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What the sources say

Tiger SharkGaleocerdo cuvier

Every figure, record and mechanism on the Tiger Shark profile was written from a source, and this is the working table behind it: 54 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

Animal Diversity Web, University of Michigan

Galeocerdo cuvier (tiger shark). Animal Diversity Web, University of Michigan.

The page saysserrated teeth that can pierce sea turtle shells
The source saysSerrated teeth give this species the ability to penetrate the shells of sea turtles.Note: 'pierce' paraphrases 'penetrate'
The page sayscan pierce sea turtle shells
The source saysSerrated teeth give this species the ability to penetrate the shells of sea turtles.
The page saysthey can pierce the shells of sea turtles
The source saysSerrated teeth give this species the ability to penetrate the shells of sea turtles.
The page saysA tiger shark most likely relies on stealth rather than strength and speed to catch prey, and its camouflage lets it get within striking range.
The source saysThis species most likely relies on stealth rather than strength and speed to catch prey. They are well camouflaged, allowing them to get within striking range of prey.Note: current FL page agrees: 'a highly effective ambush predator that deploys short bursts of speed to secure its prey'
The page saysIf prey flees, it may back off instead of chasing at high speed, but it can manage a short burst of speed once prey is within range.
The source saysIf prey flee, tiger sharks may back off, not taking part in high-speed pursuits. However, tiger sharks are capable of short bursts of speed once their prey are within range.Note: 'instead of chasing at high speed' paraphrases 'not taking part in high-speed pursuits'
The page saysSensing organs called ampullae of Lorenzini, on the end of its snout, detect electromagnetic signals given off by fish.
The source saysSensing organs called Ampullae of Lorenzini, located on the end of their nose ... While hunting, tiger sharks uses this ability to detect electromagnetic signals given off by fish.
The page saysTiger sharks are solitary except during mating season or while feeding together on a large carcass.
The source saysTiger sharks are a nocturnal predators and are solitary except during the mating seasons or while communally feeding on large carcasses.Note: current FL page agrees: 'sometimes seen in groups, but this is probably driven by food availability rather than social behavior'
The page saysAt those feeds, larger sharks eat first in a loose pecking order, and violence is minimal.
The source saystiger sharks have a loose social hierarchy where larger sharks feed first ... Violence is minimal during these scavenging feasts.
The page saysNot at full strength. Tiger sharks are born with tiger-like stripes on their back
The source saysThey are born with tiger-like stripes on their back
The page saysthe stripes fade as they grow older
The source saysJuveniles have tiger-like stripes, which fade as they grow older.

Source
02

Florida Museum of Natural History, Discover Fishes

Galeocerdo cuvier. Florida Museum of Natural History, Discover Fishes.

The page saysA shark with a reputation for eating almost anything
The source saysthe tiger shark has a reputation as an animal that will eat almost anything
The page saysa habit of hunting at night
The source saysTiger sharks are solitary hunters that feed primarily at night as the shark moves further inshore and closer to the surface.
The page saysDeadly
The source sayssecond only to the white shark ( Carcharodon carcharias ) in terms of the number of reported attacks on humans ... one of the three species most commonly implicated in shark attacks and fatalitiesNote: dangerLevel left as the writer set it; the source supports a fatal-attack record
The page saysTropical and temperate seas worldwide except the Mediterranean
The source saysThe tiger shark is found throughout the world's temperate and tropical waters, with the exception of the Mediterranean Sea.
The page saysgenerally preferring murky coastal waters; common in river estuaries and harbors, and found around the lagoons and coral atolls of oceanic islands
The source saysgenerally prefers murky waters in coastal areas. It is commonly found in river estuaries, harbors, and other inlets ... Tiger sharks also occur in shallow areas around large island chains, including the lagoons and coral atolls found on the coasts of oceanic islands
The page saysSea turtles, rays, other sharks, bony fish, sea birds, dolphins, squid, crustaceans and carrion
The source saysPreferred prey varies depending upon geographical region but commonly includes sea turtles, rays, other sharks, bony fishes, sea birds, dolphins, squid, various crustaceans and carrion.
The page saysplus garbage, often found in sharks caught in harbors
The source saysGarbage and refuse is often recovered from the stomachs of sharks caught in harbors and river inlets, where it is commonly dumped into the water.
The page saysDeeply notched, serrated teeth
The source saysThe jaws house large teeth with curved cusps and finely serrated edges. Each tooth has a deep notch on the outer margin lined with numerous cusplets.
The page sayswith a saw-like shake of the head, tear chunks from much larger animals
The source saysThe tiger shark's highly serrated teeth combined with the saw-like action from shaking the head back and forth allows it to tear chunks from much larger marine animals.
The page saysThe tiger shark has a reputation for eating almost anything.
The source saysthe tiger shark has a reputation as an animal that will eat almost anything
The page saysOne large female caught in the Red Sea held two empty cans, a plastic bottle, two burlap sacks, a squid, and a 20 cm fish.
The source saysOne large female caught off the north end of the Gulf of Aqaba in the Red Sea contained two empty cans, a plastic bottle, two burlap sacks, a squid, and a 20 cm (8 in) fish.
The page saysGarbage dumped into harbors and river inlets often turns up in the stomachs of sharks caught there.
The source saysGarbage and refuse is often recovered from the stomachs of sharks caught in harbors and river inlets, where it is commonly dumped into the water.
The page saysIts usual prey, which varies by region, includes sea turtles, rays, other sharks, bony fish, sea birds, dolphins, squid, crustaceans and carrion.
The source saysPreferred prey varies depending upon geographical region but commonly includes sea turtles, rays, other sharks, bony fishes, sea birds, dolphins, squid, various crustaceans and carrion.
The page saysTiger sharks commonly reach 3.25 to 4.25 m long and weigh 385 to 635 kg.
The source saysthe tiger shark commonly reaches a length of 325-425 cm (10-14 ft) and weighs over 385-635 kg (850-1400 lbs).Note: 325-425 cm = 3.25-4.25 m. ADW agrees: 'Adults range from 3.25 to 4.25 m in length ... Adult tiger sharks typically weigh 385 to 635 kg'
The page saysThe largest reach over 5.5 m and are estimated to weigh over 900 kg.
The source saysThe largest specimens attain lengths of over 5.5 m (18 ft) and are estimated to weigh over 900 kg (2000 lbs).Note: 'top' = attain over
The page saysEach tooth has curved cusps, finely serrated edges and a deep notch on the outer margin, and teeth in the upper and lower jaws are similarly shaped.
The source saysThe jaws house large teeth with curved cusps and finely serrated edges. Each tooth has a deep notch on the outer margin lined with numerous cusplets. Teeth are similarly shaped in both upper and lower jaws
The page saysCombined with a saw-like shake of the head, those teeth tear chunks from much larger animals
The source saysThe tiger shark's highly serrated teeth combined with the saw-like action from shaking the head back and forth allows it to tear chunks from much larger marine animals.
The page saysIt feeds mainly at night, moving further inshore and closer to the surface.
The source saysTiger sharks are solitary hunters that feed primarily at night as the shark moves further inshore and closer to the surface.
The page saysTiger sharks live in tropical and temperate waters around the world, except the Mediterranean Sea.
The source saysThe tiger shark is found throughout the world's temperate and tropical waters, with the exception of the Mediterranean Sea.Note: replaces ADW's older 'subtropical and tropical waters' range
The page saysThey are commonly found in river estuaries, harbors and other inlets, and around the lagoons and coral atolls of oceanic islands.
The source saysIt is commonly found in river estuaries, harbors, and other inlets ... Tiger sharks also occur in shallow areas around large island chains, including the lagoons and coral atolls found on the coasts of oceanic islandsNote: 'commonly' governs the inlets clause only, as in the source
The page saysOften seen at the surface, they have been reported at depths of 350 m.
The source saysIt is often seen at the surface but has been reported at depths of 350 m (1085 ft)
The page saysThey move into temperate waters in warmer months and return to the tropics for winter.
The source saysThey move into temperate waters from the tropics in warmer months and return to the tropics during the winter.
The page saysTiger sharks have a reputation for eating almost anything.
The source saysthe tiger shark has a reputation as an animal that will eat almost anything
The page saysOne large female caught in the Red Sea held two empty cans, a plastic bottle, two burlap sacks, a squid, and a 20 cm fish
The source saysOne large female caught off the north end of the Gulf of Aqaba in the Red Sea contained two empty cans, a plastic bottle, two burlap sacks, a squid, and a 20 cm (8 in) fish.
The page saysgarbage dumped into harbors and river inlets often turns up in the stomachs of sharks caught there
The source saysGarbage and refuse is often recovered from the stomachs of sharks caught in harbors and river inlets, where it is commonly dumped into the water.
The page saysTheir usual prey, which varies by region, includes sea turtles, rays, other sharks, bony fish, sea birds, dolphins, squid, crustaceans and carrion.
The source saysPreferred prey varies depending upon geographical region but commonly includes sea turtles, rays, other sharks, bony fishes, sea birds, dolphins, squid, various crustaceans and carrion.
The page saysfor serrated teeth that saw chunks from much larger animals with a back-and-forth shake of the head
The source saysThe tiger shark's highly serrated teeth combined with the saw-like action from shaking the head back and forth allows it to tear chunks from much larger marine animals.Note: vibe.reason (#391)
The page saysweightKg: 510
The source saysthe tiger shark commonly reaches a length of 325-425 cm (10-14 ft) and weighs over 385-635 kg (850-1400 lbs).Note: battleStats; midpoint of the typical range (#391)

Source
03

Emmons et al. 2021

Emmons et al. (2021). Age and growth of tiger shark (Galeocerdo cuvier) from Western Australia. Marine and Freshwater Research.

The page saysVertebrae from tiger sharks caught off Western Australia were aged up to 31 years old in females and 21 in males.
The source saysVertebrae samples were taken from 124 tiger sharks ... caught in Western Australia (WA) from 1994 to 1998 ... Males (n = 38) were found to have an age range of 3–21 years ... females (n = 60) had an age range of 2–31 yearsNote: sample ages, not a lifespan; ADW's older 27/50-year wild lifespan is not used

Source
04

Ferreira & Simpfendorfer 2019

Ferreira & Simpfendorfer (2019). Galeocerdo cuvier. The IUCN Red List of Threatened Species 2019: e.T39378A2913541.

The page saysNear Threatened
The source saysIUCN Red List category: Near Threatened (NT).
The page saysThe IUCN lists the tiger shark as Near Threatened.
The source saysIUCN Red List category: Near Threatened (NT).
The page saysWorldwide, the IUCN Red List classifies the tiger shark as Near Threatened.
The source saysIUCN Red List category: Near Threatened (NT).

Source
05

Enax et al. 2012

Enax et al. (2012). Structure, composition, and mechanical properties of shark teeth. Journal of Structural Biology.

The page saysLab tests on tiger shark and shortfin mako teeth found the mineral in them is fluoroapatite
The source saysThe teeth of two different shark species (Isurus oxyrinchus and Galeocerdo cuvier) ... The inorganic part of shark teeth consisted of fluoroapatiteNote: Isurus oxyrinchus is the shortfin mako (Isurus is its genus as the paper spells it); the paper studied only these two species, so the page names both
The page saysthe hard outer layer is about six times harder than the dentin beneath it
The source saysNanoindentation and Vicker's microhardness tests showed that the enameloid of the shark teeth was approximately six times harder than the dentinNote: enameloid = the hard outer layer
The page saysThe same study found that each tooth's job, tearing for the mako and cutting for the tiger shark, is set by its shape rather than its chemistry.
The source saysthe different biological functions of the shark teeth ("tearing" for Isurus and "cutting" for Galeocerdo) are controlled by the different geometry and not by the chemical or crystallographic composition.Note: Isurus oxyrinchus is the shortfin mako (Isurus is its genus as the paper spells it); the paper studied only these two species, so the page names both
The page saysBut the job each tooth does, tearing for the mako and cutting for the tiger shark, is set by its shape
The source saysthe different biological functions of the shark teeth ("tearing" for Isurus and "cutting" for Galeocerdo) are controlled by the different geometry and not by the chemical or crystallographic composition.Note: answer lead; the FAQ's own study says geometry sets the cutting function
The page saysLab tests on tiger shark and shortfin mako teeth found the hard outer layer is about six times harder than the dentin beneath it
The source saysThe teeth of two different shark species (Isurus oxyrinchus and Galeocerdo cuvier) ... the enameloid of the shark teeth was approximately six times harder than the dentinNote: Isurus oxyrinchus is the shortfin mako (Isurus is its genus as the paper spells it); the paper studied only these two species, so the page names both

Source
06

Meyer et al. 2014

Meyer et al. (2014). Growth and Maximum Size of Tiger Sharks (Galeocerdo cuvier) in Hawaii. PLoS ONE.

The page saysIn a Hawaii tagging program, sharks over 450 cm long were very rare: just 2 of 420 captured.
The source saysindividuals larger than 450 cm TL (∼347 cm PCL) were very rare, accounting for only 2 of 420 (0.005%) sharks capturedNote: the 420 are the program's tagged sharks: 'to date 420 tiger sharks have been tagged and 50 recaptured'

Source
07

Roff et al. 2018

Roff et al. (2018). Decline of coastal apex shark populations over the past half century. Communications Biology.

The page saysQueensland, Australia, has run shark-control nets and baited drumlines since 1962, and the program grew to span 1,760 km of coast.
The source saysThe QSCP has been operating since 1962 using a system of mesh nets and baited drumlines ... The programme started in Cairns in 1962, and has since expanded to 11 regions in Queensland, spanning tropical and sub-tropical coastal ecosystems across 1760 km of the eastern Australian coastlineNote: 'off its beaches': 'employs a series of baited drumlines and mesh nets adjacent to coastal beaches'; 'grew to span' = 'has since expanded to ... spanning', past tense because the paper dates from 2018
The page saysTiger shark catch rates there were relatively stable until the early 1990s, then fell 74% over the next 25 years.
The source sayscatch rates of tiger sharks were relatively stable between the early 1960s and early 1990s, prior to a 74% decline in CPUE over the past 25 years
The page saysIn Queensland, Australia, yes.
The source sayscatch rates of tiger sharks were relatively stable between the early 1960s and early 1990s, prior to a 74% decline in CPUE over the past 25 years
The page saysCatch rates of tiger sharks in the state's shark-control nets and drumlines stayed relatively stable from the early 1960s to the early 1990s, then dropped 74% over the following 25 years.
The source sayscatch rates of tiger sharks were relatively stable between the early 1960s and early 1990s, prior to a 74% decline in CPUE over the past 25 years ... Coinciding with ongoing declines in numbers of tiger sharks in nets and drumlines

Source
08

Yopak, Lisney & Collin 2014

Yopak, Lisney & Collin (2014). Not all sharks are "swimming noses": variation in olfactory bulb size in cartilaginous fishes. Brain Structure and Function.

The page saysA study of 58 species of sharks, rays and their relatives measured the olfactory bulbs, the part of the brain that receives signals from the smell nerve.
The source saysexamining interspecific variation in the size of the olfactory bulbs (OB), the region of the brain that receives the primary sensory projections from the olfactory nerve, in 58 species of cartilaginous fishes.Note: cartilaginous fishes = sharks, rays and their relatives (chimaeras)
The page saysRelative to the rest of the brain, the largest bulbs belonged to open-water sharks, especially migratory species such as the great white and the tiger shark.
The source saysthe OBs maintain a substantial level of allometric independence from the rest of the brain ... The relatively largest OBs were found in pelagic-coastal/oceanic sharks, especially migratory species such as Carcharodon carcharias and Galeocerdo cuvier.Note: open-water = pelagic-coastal/oceanic; Carcharodon carcharias = great white

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.