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What the sources say

Alligator GarAtractosteus spatula

Every figure, record and mechanism on the Alligator Gar profile was written from a source, and this is the working table behind it: 58 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

Collette et al. 2019

Collette et al. (2019). Atractosteus spatula. The IUCN Red List of Threatened Species 2019: e.T191024A1966892.

The page saysthe IUCN lists the species as Least Concern
The source saysLeast ConcernNote: category read from GBIF's copy of the assessment, per docs/fact-check.md

Source
02

Animal Diversity Web, University of Michigan

Atractosteus spatula (Gemfish). Animal Diversity Web, University of Michigan.

The page saysa swim bladder that can work as a lung
The source saysTheir swim bladder can function as a lung.
The page saysa vascularized swim bladder that can work as a lung
The source saysTheir swim bladder can function as a lung.

Source
03

Florida Museum of Natural History

Alligator Gar, Atractosteus spatula. Florida Museum of Natural History.

The page saystwo rows of fang-like teeth in its upper jaw
The source saystwo rows of fang-like teeth in the upper jaw
The page saysLarge, slow-moving rivers, reservoirs, oxbow lakes, bayous, and brackish bays
The source saysThe alligator gar inhabits large, slow moving rivers, reservoirs, oxbow lakes, bayous and bays, in fresh and brackish water.
The page saysfrom the Florida Panhandle across the Gulf Coastal Plain to Veracruz, Mexico
The source saysThe range of the alligator gar extends from the Florida Panhandle, through the Gulf Coastal Plain and the Mississippi River Basin extending north to the lower portions of the Ohio and the Missouri River, and ranges southwest through Texas down to Veracruz, Mexico.
The page saysMostly fish, plus blue crabs in brackish water, turtles, waterfowl, small mammals, and carrion
The source saysThe alligator gars' diet consists primarily of fish. However, brackish water populations of alligator gar are known to feed heavily on blue crabs in addition to fish such as the hardhead catfish. This gar is also known to prey on waterfowl and other birds, small mammals, turtles, and carrion.
The page saystwo rows of fang-like teeth in the upper jaw
The source saystwo rows of fang-like teeth in the upper jaw
The page saysIt is the largest of the seven living gar species
The source saysThe alligator gar is one of the largest freshwater fishes in North America and is the largest of the gar species.
The page saysthe seven living gar species
The source saysThere is only one extant family of gar, Lepisosteidae, which has seven species all located in North and Central America.
The page saysAlligator gar commonly grow to about 2 meters (6.5 feet) and over 45 kilograms (100 pounds)
The source saysAlligator gars commonly grow to a size of 6 1/2ft (2 m) and over 100 lbs. (45kg).Note: 6.5 feet is the decimal form of the quote's '6 1/2ft'
The page sayshave been reported to reach around 3 meters (10 feet)
The source sayshave been reported to grow up to 350 lbs. and around 10 ft (3m) in length
The page saysOne caught in Arkansas's St. Francis River in the 1930s weighed 159 kilograms (350 pounds)
The source saysThe largest recorded alligator gar comes from the St. Francis River, Arkansas in the 1930's, and weighed 350 lbs (159 kg).Note: 'largest recorded' left out: TPWD calls a 327-pound 2011 fish the world record
The page saysOne caught in Arkansas's St.
The source saysThe largest recorded alligator gar comes from the St. Francis River, Arkansas in the 1930's, and weighed 350 lbs (159 kg).Note: duplicate of the claim above, truncated at 'St.' so the sentence-splitter's abbreviation break still resolves to a covered claim
The page saysFemales mature around age 11 and males around age 6
The source saysfemale alligator gars reaching sexual maturity around age 11 and living to age 50. Male alligator gars mature around age 6 and live at least 26 years.Note: lifespans left out: the Florida Museum's 'living to age 50' conflicts with TPWD's 2011 fish 'probably at least 95'
The page saysAmbush Hunter, Two Rows of Teeth
The source saystwo rows of fang-like teeth in the upper jaw
The page saysGars hunt by ambush: they lie still until a fish swims by, then lunge forward, lashing the head from side to side to catch it
The source saysGars are ambush predators, primarily piscivores, they lay still in the water until an unsuspecting fish swims by, and then lunging forward and lashing the head from side to side in order to capture prey.
The page saysThe alligator gar's short, broad snout carries two rows of fang-like teeth in the upper jaw, the inner row larger than the outer
The source saysrelatively short, broad snout which has two rows of fang-like teeth in the upper jaw. The inner row of teeth in the upper jaw is palatine and larger than the outer row of teeth.
The page saysIts diet is mostly fish, but populations in brackish water (a mix of fresh and salt water) are known to feed heavily on blue crabs, and it also preys on waterfowl, turtles, small mammals and carrion
The source saysThe alligator gars' diet consists primarily of fish. However, brackish water populations of alligator gar are known to feed heavily on blue crabs in addition to fish such as the hardhead catfish. This gar is also known to prey on waterfowl and other birds, small mammals, turtles, and carrion.
The page saysDespite its size and sharp teeth, there is no documentation of an alligator gar attacking a person, though it is capable of a serious bite wound
The source saysDue to its large size and sharp teeth, the alligator gar is capable of delivering a serious bite wound to fisherman or swimmers. However, there is no documentation of attacks on man by alligator gars.
The page saysOnce a young gar reaches about a meter (3 feet), its only natural predator would be the American alligator
The source saysYoung gars are preyed upon by larger fish, but once they reach a size of about 3 feet (1 m) their only natural predator would be an American alligator
The page saysThe eggs are bright red and poisonous if eaten.
The source saysThe eggs are bright red and poisonous if eaten.
The page saysBreathing Air When Oxygen Runs Low
The source saysGars also have a highly vascularized swim bladder connected to the pharynx by a pneumatic duct. This enables them to gulp air, which aids in facultative air breathing. This allows gar to breathe when there are very low oxygen levels in the water.
The page saysLike other gars, it has a swim bladder packed with blood vessels and connected to its throat by a duct
The source saysGars also have a highly vascularized swim bladder connected to the pharynx by a pneumatic duct. This enables them to gulp air, which aids in facultative air breathing. This allows gar to breathe when there are very low oxygen levels in the water.Note: 'packed with blood vessels' for 'highly vascularized'; throat for pharynx
The page saysThis lets a gar gulp air and breathe even when the water holds very little oxygen
The source saysGars also have a highly vascularized swim bladder connected to the pharynx by a pneumatic duct. This enables them to gulp air, which aids in facultative air breathing. This allows gar to breathe when there are very low oxygen levels in the water.Note: 'lets' paraphrases 'enables' and 'allows'
The page saysIt is also the gar species most tolerant of salty water.
The source saysThe alligator gar is the most tolerant gar species of high salinity and occasionally strays into salt water.
The page saysIts range runs from the Florida Panhandle across the Gulf Coastal Plain to Veracruz, Mexico
The source saysThe range of the alligator gar extends from the Florida Panhandle, through the Gulf Coastal Plain and the Mississippi River Basin extending north to the lower portions of the Ohio and the Missouri River, and ranges southwest through Texas down to Veracruz, Mexico.
The page saysIt has suffered from overfishing, and dams, dikes and other flood control works have cost it key breeding habitat
The source saysdeclining in population everywhere due to over-fishing and the construction of dikes, dams, and other flood control devices, resulting in loss of key breeding habitatNote: 'everywhere' left out: TPWD says Texas populations are still strong
The page saysThere is no documentation of an alligator gar attacking a person.
The source saysthere is no documentation of attacks on man by alligator gars
The page saysWith its large size and sharp teeth, though, it is capable of delivering a serious bite wound to a fisherman or swimmer
The source saysDue to its large size and sharp teeth, the alligator gar is capable of delivering a serious bite wound to fisherman or swimmers
The page saysIts swim bladder, packed with blood vessels, lets gars gulp air and breathe even when the water holds very little oxygen
The source saysGars also have a highly vascularized swim bladder connected to the pharynx by a pneumatic duct. This enables them to gulp air, which aids in facultative air breathing. This allows gar to breathe when there are very low oxygen levels in the water.

Source
04

Texas Parks and Wildlife Department

Alligator Gar (Atractosteus spatula). Texas Parks and Wildlife Department.

The page saysinterlocking ganoid scales
The source saysdiamond-shaped interlocking (ganoid) scales
The page sayshistorically north to the lower Missouri and Ohio rivers
The source saysThe historic range extends north in the Mississippi River basin to the lower reaches of the Missouri and Ohio rivers.
The page saysalligator gar can live for many decades
The source saysAlligator gar can live for many decades.
The page saysThey grow very fast when young, but growth slows with age.
The source saysThey grow very fast when young, but growth slows with age.
The page saysIn general, each extra foot of length doubles a gar's age
The source saysIn general, for every additional foot the fish grows, its age doubles.
The page saysa 3-foot fish is typically about two and a half years old, and a 7-foot trophy catch might be 40
The source saysA 3-foot gar is typically about 2.5 years old; a 4-foot gar about 5, and a 7-foot trophy catch might be 40 years old.Note: dropped the 4-foot/age-5 middle example for length
The page saysA 327-pound (148-kilogram) fish caught in Mississippi in 2011 was probably at least 95 years old
The source saysThe world record, caught in Mississippi in 2011, weighed 327 pounds and was probably at least 95.Note: 148 kg is 327 lb converted; 'world record' left out as a current-state claim
The page saysIts body is wrapped in interlocking, diamond-shaped ganoid scales
The source sayslong, slender, cylindrical bodies, long snouts, and diamond-shaped interlocking (ganoid) scales
The page sayshistorically north up the Mississippi River basin to the lower Missouri and Ohio rivers
The source saysThe historic range extends north in the Mississippi River basin to the lower reaches of the Missouri and Ohio rivers.
The page saysSurveys show it declining or gone in many areas of the southeastern United States
The source saysRecent surveys indicate the species is declining or has disappeared in many areas of the southeastern United States.
The page saysTexas populations are still strong
The source saysTexas populations are still strong.

Source
05

Allison et al. 2013

Allison et al. (2013). Mechanical properties and structure of the biological multilayered material system, Atractosteus spatula scales. Acta Biomaterialia.

The page saysArmor Built in Two Layers
The source saysa thinner, stiffer and harder outer layer (indentation modulus ∼69 GPa and hardness ∼3.3 GPa) on a more compliant and thicker inner layer (indentation modulus ∼14.3 GPa and hardness ∼0.5 GPa)
The page saysTwo layers, two hardnesses
The source saysa thinner, stiffer and harder outer layer (indentation modulus ∼69 GPa and hardness ∼3.3 GPa) on a more compliant and thicker inner layer (indentation modulus ∼14.3 GPa and hardness ∼0.5 GPa)
The page saysIn lab tests, the outer layer of an alligator gar scale measured about 3.3 gigapascals of hardness, more than six times the 0.5 of the bony layer beneath
The source saysa thinner, stiffer and harder outer layer (indentation modulus ∼69 GPa and hardness ∼3.3 GPa) on a more compliant and thicker inner layer (indentation modulus ∼14.3 GPa and hardness ∼0.5 GPa)Note: ~3.3 / ~0.5 = 6.6, stated as more than six times; lab tests = microindentation tests on A. spatula scales

Source
06

Sherman et al. 2017

Sherman et al. (2017). A comparative study of piscine defense: The scales of Arapaima gigas, Latimeria chalumnae and Atractosteus spatula. Journal of the Mechanical Behavior of Biomedical Materials.

The page saysInterlocking ganoid scale armor with a hard outer layer over a tough bony base
The source saysinflexible articulating ganoid scales made of a hard and highly mineralized enamel-like outer surface and a tough dentine-like bony baseNote: 'articulating' (jointed) scales; TPWD calls them interlocking
The page saysEach scale has a hard, enamel-like outer layer over a tough, dentine-like bony base
The source saysa hard and highly mineralized enamel-like outer surface and a tough dentine-like bony base
The page saysTogether, the layers resist powerful bites from alligators and from other alligator gar
The source sayswhich resist powerful bite forces of self-predation and attack by alligatorsNote: 'self-predation' is the paper's term for an attack by another fish of the same species
The page saysJointed ganoid scales, each with a hard, highly mineralized, enamel-like outer layer over a tough, dentine-like bony base
The source saysinflexible articulating ganoid scales made of a hard and highly mineralized enamel-like outer surface and a tough dentine-like bony base
The page saysThe scales resist powerful bites, including attacks by alligators and by other alligator gar
The source sayswhich resist powerful bite forces of self-predation and attack by alligators

Source
07

Sherman et al. 2016

Sherman et al. (2016). Microstructural and geometric influences in the protective scales of Atractosteus spatula. Journal of The Royal Society Interface.

The page saysDescribed as a 100-million-year-old living fossil
The source sayshas been described as a living fossil (having existed for 100 Myr)
The page saysA Giant Living Fossil
The source sayshas been described as a living fossil (having existed for 100 Myr)
The page saysliving fossil that has existed for around 100 million years
The source sayshas been described as a living fossil (having existed for 100 Myr)
The page sayskeeping traits from its early ancestors, including the ability to breathe air
The source saysretaining morphological characteristics of early ancestors such as the ability to breathe air and survive above water for hours
The page saysTiny saw-tooth ridges along the boundary between the two layers steer cracks away from that boundary, which is naturally weak
The source sayssaw-tooth ridges along the interface between the two scale layers which direct cracks away from the intrinsically weak interfaceNote: 'Tiny': the abstract lists them among its microstructural features
The page saysthe alligator gar can survive out of water for hours
The source saysthe ability to breathe air and survive above water for hours
The page saysYes, for hours.
The source saysthe ability to breathe air and survive above water for hours
The page saysScientists describe the ability to breathe air and survive out of water for hours as traits it kept from its early ancestors
The source saysretaining morphological characteristics of early ancestors such as the ability to breathe air and survive above water for hours

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.