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What the sources say

Greenland SharkSomniosus microcephalus

Every figure, record and mechanism on the Greenland Shark profile was written from a source, and this is the working table behind it: 62 claims checked word for word against these sources. The left column is what the page says. The right column is the source's own words, copied, not paraphrased; a ... marks a cut and[brackets] an insertion. Open any source and check it yourself.

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Source
01

Animal Diversity Web, University of Michigan

Somniosus microcephalus (Greenland shark). Animal Diversity Web, University of Michigan.

The page sayslives in water as cold as 1 degree Celsius
The source saysin waters from 1 to 12 degrees Celsius
The page saysit eats cod, herring, skates, seals, and small whales
The source saysFish include herring (Clupeinae), salmon (Salmonidae), smelt (Osmeridae), cod (Gadidae), pollock (Theragra), haddock (Melanogrammus), halibut (Hippoglossus), redfish (Hoplostethus), sculpins (Cottoidei), lumpfish (Cyclopterus), and skates (Rajiformes). Seals (Phocidae) and small whales (Delphinidae) are also common food items.
The page saysdrowned horses and reindeer have turned up in the stomachs of captured sharks
The source saysDrowned horses and reindeer have also been found in the stomachs of captured specimens.
The page saysMany Greenland sharks have a copepod, Ommatokoita elongata, attached to the cornea of one eye
The source saysMany of these sharks have copepod parasites ... attached to the corneas of their eyes. A single, female copepod will attach itself to one of the corneas
The page saysbut that does not seem to harm the shark, since it does not rely on its vision
The source saysThis does not seem to negatively effect the shark, as they do not rely on their vision.
The page saysCod, herring, skates
The source saysherring (Clupeinae), salmon (Salmonidae), smelt (Osmeridae), cod (Gadidae) ... and skates (Rajiformes)Note: stats.diet
The page saysseals, and small whales, plus carrion such as reindeer and horse carcasses
The source saysSeals (Phocidae) and small whales (Delphinidae) are also common food items ... Drowned horses and reindeer have also been found in the stomachs of captured specimens.Note: stats.diet
The page saysMany Greenland sharks have a parasitic copepod, Ommatokoita elongata, attached to one eye
The source saysMany of these sharks have copepod parasites ... attached to the corneas of their eyes. A single, female copepod will attach itself to one of the corneasNote: faq 3; replaces 'On most Greenland sharks ... usually', which read Florida's one-eye-per-shark sentence as a prevalence figure
The page saysno attack on a person has been confirmed
The source saysHowever, no attacks on humans by this species have been confirmed.Note: body; the sentence stats.dangerLevel: Medium rests on

Source
02

National Ocean Service, NOAA

How long do Greenland sharks live? National Ocean Service, NOAA.

The page saysgrowing under a centimeter a year
The source saysthe sharks grow at a very slow rate (less than 1 cm per year)Note: tagline
The page sayscruises the deep, cold water
The source saysan adaptation to the deep, cold waters it inhabits
The page saysIts skeleton has no hard, calcified tissue to grow rings on, the way other sharks are aged
The source saysThe age of other shark species can be estimated by counting growth bands on fin spines or on the shark's vertebrae ... Greenland sharks, however, have no fin spines and no hard tissues in their bodies. Their vertebrae are too soft to form the growth bands seen in other sharks.
The page saysproteins formed before birth that do not degrade with age
The source saysInside the shark's eyes, there are proteins that are formed before birth and do not degrade with age
The page saysThe largest shark in the study, a five-meter female, worked out to somewhere between 272 and 512 years old
The source saysThe largest shark they found, a 5-meter female, was between 272 and 512 years old according to their estimates.Note: matches Nielsen 2016's own figure for its largest specimen (502 cm, 392 ± 120 years = 272-512 years)
The page saysA Greenland shark grows less than a centimeter a year
The source saysthe sharks grow at a very slow rate (less than 1 cm per year)
The page saysis known to dive as deep as 2,200 meters
The source saysthese sharks are known to dive as deep as 2,200 meters
The page saysIt grows less than a centimeter a year
The source saysthe sharks grow at a very slow rate (less than 1 cm per year)Note: stats.superpower
The page saysknown to dive as deep as 2,200 meters
The source saysthese sharks are known to dive as deep as 2,200 metersNote: stats.habitat
The page saysthat other sharks are aged by, so there are no growth rings to count
The source saysThe age of other shark species can be estimated by counting growth bands on fin spines or on the shark's vertebrae ... Their vertebrae are too soft to form the growth bands seen in other sharks.Note: faq 1; replaces 'because Greenland sharks have no bones', a cause no source gives (no shark has bones, yet other sharks are aged)
The page saysThe largest shark in the study, a five-meter female, worked out to somewhere between 272 and 512 years old
The source saysThe largest shark they found, a 5-meter female, was between 272 and 512 years old according to their estimates.Note: faq 1; the FAQ's ref states it too: 'the largest animal (502 cm) to be 392 ± 120 years old'

Source
03

Florida Museum of Natural History, Discover Fishes

Somniosus microcephalus. Florida Museum of Natural History, Discover Fishes.

The page saysof the North Atlantic and Arctic Ocean
The source saysThe shark is typically found in the Northern Atlantic and Arctic regions.
The page saysswims slowly
The source saysit is a slow swimmer
The page saysGreenland sharks average roughly 2.4 to 4.3 meters long
The source saysGreenland sharks average in size from 244 to 427 cmNote: 244 cm = 2.44 m, 427 cm = 4.27 m, rounded to 2.4 and 4.3; ADW gives the same 'Average length 244 to 427 cm'
The page saysthe biggest reach about 6.4 meters
The source saysThis shark reaches a maximum length of about 640 cm (21 feet)Note: 640 cm = 6.4 m; replaces 'the largest confirmed Greenland shark stretched 6.4 meters', which turned the top of ADW's length range into a confirmed record
The page saysFemales are the larger sex
The source sayswith females being the larger sex
The page saysplus eels, flounders, and other small sharks
The source saysThe shark's most common food consists of a large variety of ocean dwellers such as other small sharks, skates, eels, herring, capelin, char, various gadoids, redfish, sculpins, lumpfish, wolfish, and flounders.
The page saysIt is a slow swimmer that likely ambushes its prey, and it eats carrion too
The source saysit is a slow swimmer, and likely ambushes its prey and scavenges for carrion
The page saysCold North Atlantic and Arctic Ocean waters
The source saysThe shark is typically found in the Northern Atlantic and Arctic regions.Note: stats.habitat
The page saysfrom the surface to about 1,200 meters, in water between 1 and 12 degrees Celsius
The source saysThe shark ranges in depths of 0-3,937 feet (0 to 1,200 m) and temperatures of 34-68°F (1 to 12°C).Note: stats.habitat; Florida states the range for the species, where ADW's identical figures are scoped to 'northern parts of their range'
The page sayseels
The source saysother small sharks, skates, eels, herringNote: stats.diet
The page saysthe International Shark Attack File lists only one reported attack
The source saysAccording to the International Shark Attack File (ISAF) there has only been one reported attack of the Greenland shark on a human.Note: body; stats.dangerLevel
The page saysswims slowly
The source saysit is a slow swimmerNote: vibe.reason (women artists, round 2)

Source
04

Nielsen et al. 2016

Nielsen et al. (2016). Eye lens radiocarbon reveals centuries of longevity in the Greenland shark (Somniosus microcephalus). Science.

The page saysThe longest-lived vertebrate known to science
The source saysthe Greenland shark is the longest-lived vertebrate known
The page sayswith females not sexually mature until at least 156 years old, give or take 22
The source saysas females are reported to reach sexual maturity at lengths >400 cm ... the corresponding age would be at least 156 ± 22Note: tagline; female scope and the ± 22 restored (the estimate is for females, whose maturity length is >400 cm)
The page saysit grows slowly
The source saysgrows slowly and reaches >500 centimeters (cm) in total length
The page sayslives longer than any other backboned animal known
The source saysthe Greenland shark is the longest-lived vertebrate known
The page saysno hard, calcified tissue
The source saysConventional growth zone chronologies cannot be used to age Greenland shark due to the lack of calcified tissues
The page saysIn 2016, researchers found a workaround
The source saysThe definitive version was published in Science on vol. 353, issue 6300. Aug. 12, 2016Note: body; sources the bare '2016' figure to the paper's publication date
The page saysthe center of a shark's eye lens is made of proteins formed before birth
The source saysthe eye lens nucleus is composed of metabolically inert crystalline proteins, which in the center (i.e., the embryonic nucleus) is formed during prenatal development
The page saysBy radiocarbon-dating the eye lenses of 28 female Greenland sharks, a team calculated a lifespan of at least 272 years, making it the longest-lived vertebrate known
The source saysRadiocarbon dating of eye lens nuclei from 28 female Greenland sharks (81 to 502 cm in total length) revealed a life span of at least 272 years ... Our results show that the Greenland shark is the longest-lived vertebrate known
The page saysthe same data put sexual maturity in females at no younger than 156 years old, give or take 22
The source saysas females are reported to reach sexual maturity at lengths >400 cm ... the corresponding age would be at least 156 ± 22Note: scope: females only, from the same 28-shark chronology; '± 22' restored
The page saysfemales aren't sexually mature until at least 156 years old, give or take 22
The source saysas females are reported to reach sexual maturity at lengths >400 cm ... the corresponding age would be at least 156 ± 22Note: stats.superpower
The page saysits lifespan runs to at least 272 years, the longest of any known vertebrate
The source saysrevealed a life span of at least 272 years ... the Greenland shark is the longest-lived vertebrate knownNote: stats.superpower; replaces 'can live past 272 years' ('past' for 'at least') and the unsourced 'A metabolism so slow' cause (NOAA offers slow metabolism only as 'one theory')
The page saysGreenland sharks lack the calcified tissue
The source saysConventional growth zone chronologies cannot be used to age Greenland shark due to the lack of calcified tissuesNote: faq 1
The page saysIn a 2016 study
The source saysThe definitive version was published in Science on vol. 353, issue 6300. Aug. 12, 2016Note: faq 1; sources the bare '2016' figure to the paper's publication date
The page saysscientists radiocarbon-dated the eye lenses of 28 female sharks
The source saysRadiocarbon dating of eye lens nuclei from 28 female Greenland sharks (81 to 502 cm in total length)
The page saysthe center of the lens is made of proteins formed before birth
The source saysthe eye lens nucleus is composed of metabolically inert crystalline proteins, which in the center (i.e., the embryonic nucleus) is formed during prenatal developmentNote: faq 1 parenthetical
The page sayscalculated a lifespan of at least 272 years, making it the longest-lived vertebrate known
The source saysrevealed a life span of at least 272 years ... Our results show that the Greenland shark is the longest-lived vertebrate knownNote: faq 1
The page saysgrows slowly
The source saysgrows slowly and reaches >500 centimeters (cm) in total lengthNote: vibe.reason (women artists, round 2)
The page sayshas a lifespan of at least 272 years
The source saysrevealed a life span of at least 272 yearsNote: vibe.reason (women artists, round 2)

Source
05

Nielsen et al. 2020

Nielsen et al. (2020). Assessing the reproductive biology of the Greenland shark (Somniosus microcephalus). PLOS ONE.

The page saystwo in one study weighed 1,100 and 1,367 kilograms
The source saystwo Stage 3 females in our study weighed 1,100 kg and 1,367 kgNote: replaces ADW's 'Range mass 700 to 1000 kg', which cannot cover ADW's own 40-640 cm length range and sits below both of these weighed females
The page saysResearchers estimate a litter could hold up to 200 to 324 pups, depending on the mother's size, each about 35 to 45 centimeters long at birth
The source sayswe estimate up to 200–324 pups per pregnancy (depending on maternal size) with a body length-at-birth of 35–45 cm
The page saysthough that estimate is still waiting to be checked against a pregnant shark
The source saysThese estimates remain to be verified by future observations from gravid Greenland sharks.

Source
06

Anthoni et al. 1991

Anthoni et al. (1991). Poisonings from flesh of the Greenland shark Somniosus microcephalus may be due to trimethylamine. Toxicon.

The page saysGreenland shark flesh, especially fresh, is toxic to both dogs and people
The source saysThe flesh of the Greenland shark, Somniosus microcephalus, especially in fresh condition, is toxic to both dog and man.
The page saysIt carries large amounts of trimethylamine oxide, and the poisoning symptoms appear to come from that chemical breaking down in the gut into trimethylamine
The source saysthe presence of large amounts of trimethylamine oxide (TMAO) but no other substances that could be directly responsible for the poisoning. The symptoms appear to be due to an acute trimethylamine (TMA) poisoning arising from intestinal reduction of TMAO to TMA.
The page saysIts flesh carries large amounts of trimethylamine oxide (TMAO). The poisoning appears to come from TMAO breaking down in the gut into trimethylamine (TMA), and the fresh flesh is toxic to both dogs and people
The source saysthe flesh of the Greenland shark ... is toxic to both dog and man ... the presence of large amounts of trimethylamine oxide (TMAO) ... The symptoms appear to be due to an acute trimethylamine (TMA) poisoning arising from intestinal reduction of TMAO to TMA.

Source
07

Borucinska, Benz & Whiteley 1998

Borucinska, Benz & Whiteley (1998). Ocular lesions associated with attachment of the parasitic copepod Ommatokoita elongata (Grant) to corneas of Greenland sharks, Somniosus microcephalus (Bloch & Schneider). Journal of Fish Diseases.

The page saysIt can scar the cornea and could lead to severe vision loss, possibly blindness
The source saysfibrosis of the corneal substantia propria ... parasitism by O. elongata could lead to severe vision impairment (possibly including blindness) in Greenland sharks
The page saysResearchers who examined infected eyes found corneal ulcers and scarring, and concluded the parasite could lead to severe vision impairment, possibly including blindness
The source sayscorneal epithelial ulceration and heterophilic keratitis ... fibrosis of the corneal substantia propria ... parasitism by O. elongata could lead to severe vision impairment (possibly including blindness) in Greenland sharks
The page saysYet the infected sharks looked otherwise healthy, and the infection doesn't seem to seriously weaken them
The source saysthe otherwise healthy appearance of the infected sharks studied and the information contained in the literature suggests that O. elongata infections do not significantly debilitate the hosts

Source
08

Osimani et al. 2019

Osimani et al. (2019). Unveiling hákarl: A study of the microbiota of the traditional Icelandic fermented fish. Food Microbiology.

The page saysIn Iceland, the flesh is traditionally cured into a fermented dish called hákarl instead of eaten fresh
The source saysHákarl is produced by curing of the Greenland shark (Somniosus microcephalus) flesh, which before fermentation is toxic due to the high content of trimethylamine (TMA) or trimethylamine N-oxide (TMAO).
The page saysIcelanders traditionally cure the meat into a fermented dish called hákarl instead of eating it fresh
The source saysHákarl is produced by curing of the Greenland shark (Somniosus microcephalus) flesh

Source
09

Kulka et al. 2020

Kulka et al. (2020). Somniosus microcephalus. The IUCN Red List of Threatened Species 2020: e.T60213A124452872.

The page saysVulnerable
The source saysIUCN Red List category: Vulnerable (VU).Note: stats.conservationStatus

How the table was made: a writer drafted the profile from these sources and logged each claim with its quote, a reviewer with nothing but this table checked every sentence said no more than its quote, and a script confirmed each quote appears word for word in the source. The method is in the site'sAbout page.