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What the sources say

American AlligatorAlligator mississippiensis

Every figure, record and mechanism on the American Alligator 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

Erickson et al. 2012

Erickson et al. (2012). Insights into the Ecology and Evolutionary Success of Crocodilians Revealed through Bite-Force and Tooth-Pressure Experimentation. PLoS ONE.

The page saysA 9,452-Newton Bite
The source saysAlligator mississippiensis 15 0.69 142 47–297 285 213–372 5117 2442–9452Note: blockquote lead-in; the top of the measured range, not rounded
The page saysA 2012 study measured bite forces in adults of all 23 living crocodilian species and found these reptiles generate the highest bite forces and tooth pressures known for any living animals
The source saysWe measured adult bite forces and tooth pressures in all 23 extant crocodilian species and analyzed the results in ecological and phylogenetic contexts. We demonstrate that these reptiles generate the highest bite forces and tooth pressures known for any living animals.Note: 2012 is the reference's own year
The page saysThe 15 American alligators tested bit with up to 9,452 newtons at a back tooth, about 2,125 pounds of force
The source saysAlligator mississippiensis 15 0.69 142 47–297 285 213–372 5117 2442–9452Note: Table 1 row: N = 15 specimens; RMBF (Range of Molariform Bite Forces, N) = 2442-9452. The molariform tooth is the prominent upper tooth 'at the maxilla convexity nearer the back of the jaws'. 9452 N / 4.44822 = 2,125 pounds of force. MBF 5117 is a power-law-modelled taxon representative value, not a mean, so it is not quoted
The page saysA 2012 study that measured bite forces in adults of all 23 living crocodilian species found they generate the highest bite forces and tooth pressures known for any living animals
The source saysWe measured adult bite forces and tooth pressures in all 23 extant crocodilian species and analyzed the results in ecological and phylogenetic contexts. We demonstrate that these reptiles generate the highest bite forces and tooth pressures known for any living animals.Note: faq 1; 2012 is the reference's own year
The page saysThe 15 American alligators tested bit with up to 9,452 newtons at a back tooth, about 2,125 pounds of force
The source saysAlligator mississippiensis 15 0.69 142 47–297 285 213–372 5117 2442–9452Note: faq 1; Table 1 row: N = 15 specimens; RMBF (Range of Molariform Bite Forces, N) = 2442-9452. The molariform tooth is the prominent upper tooth 'at the maxilla convexity nearer the back of the jaws'. 9452 N / 4.44822 = 2,125 pounds of force. MBF 5117 is a power-law-modelled taxon representative value, not a mean, so it is not quoted
The page saysfor jaws that bit with up to 9,452 newtons when 15 adults were tested
The source saysAlligator mississippiensis 15 0.69 142 47–297 285 213–372 5117 2442–9452Note: vibe.reason (#391): n=15, bite force range 2442-9452 N

Source
02

Green et al. 2014

Green et al. (2014). Three crocodilian genomes reveal ancestral patterns of evolution among archosaurs. Science.

The page saysA 2014 study of three crocodilian genomes, the American alligator's among them, found an exceptionally slow rate of genome evolution within crocodilians at every level it measured
The source sayswe generated draft genomes of three crocodilians: Alligator mississippiensis (the American alligator), ... We observed an exceptionally slow rate of genome evolution within crocodilians at all levelsNote: 2014 is the reference's own year
The page saysCompared with birds and turtles, the results suggested that the shared ancestor of all these groups also had slow genome evolution, and that the faster change seen in birds came later
The source saysWhen placed within the context of related taxa including birds and turtles, this suggests that the common ancestor of all of these taxa also exhibited slow genome evolution and that the comparatively rapid evolution is derived in birds.Note: 'came later, in the bird line' paraphrases 'the comparatively rapid evolution is derived in birds'

Source
03

Elsey, Woodward & Balaguera-Reina 2019

Elsey, Woodward & Balaguera-Reina (2019). Alligator mississippiensis. The IUCN Red List of Threatened Species 2019: e.T46583A3009637.

The page saysLeast Concern
The source saysIUCN Red List Category Least Concern (LC) Alligator mississippiensisNote: stats.conservationStatus; GBIF's copy of the Red List; assessed 2018, published 2019

Source
04

Smithsonian's National Zoo and Conservation Biology Institute

American alligator. Smithsonian's National Zoo and Conservation Biology Institute.

The page saysAn armored reptile
The source saysThe American alligator is a large crocodilian with an armored bodyNote: tagline; 'reptile' from the same page: 'This reptile nearly went extinct'
The page sayswith jaws that can crack a turtle shell
The source saysvery strong jaws that can crack a turtle shell
The page saysa mouth that can go through 3,000 teeth in a lifetime
The source saysAn alligator can go through 3,000 teeth in a lifetime.
The page saysfrom coastal North Carolina to central Texas
The source saysranging from the northern coasts of North Carolina to Lake Worth in central TexasNote: stats.habitat
The page saysJaws strong enough to crack a turtle shell
The source saysThey have very strong jaws that can crack a turtle shell.Note: stats.superpower
The page sayslive mostly in the freshwater rivers, swamps, marshes, and lakes of the southeastern United States, from the coast of North Carolina to central Texas
The source saysThe American alligator is found across the southeastern United States, ranging from the northern coasts of North Carolina to Lake Worth in central Texas. Alligators are usually found in freshwater, slow-moving rivers. They also live in swamps, marshes and lakes.
The page saysAdult females average 8.2 feet (2.6 meters) long
The source saysThe average adult size for a female is 8.2 feet (2.6 meters)
The page saysadult males average 11.2 feet (3.4 meters)
The source saysthe average size for a male is 11.2 feet (3.4 meters)
The page saysExceptionally large males can near half a ton, about 1,000 pounds (454 kilograms)
The source saysExceptionally large males can reach a weight of nearly half a ton or 1,000 pounds (454 kilograms).
The page saysWild alligators live about 50 years
The source saysAmerican alligators live about 50 years in the wild.Note: current Smithsonian page; ADW's older student account gives 20-30 years wild, so the current page wins
The page saysThe skin on an alligator's back is armored with embedded bony plates called osteoderms, or scutes
The source saysThe skin on their back is armored with embedded bony plates called osteoderms or scutes.
The page saysThe American Alligator (Alligator mississippiensis) has 74 to 80 teeth in its mouth at a time
The source saysAlligators have between 74 and 80 teeth in their mouth at a time.
The page saysAs they wear down they are replaced, and one alligator can go through 3,000 teeth in a lifetime
The source saysAs they wear down, they are replaced. An alligator can go through 3,000 teeth in a lifetime.
The page saysThe large fourth tooth in its lower jaw fits into a socket in the upper jaw and is hidden when the mouth is closed. That does not happen in crocodiles, which makes the teeth an easy way to tell the two apart
The source saysIt's easy to distinguish an alligator from a crocodile by the teeth. The large, fourth tooth in the lower jaw of an alligator fits into a socket in the upper jaw and is not visible when the mouth is closed. This does not happen in crocodiles.
The page saysTheir very strong jaws can crack a turtle shell
The source saysThey have very strong jaws that can crack a turtle shell.
The page saysSmall prey gets swallowed whole. Very large prey gets bitten, and then the alligator spins on the long axis of its body to tear off pieces small enough to swallow
The source saysThey swallow small prey whole. If the prey is large, they shake it apart into smaller, manageable pieces. If it is very large, they will bite it, then spin on the long axis of their bodies to tear off easily swallowed pieces.
The page saysIts long, rounded snout has upward-facing nostrils at the end, which allows it to breathe while the rest of its body is underwater
The source saysAlligators have a long, rounded snout that has upward facing nostrils at the end; this allows breathing to occur while the rest of the body is underwater.
The page saysThe temperature of the nest sets a hatchling's sex
The source saysThe sex of the juveniles is determined by the temperature of the nest.
The page saysTemperatures of 31°C (87.8°F) or below produce females
The source saysTemperatures of 31? C (87.8? F) or below produce females.Note: Only the female threshold is used: this page also says 32 C gives 75% males but 32.5 C and above mostly females, while NPS (90-93 F males) and ADW (>=33 C males) disagree on the male range. All three agree that 31 C or below gives females.
The page saysAlligators do not hibernate, but they go through periods of dormancy when the weather becomes cold
The source sayseven though they do not hibernate, they undergo periods of dormancy when the weather becomes cold
The page saysThey dig a depression called a "gator hole" along a waterway to use when the seasonal temperature falls
The source saysThey excavate a depression called a "gator hole" along a waterway to be used when the seasonal temperature falls.
The page saysThey do not hibernate, but they go through periods of dormancy when the weather becomes cold
The source sayseven though they do not hibernate, they undergo periods of dormancy when the weather becomes coldNote: faq 2
The page saysAlligators dig a depression called a "gator hole" along a waterway to use when the seasonal temperature falls
The source saysThey excavate a depression called a "gator hole" along a waterway to be used when the seasonal temperature falls.Note: faq 2
The page saysWhere the water level changes, they dig into hollows in the mud that fill with water. These tunnels can run as long as 65 feet (20 meters) and protect them during extreme hot or cold weather
The source saysIn areas where the water level fluctuates, alligators dig themselves into hollows in the mud, which fill with water. These tunnels can be as long as 65 feet (20 m) and provide protection during extreme hot or cold weather.Note: faq 2
The page saysThe temperature of the nest
The source saysThe sex of the juveniles is determined by the temperature of the nest.Note: faq 3
The page saysTemperatures of 31 degrees Celsius (87.8 degrees Fahrenheit) or below produce females, while a slightly warmer nest can produce mostly males
The source saysTemperatures of 31? C (87.8? F) or below produce females. A temperature of 32? C (89.6? F) produces 75 percent malesNote: 'slightly warmer' = 32 C against 31 C; 'can' because the same page says 32.5 C and above are mostly females
The page saysLook at the large fourth tooth in the lower jaw. In an alligator it fits into a socket in the upper jaw and is hidden when the mouth is closed. That does not happen in crocodiles
The source saysThe large, fourth tooth in the lower jaw of an alligator fits into a socket in the upper jaw and is not visible when the mouth is closed. This does not happen in crocodiles.Note: faq 4

Source
05

Everglades National Park, National Park Service

American Alligator: Species Profile. Everglades National Park, National Park Service.

The page saysFreshwater swamps, marshes, rivers, and lakes
The source saysAlligators primarily inhabit freshwater swamps and marshes and can also be found in rivers, lakes, and smaller bodies of water.Note: stats.habitat
The page saysTypically fish, turtles, small mammals, birds, and reptiles, including small alligators
The source saysThe adult diet typically consists of fish, turtles, small mammals, birds, and reptiles, including small alligators.Note: stats.diet
The page sayssome adult males occasionally reach 13 to 15 feet
The source saysAdult male alligators occasionally reach 13 to 15 feet in length.
The page saysAlligators can tolerate a reasonable degree of salinity for short periods, even though, unlike crocodiles, they lack salt-secreting glands
The source saysThey can tolerate a reasonable degree of salinity for short periods of time and are occasionally found in brackish water around mangrove swamps even though they lack the salt-secreting glands present in crocodiles.
The page saysAdults typically eat fish, turtles, small mammals, birds, and reptiles, including small alligators
The source saysThe adult diet typically consists of fish, turtles, small mammals, birds, and reptiles, including small alligators.
The page saysburrow out dens for shelter when winter temperatures drop
The source saysDens are burrowed out and used for shelter and aestivation when winter temperatures fall
The page saysEven outside their dens, they can tolerate limited periods of freezing conditions
The source saysEven outside their dens they can tolerate limited periods of freezing conditions.

Source
06

Animal Diversity Web, University of Michigan

Alligator mississippiensis. Animal Diversity Web, University of Michigan.

The page saysa diet study in Texas found feral hogs among their prey
The source saysSaalfeld et al.(2011) conducted a diet study in Texas, ... A few examples of animals consumed are ... Sus scrofa (feral hog).
The page saysSense organs in an alligator's jaws and scales, called integumentary sense organs, help it sense movements in the water, tell it when prey is touching its teeth, and identify what it is holding in its jaws
The source saysIntegumentary sense organs (ISO) are features of an alligator to help it perceive its environment. These ISOs can be found in the jaws or scales of the alligator. The ISOs help the American alligator sense movements in the water, tell it when prey is in contact with the teeth, and help identify what item it has in its jaw at a certain time.
The page saysweightKg: 150
The source saysthe average weight is 150 kgNote: battleStats (#391); Erickson 2012's 15 adults averaged 142 kg

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.