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What the sources say

Common StarfishAsterias rubens

Every figure, record and mechanism on the Common Starfish profile was written from a source, and this is the working table behind it: 46 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

MarLIN, the Marine Life Information Network

Common starfish (Asterias rubens). MarLIN, the Marine Life Information Network.

The page sayspries open mussels with its suction feet, then pushes its stomach inside the shell to digest them
The source saysforcing the bivalve's shell open with its tube feet, the tips of which attach to the bivalve shell by suction. Once a tiny gap (<0.1 mm) is established between the valves of the prey species shell, the starfish everts its stomach lobes into the bivalve and commences digestionNote: tagline
The page saysRocky shores and seabeds of the north-east Atlantic, from Arctic Norway to Senegal, from the shore down to 650 m
The source saysAbundant throughout the north-east Atlantic, from Arctic Norway, along Atlantic coasts to Senegal ... Intertidal to depths of 650 m.Note: stats.habitat; depth claimed separately
The page saysIt lives from the shore down to depths of 650 m.
The source saysIntertidal to depths of 650 m.Note: body
The page saysfrom the shore down to 650 m
The source saysIntertidal to depths of 650 m.Note: stats.habitat
The page saysRocky shores and seabeds
The source saysAsterias rubens occurs in varying abundance upon a variety of substrata that include coarse and shelly gravel and rockNote: stats.habitat; rock substrata plus intertidal range
The page saysMolluscs, worms, other echinoderms and carrion
The source sayspreys upon a wide range of living organisms and carrion that include molluscs, polychaete worms and other echinodermsNote: stats.diet
The page saysPushes its stomach into a mussel shell and digests the meal inside
The source saysthe starfish everts its stomach lobes into the bivalve and commences digestionNote: stats.superpower
The page saysIt grips the shell with its tube feet
The source saysforcing the bivalve's shell open with its tube feet, the tips of which attach to the bivalve shell by suction
The page saysOnce it opens a gap of less than 0.1 mm, it everts its stomach lobes into the shell
The source saysOnce a tiny gap (<0.1 mm) is established between the valves of the prey species shell, the starfish everts its stomach lobes into the bivalve and commences digestion
The page saysAsterias rubens can regenerate an arm within 1 to 2 years.
The source saysAsterias rubens can regenerate an arm within 1-2 years
The page saysIt is the most common and familiar starfish in the north-east Atlantic.
The source saysAsterias rubens is the most common and familiar starfish in the north-east Atlantic region
The page saysIt may grow up to 52 cm across, but 10 to 30 cm is usual.
The source saysmay grow up to 52 cm in diameter, but commonly 10-30 cm
The page saysusually orange, pale brown or violet, and deep-water animals are pale
The source saysvariable in colour, though usually orange, pale brown or violet. Deep-water specimens are pale
The page saysA review of its biology gives a lifespan of seven to eight years, citing a 1972 study.
The source saysAccording to Schafer (1972), the lifespan of Asterias rubens is seven to eight years
The page saysThe same review lists 5 to 10 years in its table.
The source saysLife span 5-10 years
The page saysThe species is abundant from Arctic Norway down the Atlantic coasts to Senegal, and is only found occasionally in the Mediterranean.
The source saysAbundant throughout the north-east Atlantic, from Arctic Norway, along Atlantic coasts to Senegal, and only found occasionally in the Mediterranean
The page saysfound on all British and Irish coasts, especially among beds of mussels and barnacles
The source saysFound on all British and Irish coasts, especially amongst beds of mussels and barnacles
The page saysIt has a well-developed sense of smell, with preferences and avoidances.
The source sayshas a well-developed olfactory sense with adaptive preferences and avoidances
The page saysIt moves into a water current, and moves harder into it when living prey such as a mussel is nearby.
The source saysdemonstrates positive rheotaxis (purposeful movement of a motile organism into a water current), which is enhanced in the presence of living prey such as Mytilus edulisNote: enhanced = stronger
The page sayssome other seabed animals avoid it
The source saysOther species of the benthic fauna, including prey species Marthasterias glacialis , Buccinum undatum and several species of ophiuroids, demonstrate avoidance reactions in the presence of the predatory starfish Asterias rubens
The page saysThey can detect it as it releases a surface-active saponin, a soapy chemical, from its body surface.
The source saysThese species can detect Asterias rubens owing to the release of a surface-active saponin from its body surface
The page saysYes. A review of the species says individuals can survive the loss of one or more arms, and that even a detached arm is likely to survive.
The source saysAlthough individuals can survive loss of one or more arms
The page sayseven a detached arm is likely to survive
The source saysthe remaining starfish and even detached arms are likely to survive
The page saysSexes are separate and fertilization happens in open water.
The source saysAsterias rubens is dioecious. The female produces small eggs that are released into the sea and fertilized externally
The page saysA female of 140 mm across is estimated to spawn 2.5 million eggs
The source saysIt has been estimated that a female starfish of 140 mm diameter can spawn 2.5 million eggs
The page sayswhich develop into plankton-feeding larvae
The source saysreleased into the sea and fertilized externally to develop as planktotrophic larvaeNote: planktotrophic = plankton-feeding; FAQ ref is MarLIN
The page saysIt eats a wide range of living prey and carrion, including molluscs, worms and other echinoderms.
The source sayspreys upon a wide range of living organisms and carrion that include molluscs, polychaete worms and other echinodermsNote: body
The page saysfeeds by pushing its stomach into a mussel once the gap is under 0.1 mm
The source saysOnce a tiny gap (<0.1 mm) is established between the valves of the prey species shell, the starfish everts its stomach lobes into the bivalveNote: vibe.reason

Source
02

Animal Diversity Web

Asterias rubens. Animal Diversity Web.

The page saysA headless starfish that pries open mussels with its suction feet
The source sayshas no head, but its mouth can be found on the lower, oral side of the bodyNote: tagline
The page sayshas no head and no jaws or teeth
The source sayshas neither jaws nor teeth
The page sayshas no head
The source sayshas no head, but its mouth can be found on the lower, oral side of the body where the ambulacral grooves from each arm meet
The page saysIts mouth is on the underside, where the grooves from its five arms meet.
The source saysits mouth can be found on the lower, oral side of the body where the ambulacral grooves from each arm meet
The page saysfive arms
The source sayshas a body which consists of a central disk with five arms radiating from it
The page saysthe starfish waits until the prey is a soft mass before it pulls its stomach back in
The source saysit must wait until the prey is digested into a soft mass before it pulls its stomach back inside of its body
The page saysat the end of each arm sits an eye spot
The source saysAt the end of each arm an eye spot can be found which allows the starfish to sense light
The page saysaverage pace at six inches per minute in a straight line
The source saysmoves at an average of six inches per minute in a straight line
The page saysNo. Animal Diversity Web says it has no poisons or bites that could harm swimmers.
The source saysIt does not have poisons or bites that could be harmful to swimmers
The page saysBivalves are a prominent food source for it.
The source saysThese are the prominent food source of
The page saysNot Evaluated
The source saysIUCN Red List No special statusNote: stats.conservationStatus; no Red List assessment found by prefetch
The page sayspries open mussels
The source saysmakes use of its strong arms and tube feet while preying on bivalves like musselsNote: tagline, superpower, body 'eat a mussel'
The page saysThen it pulls.
The source saysThe arms then pull the two halves of the shell apart exposing the inside of the shellNote: body
The page saysthe tiny sucker-tipped feet that cover its body
The source saysAsterias rubens is covered in tube feet which help in locomotion, respiration, and with suctionNote: body
The page sayssucker-tipped
The source saysOn the end of each of its tube feet lies a vacuum-cup suckerNote: body
The page saysturning its stomach inside out
The source saysThe stomach, turned inside out, goes into the gap between the shell halvesNote: body gloss
The page saysThe meal is digested right there in the mussel.
The source saysget its stomach inside the shell and wrap it around the soft body of the prey. At this time gastric juices are expelled, allowing for the process of digestion to occurNote: body
The page saysIt moves at an average of six inches per minute
The source saysmoves at an average of six inches per minute in a straight lineNote: vibe.reason

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.