter and mountain lion all mean Puma concolor in various parts of America, while "panther" may also mean

13250-453: The right whale, it swims slowly, and floats after death, making it ideal for whaling. Before commercial whaling, they were estimated to number 50,000. Paleo-Eskimo sites indicate bowhead whales were eaten in sites from perhaps 4000 BC. Inuit people near the Pacific developed specific hunting tools, with the whales providing food and fuel. Commercial bowhead whaling began in the 16th century when

13375-508: The right whales are rightly classified into two separate genera. The right whales were thus confirmed to be in a separate genus, Eubalaena . The relationship is shown in the cladogram below:   E. glacialis   (North Atlantic right whale)   E. japonica   (North Pacific right whale)   E. australis   (Southern right whale)   B. mysticetus   (bowhead whale) The earlier fossil record shows no related cetacean after Morenocetus , found in

13500-573: The ring. Ring species thus present a difficulty for any species concept that relies on reproductive isolation. However, ring species are at best rare. Proposed examples include the herring gull – lesser black-backed gull complex around the North pole, the Ensatina eschscholtzii group of 19 populations of salamanders in America, and the greenish warbler in Asia, but many so-called ring species have turned out to be

13625-508: The same species. This concept was narrowed in 2006 to a similarity of 98.7%. The average nucleotide identity (ANI) method quantifies genetic distance between entire genomes , using regions of about 10,000 base pairs . With enough data from genomes of one genus, algorithms can be used to categorize species, as for Pseudomonas avellanae in 2013, and for all sequenced bacteria and archaea since 2020. Observed ANI values among sequences appear to have an "ANI gap" at 85–95%, suggesting that

13750-529: The same species. When two species names are discovered to apply to the same species, the older species name is given priority and usually retained, and the newer name considered as a junior synonym, a process called synonymy . Dividing a taxon into multiple, often new, taxa is called splitting . Taxonomists are often referred to as "lumpers" or "splitters" by their colleagues, depending on their personal approach to recognising differences or commonalities between organisms. The circumscription of taxa, considered

13875-437: The ships shifted back to the Bering Strait region, where the majority of the fleet cruised during the summer until the early 20th century. An estimated 18,600 bowheads were killed in the Bering Strait region between 1848 and 1914, with 60% of the total being reached within the first two decades. An estimated 18,000 bowheads were killed in the Sea of Okhotsk during 1847–1867, 80% in the first decade. Bowheads were first taken along

14000-502: The species concept and making taxonomy unstable. Yet others defend this approach, considering "taxonomic inflation" pejorative and labelling the opposing view as "taxonomic conservatism"; claiming it is politically expedient to split species and recognise smaller populations at the species level, because this means they can more easily be included as endangered in the IUCN red list and can attract conservation legislation and funding. Unlike

14125-485: The theoretical difficulties. If species were fixed and clearly distinct from one another, there would be no problem, but evolutionary processes cause species to change. This obliges taxonomists to decide, for example, when enough change has occurred to declare that a lineage should be divided into multiple chronospecies , or when populations have diverged to have enough distinct character states to be described as cladistic species. Species and higher taxa were seen from

14250-873: The time of Aristotle until the 18th century as categories that could be arranged in a hierarchy, the great chain of being . In the 19th century, biologists grasped that species could evolve given sufficient time. Charles Darwin 's 1859 book On the Origin of Species explained how species could arise by natural selection . That understanding was greatly extended in the 20th century through genetics and population ecology . Genetic variability arises from mutations and recombination , while organisms themselves are mobile, leading to geographical isolation and genetic drift with varying selection pressures . Genes can sometimes be exchanged between species by horizontal gene transfer ; new species can arise rapidly through hybridisation and polyploidy ; and species may become extinct for

14375-480: The time of death was estimated at between 115 and 130 years. Spurred by this discovery, scientists measured the ages of other bowhead whales; one specimen was estimated to be 211 years old. Other bowhead whales were estimated to be between 135 and 172 years old. This discovery showed the longevity of the bowhead whale is much greater than originally thought. Researchers at CSIRO , Australia's national science agency, estimated that bowhead whales' maximum natural lifespan

14500-799: The two seas. The most endangered but historically largest of all bowhead populations is the Svalbard/Spitsbergen population. Occurring normally in Fram Strait , Barents Sea and Severnaya Zemlya along Kara Sea to Laptev Sea and East Siberian Sea regions, these whales were seen in entire coastal regions in European and Russian Arctic, even reaching to Icelandic and Scandinavian coasts and Jan Mayen in Greenland Sea , and west of Cape Farewell and western Greenland coasts. Also, bowheads in this stock were possibly once abundant in areas adjacent to

14625-410: The water. The bowhead whale has paired blowholes at the highest point of the head, which can spout a blow 6.1 m (20 ft) high. The bowhead's blubber is the thickest of any animal's, with a maximum of 43–50 cm (17–20 in). Unlike most cetaceans, the bowhead does not have a dorsal fin —an adaptation for spending much time under sea-surface ice. Like the sperm whale and other cetaceans,

14750-455: The way the sandwiched tubular structures are packed together. Hydrated versus dry whale baleen also exhibit significantly different parallel and perpendicular compressive stress to compressive strain response. Although parallel loading for both hydrated and dry samples exhibit higher stress response (about 20 MPa and 140 MPa at 0.07 strain for hydrated and dry samples respectively) than that for perpendicular loading, hydration drastically reduced

14875-419: The whale must cool itself to prevent hyperthermia (and ultimately brain damage). This organ becomes engorged with blood, and as the whale opens its mouth cold seawater flows over the organ, thus cooling the blood. The bowhead whale is not a social animal, typically travelling alone or in small pods of up to six. It is able to dive and remain submerged under water for up to an hour. The time spent under water in

15000-747: The whale's genome . Through comparative analysis, two alleles that could be responsible for the whale's longevity were identified. These two specific gene mutations linked to the bowhead whale's ability to live longer are the ERCC1 gene and the proliferating cell nuclear antigen ( PCNA ) gene. ERCC1 is linked to DNA repair and increased cancer resistance. PCNA is also important in DNA repair. These mutations enable bowhead whales to better repair DNA damage, allowing for greater resistance to cancer. The whale's genome may also reveal physiological adaptations such as having low metabolic rates compared to other mammals. Changes in

15125-537: The wild. It is difficult to define a species in a way that applies to all organisms. The debate about species concepts is called the species problem. The problem was recognised even in 1859, when Darwin wrote in On the Origin of Species : I was much struck how entirely vague and arbitrary is the distinction between species and varieties. He went on to write: No one definition has satisfied all naturalists; yet every naturalist knows vaguely what he means when he speaks of

15250-476: Was severely reduced before a 1966 moratorium was passed to protect the species. Of the five stocks of bowhead populations, three are listed as " endangered ", one as " vulnerable ", and one as "lower risk, conservation dependent" according to the IUCN Red List . The global population is assessed as of least concern . Carl Linnaeus named this species in the tenth edition of his Systema Naturae (1758). It

15375-636: Was allegedly nearly 21.3 m (70 ft) long. In 1850, an American vessel claimed to have caught a 24.54 m ( 80 + 1 ⁄ 2  ft) individual in the Western Arctic. Whether these lengths were actually measured is questionable. The longest reliably measured were a male of 16.2 m (53 ft) and a female of 18 m (59 ft), both landed in Alaska. On average, female bowheads are larger than males. The adults would have likely measured 19 m (62 ft) in length and 80 t (88 short tons; 79 long tons) in body mass, but larger individuals (like

15500-464: Was derived from analyzing maternal lineage using mitochondrial DNA . Whaling and climatic cooling during the Little Ice Age , from the 16th century to the 19th, is supposed to have reduced the whales' summer habitats, which explains the loss of genetic diversity. A 2013 discovery has clarified the function of the bowhead's large palatal retial organ. The bulbous ridge of highly vascularized tissue,

15625-461: Was seemingly identical to its relatives in the North Atlantic, North Pacific, and Southern Oceans , and as such they were all thought to be a single species, collectively known as the "right whale", and given the binomial name Balaena mysticetus . Today, the bowhead whale occupies a monotypic genus , separate from the right whales , as proposed by the work of John Edward Gray in 1821. For

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