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What the sources say

Colossal SquidMesonychoteuthis hamiltoni

Every figure, record and mechanism on the Colossal Squid profile was written from a source, and this is the working table behind it: 43 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

Mesonychoteuthis hamiltoni. Animal Diversity Web, University of Michigan.

The page saysIts lifespan is unknown.
The source saysthe lifespan of the organism is currently unknownNote: ADW's account is old; the 2017 review in the next sentence shows the squid's age still could not be measured in 2017
The page saysAnimal Diversity Web lists no known adverse effects of Mesonychoteuthis hamiltoni on humans
The source saysThere are no known adverse affects of M. hamiltoni on humans.
The page saysnotes that its range is remote
The source saysBecause of its remote range, it is unlikely that this species has much of a negative economic effect on humans.

Source
02

Museum of New Zealand Te Papa Tongarewa

How big is the colossal squid on display? Museum of New Zealand Te Papa Tongarewa.

The page saysOnce it had thawed, scientists at Te Papa Museum measured it at 4.2 meters long, with a 2.5-meter mantle (its main body) and a weight of 495 kilograms
The source saysOnce the colossal squid specimen had completely thawed and been unfolded in the tank, the scientists were able to take measurements. ... They came up with a final total length of 4.2 metres. ... The mantle length of the tank colossal squid was measured at 2.5 metres. ... the tank colossal weighs 495 kilogrammesNote: 'its main body' is a gloss explaining 'mantle'
The page saysEarly guesses had put it at eight to 10 meters
The source saysOriginal estimates of the length were between eight and 10 metres.
The page saysA squid caught in 2003 weighed only 300 kilograms yet measured a longer 5.4 meters overall
The source saysthe tank colossal weighs 495 kilogrammes, while the 2003 specimen weighed only 300 kilogrammes, but had a total length of 5.4 metres.
The page saysTe Papa says that suggests colossal squid vary a lot naturally, and that their size also changes a lot depending on how a body is treated after death
The source saysThis suggests that colossal squid are incredibly plastic animals. ... In addition to this natural variation, the dimensions of colossal squid obviously change considerably, depending on how the specimens are treated after they have died.

Source
03

Museum of New Zealand Te Papa Tongarewa

The eyes of the colossal squid. Museum of New Zealand Te Papa Tongarewa.

The page sayseyes about the size of a soccer ball
The source saysIn a living colossal squid they measure about 27 cm across — about the size of a soccer ball.
The page saysabout 27 centimeters (10.6 inches) across
The source saysIn a living colossal squid they measure about 27 cm acrossNote: 27 cm converted to 10.6 inches; the source doesn't give the inch figure
The page saysA living colossal squid's eyeballs measure about 27 centimeters across, roughly the size of a soccer ball
The source saysIn a living colossal squid they measure about 27 cm across — about the size of a soccer ball.

Source
04

Te Papa Blog

Colossal squid: Hooks and suckers. Te Papa Blog.

The page saystentacle hooks that swivel up to 720 degrees
The source saysThe hooks can swivel 360 to 720 degrees
The page saystentacle-club hooks that can swivel 360 to 720 degrees to keep their grip on prey
The source saysThe hooks can swivel 360 to 720 degrees, but it is not known whether the squid actively controls each hook individually, or whether the hooks swivel passively once latched onto the prey, in order to keep the best grip. There are 22 to 25 hooks in two rows on the middle part (manus) of the tentacle club
The page saysEach of its two long tentacles ends in a club with 22 to 25 hooks that can swivel 360 to 720 degrees to keep the best grip on prey
The source saysIt possesses hooks on each of the eight arms, and also on the two long tentacles ... The hooks can swivel 360 to 720 degrees, but it is not known whether the squid actively controls each hook individually, or whether the hooks swivel passively once latched onto the prey, in order to keep the best grip. There are 22 to 25 hooks in two rows on the middle part (manus) of the tentacle club
The page saysThe hooks on its eight arms do not swivel
The source saysThe arm hooks (below) do not swivel.
The page saysThey sit in very muscular sheaths, most have a strong main claw plus two smaller points, and they likely help hold struggling prey still while it is eaten
The source saysThe arm hooks are set in fleshy, very muscular sheaths and are strongly attached to the arms. They are likely to assist in holding and immobilising struggling prey as it is being killed and eaten. Most of the arm hooks have the main strong 'claw' ..., and also two smaller auxiliary cusps closer to the hook's base, making them three-pointed
The page saysThe two long tentacles end in clubs armed with 22 to 25 hooks that can swivel 360 to 720 degrees to keep the best grip on prey
The source saysThe hooks can swivel 360 to 720 degrees, but it is not known whether the squid actively controls each hook individually, or whether the hooks swivel passively once latched onto the prey, in order to keep the best grip. There are 22 to 25 hooks in two rows on the middle part (manus) of the tentacle club
The page saysThe hooks on the eight arms are different: they do not swivel, most are three-pointed, and they sit in very muscular sheaths
The source saysthe arm-hooks and tentacle-hooks are very different. ... The arm hooks (below) do not swivel. ... The arm hooks are set in fleshy, very muscular sheaths ... Most of the arm hooks have the main strong 'claw' ..., and also two smaller auxiliary cusps closer to the hook's base, making them three-pointed
The page saysThey likely help hold struggling prey still while it is eaten
The source saysThey are likely to assist in holding and immobilising struggling prey as it is being killed and eaten.

Source
05

McClain et al. 2015

McClain et al. (2015). Sizing ocean giants: patterns of intraspecific size variation in marine megafauna. PeerJ.

The page saysThe heaviest invertebrate documented
The source saysHeaviest Cephalopod and Invertebrate: Colossal Squid, Mesonychoteuthis hamiltoni ( Robson, 1925 )
The page saysis the heaviest invertebrate documented, yet by 2015 only 12 complete specimens were known
The source saysHeaviest Cephalopod and Invertebrate: Colossal Squid, Mesonychoteuthis hamiltoni ( Robson, 1925 ) Of all the marine megafauna listed here, we found the least information for Mesonychoteuthis hamiltoni . Only 12 complete specimens are knownNote: 2015 is the paper's publication year from the reference, dating the count
The page saysThe best-preserved adult was caught by the New Zealand fishing vessel San Aspiring in the Ross Sea in 2007
The source saysThe best preserved and most complete adult specimen was caught on February 22, 2007 by the New Zealand fishing vessel San Aspiring while fishing for Antarctic toothfish in the Ross Sea.
The page saysThe best-preserved adult specimen, caught by the fishing vessel San Aspiring in the Ross Sea in 2007, had a total length of 4.2 meters with a 2.5-meter mantle and weighed 495 kilograms, figures confirmed by New Zealand's Te Papa Museum
The source saysThe best preserved and most complete adult specimen was caught on February 22, 2007 by the New Zealand fishing vessel San Aspiring while fishing for Antarctic toothfish in the Ross Sea. The total length, including the mantle and tentacles, was 4.2 m with a mantle length of 2.5 m. The total mass was reported as 495 kg. The measurements were confirmed by the Te Papa Museum
The page saysA smaller specimen caught in 2003 weighed 300 kilograms but measured a longer 5.4 meters overall
The source saysIn 2003, a smaller specimen by mass (300 kg) but with a longer total length of 5.4 m was captured.
The page saysBy 2015, only 12 complete specimens of the species were known
The source saysOnly 12 complete specimens are known (another 4 are known from just a fin, mantle, arms, or tentacles) and six of these are juveniles or subadults.Note: 2015 is the paper's publication year from the reference, dating the count

Source
06

Rosa et al. 2017

Rosa et al. (2017). Biology and ecology of the world's largest invertebrate, the colossal squid (Mesonychoteuthis hamiltoni): a short review. Polar Biology.

The page saysThought to include Patagonian toothfish, lanternfish (myctophids), sleeper sharks, and other squid
The source saysIt has been suggested that M. hamiltoni feeds on myctophids, Patagonian ... toothfish, sleeper sharks and other squidsNote: 'lanternfish' is the common name glossing the source's 'myctophids'
The page saysMostly the mid-depth and deep waters (meso- and bathypelagic zones) of the Southern Ocean around Antarctica
The source saysThis squid is known to be endemic off the Southern Ocean (SO), ... with a circumpolar distribution spreading from the Antarctic continent up to the ... Sub‐Antarctic Front. ... this giant spends most part of ... its life in the meso‐ and bathypelagic realmsNote: 'mid-depth' glosses meso(pelagic); 'around Antarctica' is the source's 'circumpolar'
The page saysolder juveniles are thought to descend to about 2,000 meters
The source saysthe late juvenile stages are assumed to undergo ... ontogenetic descent to depths reaching 2000m
The page saysThe usual way to age a squid is to count growth rings in a hard structure called a statolith, but a 2017 review found the colossal squid material collected so far was not enough to confirm how often those rings form
The source saysThe most common method for ... measuring growth in cephalopods, and consequent age determination, is counting ... growth increments on statoliths (Lipinski 1986; Rodhouse and Hatfield 1990); ... however, M. hamiltoni material reported to date has not yet been sufficient to ... validate the periodicity of statolith‐ring formation for this species.Note: 2017 is the review's year from the reference; 'confirm how often those rings form' is plain words for 'validate the periodicity of statolith-ring formation'; 'hard structure' glosses statolith
The page saysThe colossal squid lives only in the Southern Ocean, in a ring around Antarctica
The source saysThis squid is known to be endemic off the Southern Ocean (SO), ... with a circumpolar distribution spreading from the Antarctic continent up to the ... Sub‐Antarctic Front.Note: 'lives only in' is the source's 'endemic'; 'a ring around Antarctica' is its 'circumpolar distribution'
The page saysSmall juveniles are mainly found between the surface and 500 meters deep, and older juveniles are thought to sink to around 2,000 meters as they grow
The source saysSmall juveniles (< 40 mm mantle length) are mainly found from ... the surface to 500 m, and the late juvenile stages are assumed to undergo ... ontogenetic descent to depths reaching 2000m.Note: 'as they grow' is plain words for 'ontogenetic'
The page saysColossal squid beaks turn up often in the stomachs of Patagonian toothfish, a fish it is thought to eat, and captured toothfish carry bites and hook scratches matching the squid's
The source saysColossal squid beaks have also been found quite frequently in the Patagonian ... toothfish ( Dissostichus eleginoides ) stomach contents (Fig. 5), and in turn, beak ... shaped bites and scratches from club hooks (matching the colossal squid's) have ... also been found along the bodies of captured Patagonian toothfish ... It has been suggested that M. hamiltoni feeds on myctophids, Patagonian ... toothfish
The page saysA 2017 review says this may suggest each hunts the other
The source saysThis may suggest reciprocal predator‐prey dynamics.Note: 2017 is the review's year from the reference; 'each hunts the other' is plain words for 'reciprocal predator-prey dynamics'
The page saysSperm whales are among its larger predators, yet nitrogen tests, which show where an animal sits in the food chain, place the colossal squid itself among the top predators of the Southern Ocean
The source saysThe larger predators of ... the colossal squids are the sperm whales (Clarke 1980) and the sleeper sharks ... Nitrogen isotopes ratio (δ15N) indicate the consumer's trophic ... position ... Assessment of the nitrogen signatures have demonstrated that M. ... hamiltoni is definitely one of the top predators in the Southern OceanNote: 'where an animal sits in the food chain' glosses 'trophic position'

Source
07

Rosa & Seibel 2010

Rosa & Seibel (2010). Slow pace of life of the Antarctic colossal squid. Journal of the Marine Biological Association of the United Kingdom.

The page saystaken by ambush rather than pursuit
The source saysWe argue that the colossal squid is not a voracious predator capable of high-speed predator–prey interactions. It is, rather, an ambush or sit-and-float predator
The page saysA Slow Pace of Life
The source saysthe squid shows a slow pace of life
The page saysA 2010 study of its metabolism estimated that the colossal squid needs only about 0.03 kilograms of prey a day, and argued that it is not a voracious predator capable of high-speed chases
The source saysHere, we present estimates on the metabolic and energetic demands of this cold-water deep-sea giant. ... Our findings also indicate the squid shows a slow pace of life linked with very low prey requirements (only 0.03 kg of prey per day). We argue that the colossal squid is not a voracious predator capable of high-speed predator–prey interactions.Note: 2010 is the study's publication year from the reference; 'high-speed chases' is plain words for 'high-speed predator-prey interactions'
The page saysInstead it is an ambush or "sit-and-float" predator that uses the hooks on its arms and tentacles to snare prey that comes near without noticing it
The source saysIt is, rather, an ambush or sit-and-float predator that uses the hooks on its arms and tentacles to ensnare prey that unwittingly approach.
The page saysa sit-and-float ambush predator whose metabolism is estimated to need only about 0.03 kilograms of prey a day
The source saysvery low prey requirements (only 0.03 kg of prey per day) ... It is, rather, an ambush or sit-and-float predatorNote: vibe.reason; 'metabolism' because the estimate comes from the study's metabolic-rate measurements

Source
08

Nilsson et al. 2012

Nilsson et al. (2012). A Unique Advantage for Giant Eyes in Giant Squid. Current Biology.

The page saysAlong with the giant squid, the largest eyes in the animal kingdom
The source saysGiant and colossal deep-sea squid (Architeuthis and Mesonychoteuthis) have the largest eyes in the animal kingdom
The page saysAlong with the giant squid, it has the largest eyes in the animal kingdom
The source saysGiant and colossal deep-sea squid (Architeuthis and Mesonychoteuthis) have the largest eyes in the animal kingdom
The page saysA 2012 study photographed a giant squid eye of about 27 centimeters and predicted that, below 600 meters deep, an eye like that could detect a sperm whale more than 120 meters away
The source saysWe also provide photographic documentation of an eyeball of about 27 cm with a 9 cm pupil in a giant squid, and we predict that, below 600 m depth, it would allow detection of sperm whales at distances exceeding 120 m.Note: 2012 is the study's publication year from the reference
The page saysThe study's theory says eyes this big are unlikely to evolve for spotting mates or prey far off, and are instead uniquely suited to spotting very large predators such as sperm whales
The source saysHere we develop a theory for visual detection in pelagic habitats, which predicts that such giant eyes are unlikely to evolve for detecting mates or prey at long distance but are instead uniquely suited for detecting very large predators, such as sperm whales.

Source
09

Barratt & Allcock 2014

Barratt & Allcock (2014). Mesonychoteuthis hamiltoni. The IUCN Red List of Threatened Species 2014: e.T163170A980001.

The page saysIt is rated Least Concern on the IUCN Red List
The source saysIUCN Red List category: Least Concern (LC).

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.