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What the sources say

Common OctopusOctopus vulgaris

Every figure, record and mechanism on the Common Octopus profile was written from a source, and this is the working table behind it: 56 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

Allcock, Headlam & Allen 2018

Allcock, Headlam & Allen (2018). Octopus vulgaris. The IUCN Red List of Threatened Species 2018: e.T162571A918906.

The page saysLeast Concern
The source saysLeast ConcernNote: stats.conservationStatus; assessed 2016 (published in the 2018 release); category read through GBIF's copy of the Red List
The page saysThe IUCN Red List assessment published in 2018 rates Octopus vulgaris as Least Concern.
The source saysLeast ConcernNote: faq; published in the 2018 release (per the DOI); the assessment year is not in the cached text, so it was cut; category read through GBIF's copy of the Red List

Source
02

Messenger 2001

Messenger (2001). Cephalopod chromatophores: neurobiology and natural history. Biological Reviews.

The page sayswhose colour-changing skin is run by over half a million neurons
The source saysIn Octopus vulgaris there are over half a million neurons in the chromatophore lobesNote: tagline; stats.superpower
The page saysSkin patterns carried out by over half a million neurons in the chromatophore lobes of its brain
The source saysat the lowest level, motoneurons in the chromatophore lobes execute the programmes, their activity or inactivity producing the patterning seen in the skin. In Octopus vulgaris there are over half a million neurons in the chromatophore lobesNote: stats.superpower
The page saysCephalopods (the octopus and squid group) change their appearance with chromatophores.
The source saysNeural control of the chromatophores enables a cephalopod to change its appearance almost instantaneously
The page saysEach one is an organ in the skin: an elastic sac of pigment with muscles attached.
The source saysthey are neuromuscular organs rather than cells ... Each chromatophore organ comprises an elastic sacculus containing pigment, to which is attached a set of obliquely striated radial muscles
The page saysWhen the muscles contract, the sac expands. When they relax, the sac springs back using the energy it stored.
The source saysWhen excited the muscles contract, expanding the chromatophore; when they relax, energy stored in the elastic sacculus retracts it.
The page saysthe optic lobes of the brain, which work largely on visual information, choose a body pattern
The source saysAt the highest level, the optic lobes, acting largely on visual information, select specific motor programmes (i.e. body patterns)
The page saysThat plan is carried out by the chromatophore lobes, which in Octopus vulgaris hold over half a million neurons.
The source saysat the lowest level, motoneurons in the chromatophore lobes execute the programmes ... In Octopus vulgaris there are over half a million neurons in the chromatophore lobes
The page saysSkin Run by Half a Million Neurons
The source saysIn Octopus vulgaris there are over half a million neurons in the chromatophore lobesNote: heading

Source
03

FAO Species Catalogue for Fishery Purposes No. 4, Vol. 3

Cephalopods of the world, Volume 3: Octopods and vampire squids. FAO Species Catalogue for Fishery Purposes No. 4, Vol. 3.

The page saysestimated to live one to two years
The source saysLongevity of this species has been estimated in the range of one to two years.Note: tagline
The page saysRocky, sandy and muddy seabeds
The source sayslives on the continental shelf on rocky, sandy or muddy substratesNote: stats.habitat
The page saysfrom the shore down to 250 m
The source saysThis species has been reported from depths ranging from 0 to 250 mNote: stats.habitat
The page saysin the Mediterranean and north-east Atlantic
The source saysOctopus vulgaris sensu stricto Mediterranean Sea, central and north - east Atlantic OceanNote: stats.habitat
The page saysCrustaceans (typically crabs and lobsters), fish and shelled molluscs
The source saysfrom crustaceans (typically crabs and lobsters), to fish (when they can be caught), to a range of shelled molluscsNote: stats.diet
The page saysThe FAO catalogue lists its living colours as yellow brown, red brown, dark brown or grey.
The source saysColour in life variable from yellow brown, to red brown, dark brown or grey.
The page saysThe name Octopus vulgaris has covered look-alike forms in several oceans, which the FAO catalogue calls a species complex in urgent need of revision.
The source saysThe geographically disjunct forms (Fig. 39) are treated here under the following names ... This species complex is in urgent need of revision
The page saystreats Octopus vulgaris in the strict sense as the form of the Mediterranean and the central and north-east Atlantic
The source saysOctopus vulgaris sensu stricto Mediterranean Sea, central and north - east Atlantic Ocean
The page saysthe south coast of England, north-west and west Africa, the Azores, the Canary Islands and the Cape Verde Islands
The source saysSouth coast of England; north - west and west coast of Africa; Azores, Canary Islands and Cape Verde Islands.
The page saysa mantle (body sac) 400 mm long, a total length of around 1.8 m and a weight of over 20 kg
The source says* Based on Mediterranean and north - east Atlantic material (see Remarks above). Size: Mantle length to 400 mm; total length to around 1.8 m; body weight to over 20 kg.
The page saysA common size is a mantle of 250 mm.
The source saysCommon at smaller size (250 mm ML). Geographical Distribution : Mediterranean SeaNote: body
The page saysIts arms are 4 to 5.5 times the mantle length, each with two rows of suckers
The source saysArms long (4 to 5.5 times mantle length)
The page saystwo rows of suckers
The source saysTwo rows of suckers on each arm.
The page saysin larger animals each normal arm carries around 220 to 320 of them
The source saysIn larger animals, around 220 to 320 suckers on each normal arm.
The page saysIts longevity is estimated at one to two years.
The source saysLongevity of this species has been estimated in the range of one to two years.
The page sayson the continental shelf
The source sayslives on the continental shelf on rocky, sandy or muddy substrates
The page saysIt has been recorded from the shoreline to 250 m deep, but typically lives shallower than 100 m.
The source saysreported from depths ranging from 0 to 250 m, but typically occurs shallower than 100 m
The page saysprimarily active at night and typically spends the day in a den
The source saysThis species is primarily night active, typically spending daylight hours within a den.
The page saysa crevice in a reef or one the octopus builds in soft sediment, sometimes using loose rocks or shells
The source saysDens can consist of pre - existing crevices in rocky reefs and rubble or can be constructed by the octopus in softer sediments, sometimes incorporating loose rocks or shells.
The page saysprobes for prey by touch with its upper arm pairs, or wraps its arm crown around a rock and uses the arm tips to detect and flush prey out
The source saysThis species feeds by tactile probing for prey by the dorsal arm pairs or by enveloping rocks within the arm crown and webs and using the arm tips to detect and flush prey.
The page saysCrabs and lobsters are typical meals, fish when it can catch them, and shelled molluscs
The source saysfrom crustaceans (typically crabs and lobsters), to fish (when they can be caught), to a range of shelled molluscs
The page sayswhich it typically gets into by boring a hole with its toothed salivary papillae, paralysing or relaxing the animal inside
The source saysThe latter group typically are extracted by drilling through the shell with the toothed salivary papillae to paralyse/relax the occupant
The page saysCannibalism has been recorded.
The source saysCannibalism also has been recorded for this species.
The page saysIts predators include sharks and many fishes, among them groupers, wrasses and eels.
The source saysA wide range of predators prey on this species including many fishes such as serranid groupers, wrasses and eels, as well as sharks
The page saysA female lays 100,000 to 500,000 eggs in strings cemented to her den roof
The source saysThey produce between 100 000 and 500 000 eggs, which are bound together in strings (festoons) and cemented to the roof of the den.Note: 100 000 to 500 000 in the source
The page saysthen stays, stroking and ventilating them
The source saysThe female then remains with the eggs, constantly ventilating and stroking the eggs
The page saysShe usually goes without food, burns her own muscle for energy and can shed a third or more of her body weight.
The source saysShe typically does not feed during this entire period ... the female digests her own musculature as an energy source and can lose a third or more of her body weight.
The page saysWhen the hatchlings emerge she weakens and dies.
The source saysAs the hatchlings emerge, the female weakens and dies.
The page saysIn cool waters the brooding can take up to 4 to 5 months.
The source sayswhich can take up to 4 - 5 months in cool waters
The page saysThe hatchlings, called paralarvae, are 1 to 2 mm long and transparent.
The source saysHatchlings emerge at around 1 - 2 mm in length ... The hatchlings are known as paralarvae and are transparent
The page saysThey swim straight into open water, where the FAO catalogue says the planktonic (drifting) phase is estimated at weeks to months, depending on temperature and conditions.
The source saysimmediately swim into the water column to commence a planktonic phase ... estimated to be in the order of weeks to months, again dependent on the temperature and other environmental conditions
The page saysOn settling, the young change into a form closer to the adults.
The source saysOn settlement, juveniles metamorphose into a form more typical of the adults
The page saysthe FAO catalogue puts the biggest at around 1.8 m in total length and over 20 kg, with a mantle (body sac) of up to 400 mm
The source says* Based on Mediterranean and north - east Atlantic material (see Remarks above). Size: Mantle length to 400 mm; total length to around 1.8 m; body weight to over 20 kg.Note: faq
The page saysThe FAO catalogue says shelled prey are typically extracted by drilling: toothed salivary papillae bore through the shell to paralyse or relax the mollusc inside.
The source saysThe latter group typically are extracted by drilling through the shell with the toothed salivary papillae to paralyse/relax the occupantNote: faq
The page saysThe FAO catalogue estimates its longevity at one to two years
The source saysLongevity of this species has been estimated in the range of one to two years.Note: faq; the claim says estimated
The page saysevery female dies after a single brooding of her eggs
The source saysAll females die after a single brooding event.Note: faq
The page saysIt is commonly found smaller, with a 250 mm mantle.
The source saysCommon at smaller size (250 mm ML). Geographical Distribution : Mediterranean SeaNote: faq
The page saysLong Arms, Short Life
The source saysArms long (4 to 5.5 times mantle length)Note: heading; "Short Life" rests on the longevity claim (estimated one to two years) in the same section
The page saysNight Shift on the Seabed
The source saysThis species is primarily night active, typically spending daylight hours within a den.Note: heading
The page saysOne Brood, Then the End
The source saysAll females die after a single brooding event.Note: heading; the section is about the female
The page saysA mother's last job
The source saysAs the hatchlings emerge, the female weakens and dies.Note: blockquote lead

Source
04

Fiorito & Scotto 1992

Fiorito & Scotto (1992). Observational Learning in Octopus vulgaris. Science.

The page saysIt can learn by watching.
The source saysThese results show that observational learning can occur in invertebrates.
The page saysIn a 1992 experiment, untrained octopuses watched trained ones pick one of two objects that differed only in colour.
The source saysUntrained Octopus vulgaris (observers) were allowed to watch conditioned Octopus(demonstrators) perform the task of selecting one of two objects that were presented simultaneously and differed only in color.
The page saysTested alone afterwards, the watchers consistently chose the same object as the trained animals had
The source saysAfter being placed in isolation, the observers, in a similar test, consistently selected the same object as did the demonstrators.
The page saysthey learned faster than the trained animals did during their own conditioning
The source sayswas more rapid than the learning that occurred during the conditioning of animals
The page saystags: intelligent
The source saysThese results show that observational learning can occur in invertebrates.Note: tagMetadata: learned behaviour; the elephant's tag rests on a learned task the same way

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.