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What the sources say

Giant ClamTridacna gigas

Every figure, record and mechanism on the Giant Clam profile was written from a source, and this is the working table behind it: 40 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

Dallas World Aquarium

Giant clams. Dallas World Aquarium.

The page saysThe largest living bivalve gets most of its nutrients from algae living in its flesh.
The source saysThis is the largest living bivalve mollusk.Note: tagline; 'most' is the source's 'majority'
The page saysDallas World Aquarium says the majority of its nutrients come from a partnership with billions of algae that live in its tissues.
The source saysthe majority of its nutrients are obtained by a mutually beneficial relationship with billions of algae that live in its tissuesNote: tagline 'lives on their sugars' is cut to the nutrient claim; see report
The page saysPlankton filtered from seawater, plus carbon by-products from the algae living in its tissues
The source saysthe Giant clam filters particulate food, including microscopic marine plants (phytoplankton) and animals (zooplankton)Note: stats.diet
The page saysthe algae hand over the carbon by-products of photosynthesis
The source saysthe clam obtains the carbon by-products of photosynthesisNote: stats.diet
The page saysHosts billions of algae in its own tissues and gets the majority of its nutrients from them
The source saysthe majority of its nutrients are obtained by a mutually beneficial relationship with billions of algae that live in its tissuesNote: stats.superpower
The page saysIn return for shelter from predators
The source saysThe algae gain protection from predators
The page sayspale or clear spots known as windows
The source saysThey also have a number of pale or clear spots on the mantle, known as ‘windows’.
The page saysClear patches on the mantle let sunlight in, and the algae need that light for photosynthesis.
The source saysThese ‘windows’ allow sunlight to filter in through the mantle which is necessary for photosynthesis.
The page saysLight passes through them into the mantle, and photosynthesis by the algae depends on it.
The source saysThese ‘windows’ allow sunlight to filter in through the mantle which is necessary for photosynthesis.Note: FAQ 3
The page saysIt pulls seawater in through one siphon (a hole) and strains out plankton
The source saysThe inhalant siphon is used to draw in seawater that is then filtered for planktonic food.
The page saysThis is the largest living bivalve, a two-shelled mollusc like a mussel or an oyster.
The source saysThis is the largest living bivalve mollusk.Note: source: largest living bivalve mollusk; shell of two valves; mussel/oyster gloss is explanatory
The page saysA fully grown adult can no longer close its shell completely.
The source saysOnce they are fully grown they cannot close their shell completely.
The page saysit is not uncommon for one to pass 100 years
The source saysit is not uncommon for them to live more than 100 years!
The page saysthat living past 100 years is not uncommon for a giant clam, which stays in one spot from the day it settles
The source saysGiant clams are sessile, once they have settled somewhere they remain there for the rest of their life and within their environment it is not uncommon for them to live more than 100 years!Note: FAQ 2
The page saysA giant clam is sessile, meaning it stays put.
The source saysGiant clams are sessile, once they have settled somewhere they remain there for the rest of their life
The page saysIts larvae swim and feed in the water until they are big enough to settle, then they remain in that place for the rest of their lives.
The source saysThe larvae swim and feed in the water column until they are big enough to find somewhere to settle and then they begin their adult life as a sessile clam.
The page saysAdults release eggs and sperm into the water, and fertilisation happens there.
The source saysThey release eggs and sperm into the water, where the eggs are fertilized.
The page saysA giant clam does not feed alone.
The source saysa mutually beneficial relationship with billions of algae that live in its tissuesNote: framing of the algae partnership
The page saysThose pale or clear patches are windows.
The source saysThey also have a number of pale or clear spots on the mantle, known as ‘windows’.Note: FAQ 3
The page saysOnce a giant clam settles, it stays in that spot for the rest of its life
The source saysGiant clams are sessile, once they have settled somewhere they remain there for the rest of their lifeNote: vibe.reason
The page saysdrawing seawater in through a siphon and filtering out plankton
The source saysThe inhalant siphon is used to draw in seawater that is then filtered for planktonic food.Note: vibe.reason

Source
02

NOAA Fisheries

True Giant Clam. NOAA Fisheries.

The page saysShallow reefs, atoll lagoons and fringing reefs of the Indo-Pacific, from Myanmar to Kiribati
The source saysThe geographic range of T. gigas spans the shallow waters of the Indo-Pacific and the Great Barrier Reef, from Myanmar in the west to the Republic of Kiribati in the eastNote: stats.habitat
The page saysShallow reefs, atoll lagoons and fringing reefs
The source sayscan be found in many habitats, including high- and low-islands, atoll lagoons, and fringing reefsNote: stats.habitat; the source lists these among many habitats
The page saysNOAA ranks Tridacna gigas as the biggest of all the giant clam species, growing to more than a metre wide and more than 496 pounds (225 kg).
The source saysis the largest of all the giant clam species, growing to sizes over a meter wide and weights in excess of 496 pounds (225 kg)
The page saysfrom Myanmar to Kiribati and from the Ryukyu Islands of Japan down to Queensland, Australia
The source saysfrom Myanmar in the west to the Republic of Kiribati in the east, and from the Ryukyus Islands of Japan in the north to Queensland, Australia in the south
The page saysNOAA places the species across the Indo-Pacific and the Great Barrier Reef
The source saysspans the shallow waters of the Indo-Pacific and the Great Barrier Reef
The page sayscoral reefs, atoll lagoons and fringing reefs, typically 6 to 65 feet down, often among hard coral or on bare sand
The source saysIndividuals are typically found between the depths of 6 to 65 feet, often among hard coral communities, hard reef substrata, or on bare sand.
The page saysdecades of heavy, unregulated collecting have made it very scarce across much of its range
The source saysDecades of intense, unregulated harvest has driven T. gigas to very low abundance throughout much of its range.
The page sayscatching it for meat and shells is the main threat
The source saysPast and ongoing harvest for meat and shells is the primary threat to this and other giant clam species.
The page saysIn 2024 NOAA Fisheries proposed listing it as endangered under the US Endangered Species Act
The source saysNOAA Fisheries has completed a status review for Tridacna gigas and is proposing to list the species as endangered throughout its range under the Endangered Species ActNote: 2024: the NOAA page stating the proposal was last updated 07/24/2024; dated rather than present tense because the rule may since be final
The page saysit is on CITES Appendix II
The source saysCITES Appendix II Throughout Its Range
The page saysBiggest of its kind
The source saysis the largest of all the giant clam speciesNote: heading
The page saysweightKg: 225
The source saysweights in excess of 496 pounds (225 kg)Note: large adult; the 500 kg record is an outlier

Source
03

Neo & Li 2024

Neo & Li (2024). Tridacna gigas. The IUCN Red List of Threatened Species 2024: e.T22137A119167161.

The page saysCritically Endangered
The source saysIUCN Red List category: Critically Endangered (CR).Note: stats.conservationStatus; assessed 2024; GBIF copy of the Red List
The page saysThe IUCN Red List assessed it as Critically Endangered in 2024.
The source saysIUCN Red List category: Critically Endangered (CR).Note: year from the 2024-2 assessment DOI
The page saysThe IUCN Red List's 2024 assessment of Tridacna gigas rates it Critically Endangered.
The source saysIUCN Red List category: Critically Endangered (CR).Note: FAQ 4

Source
04

Li et al. 2024

Li et al. (2024). The genome sequence of the giant clam, Tridacna gigas (Linnaeus, 1758). Wellcome Open Research.

The page saysevery giant clam species has this partnership with algae called Symbiodiniaceae
The source saysAll species within the subfamily form a photosymbiotic partnership with Symbiodiniaceae dinoflagellates
The page saysThe genome team reports the largest individual as 137 cm long and 500 kg.
The source sayswith the largest individual measuring an impressive 137 cm in length and weighing a remarkable 500 kg
The page saysThe biggest on record weighed 500 kg and measured 137 cm in length, the figures given in the 2024 paper that sequenced its genome.
The source sayswith the largest individual measuring an impressive 137 cm in length and weighing a remarkable 500 kgNote: FAQ 1; 2024 is the genome paper's publication year (Wellcome Open Research 2024)

Source
05

Bonham 1965

Bonham (1965). Growth Rate of Giant Clam Tridacna gigas at Bikini Atoll as Revealed by Radioautography. Science.

The page saysA 1965 study of a 52 cm clam from Bikini Atoll counted bands in its shell, read them as yearly rings, and put it in its 9th year.
The source saysThe regular banding seen in the sections is interpreted as annular in nature. One annulus precedes the 1956 layer of radioactivity, two intervene in 1958, and six follow to the time of collection, so that this clam (length, 52 centimeters) was in its 9th year of life.Note: 1965 is the paper's publication year

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.