image of shark fins that says meet the sharks

Sharks, rays, and skates are everywhere!

Their diverse body shapes and feeding styles help them thrive all over Earth, from arctic waters to coral reefs and from the deep sea to freshwater rivers. 

There are many different groups of these fabulous fishes, and scientists are still finding new species. Despite their fierce reputation, almost all are harmless to humans. In fact, humans pose a bigger threat to sharks, through climate change, pollution, and fishing. About half of all sharks are killed as bycatch in nets and fishing lines meant for other species.

Wanna know more about a fish? Click on it!

NOTE: PHOTOS ON THIS PAGE ARE NOT TO SCALE

JUMP TO: dogfish sharks | carpet sharks | angel sharks | mackerel sharks | bullhead sharks | sawsharks | bramble sharks | cow & frill sharks | skates | stingrays | electric rays | guitarfishes & sawfishes | chimaeras | extinct

GROUND SHARKS

The ground sharks include species as different as hammerheads, fluorescent catsharks, and powerful tiger sharks. It is the largest order of sharks.

Number of living species: more than 292 

image of shark with eyes that extend out of their head

Smooth hammerhead

Smooth hammerhead
 Sphyrna zygaena
 Maximum Length: 16.5 feet (5 meters)

hammerhead swimming towards camera trailing many bubbles

Wide head contains electroreceptors that scan seafloor for stingrays, its preferred prey; wide-set eyes provide excellent 3D vision

WHERE: Tropical and temperate coastal waters 65–656 feet (20–200 meters) deep

blue map with magenta highlights where smooth hammerhead sharks live

EATS: Skates, rays, sharks, and other fishes; crustaceans; squids and octopuses; dolphins; sea snakes

CONSERVATION STATUS: Vulnerable

THREATS: Bycatch, finning; very fragile and rarely survives capture even if released

ECO-FACT: Fast reproduction, gives live birth to 20-50 pups after 10-11 month gestation

bull shark front view

Bull Shark

Bull shark
 Carcharhinus leucas
 Maximum Length: 13 feet (4 meters)

photo of a model of a grey shark swimming towards camera

Can live in freshwater; has been found over 1,800 miles (3,000 km) up-river in both the Amazon and the Mississippi

WHERE: Coastal waters around the world, including rivers near people

bull-map

EATS: Fishes, dolphins, sea birds, sea turtles, other sharks

CONSERVATION STATUS: Vulnerable

THREATS: Habitat degradation and accidental capture

ECO-FACT: Hunts by smell, not vision; sometimes attacks humans

blue shark

Blue shark

Blue shark
 Prionace glauca 
 Maximum Length: 13 feet (4 meters)

moving image of blue shark swimming

Migrates across the Atlantic and Pacific oceans; sometimes works in groups to herd fish for easier feeding

WHERE: Globally widespread in temperate and tropical waters

blue map with magenta highlights where blue sharks live

EATS: Squids, fishes, small sharks, crustaceans, sea birds, carrion

CONSERVATION STATUS: Near Threatened

THREATS: Frequently caught as bycatch and kept for fins, animal feed, and leather

ECO-FACT: About 10-20 million killed each year in commercial fisheries

slim shark with spots

 

Swell shark

Swell shark
  Cephaloscyllium ventriosum
  Maximum Length: 3.6 feet (1.1 meters)

close-up of swell shark swelled up into a rock

Balloons in size by swallowing water, making it harder for predators to bite or pull it out of hiding spaces; emits green biofluorescent light

WHERE: Eastern coastal Pacific waters, less than 1,500 feet (450 meters) deep  

blue map with magenta highlights where swell sharks live

EATS: Small fishes, crustaceans, other invertebrates 

THREATS: Its rocky kelp habitat deters trawling, so only occasionally caught as bycatch

ECO-FACT: Rests in caves and crevices during the day, often in groups; eggs take 7–10 months to hatch

slim blue shark with grey tiger stripes

Tiger shark

Tiger shark
Galeocerdo cuvier
 Maximum Length: 24.5 feet (7.5 meters)

tiger shark swimming past

Can smell prey from great distances and may map environment by scent; second to great white in attacks on humans, but more deadly because it eats everything it bites

WHERE: Temperate and tropical waters worldwide, usually near shore

blue map with magenta highlights where tiger sharks live

EATS: Fishes, turtles, sea mammals, birds, trash

CONSERVATION STATUS: Near Threatened

THREATS: Bycatch, finning, recreational fishing, shark control programs

ECO-FACT: Live birth once every three years; litters of 10-82 pups; prevents dugongs and sea turtles from over-exploiting sea grass habitats

DOGFISH SHARKS

Many species of dogfish sharks mostly live in the deep sea and are harmless to humans. They range in size from small bioluminescent lantern sharks to large, slow-moving sleeper sharks.

Number of living species: more than 137

Spiny dogfish

Spiny dogfish

Spiny dogfish
Squalus acanthias
Maximum Length: 4 feet (1.2 meters)

image of long grey shark swimming towards camera

Aggressively hunts small fishes in packs, like dogs; has a defensive spine on each dorsal fin

WHERE: Worldwide in warm temperate waters to depths of about 3,000 feet (900 meters)

map of world indicating where spiny dogfish live

EATS: Mostly small schooling fishes as well as squids, octopuses and crustaceans

CONSERVATION STATUS: Vulnerable

THREATS: Intensive fishing, habitat loss, loss of prey species

ECO-FACT: Gestation lasts 24 months. Their population crashed because they swim in groups and are easily fished. They are now protected in Europe.

Cookiecutter shark

Cookiecutter shark

Cookiecutter shark
Isistius brasiliensis
Maximum Length: 22 inches (56 centimeters)

image of a cookie cutter shark teeth

 Saw-like teeth cut out circular chunks of flesh from larger prey; glowing spots disguise it as a smaller fish

WHERE: Tropical waters up to 11,500 feet (3,500 meters) deep

map of world indicating where cookiecutter sharks live

EATS: Cuts pieces from large fishes, squids, whales, dolphins, seals

THREATS: Occasional bycatch from oceanic trawlers

ECO-FACT: Migrates vertically two miles (3 km) up and down every day; its deep-sea habitat and small size protect against overfishing 

American pocket shark

American pocket shark

American pocket shark
Mollisquama mississippiensis
Juvenile Length: 5.5 inches (14 centimeters)

a American pocket shark near a ROV arm

First published description in 2019; thought to emit glowing liquid from pocket-like glands

WHERE: Deep water in Gulf of Mexico

map of Central America indicating where American pocket sharks live

EATS: Unknown

THREATS: Unknown; there are no fisheries near where the specimen was collected

ECO-FACT: Only two specimens have ever been found, each representing a different species

Greenland shark

Greenland shark

Greenland shark
Somniosus microcephalus
Maximum Length: 21 feet (6.4 meters)

Greenland shark slowly swimming in the depths

 The longest-living vertebrate known; may live more than 500 years and may not reach sexual maturity until age 150

WHERE: Cold water, primarily around Greenland from Europe to North America

map of north pole indicating where greenland sharks live

EATS: Fishes, marine mammals and carrion, including polar bears, moose and reindeer

CONSERVATION STATUS: Vulnerable

THREATS: Historically targeted and taken in large numbers for their liver oil in Norway, Iceland and Greenland; currently taken as bycatch

ECO-FACT: Liver contains about 30 gallons (115 liters) of oil; fished for this oil until the 1960s

CARPET SHARKS

Carpet sharks get their name from the fancy patterns on the skin of many species. The patterns help many of them hide in the reefs or tropical seas where they live.

Number of living species: more than 45

Spotted Wobbegong

Tasselled wobbegong

Tasselled wobbegong
Eucrossorhinus dasypogon
Maximum Length: 4.1 feet (1.25 meters)

tasselled wobbegong hiding among rocks

Patterned skin and tassels help it blend into reefs, concealing it from its prey; hunts at night, and hides during the day; bioflourescent

WHERE: Tropical coral reefs of northern Australia and Papua New Guinea

map of Australia indicating where spotted wobbegongs live

EATS: Fishes and invertebrates on the ocean floor

THREATS: Not targeted by fishing, but may be threatened locally by habitat destruction in Papua New Guinea

ECO-FACT: Part of its range is protected by the Great Barrier Reef Marine Park

Whale shark

Whale shark

Whale shark
Rhincodon typus
Maximum Length: 65 feet (20 meters)

A whale shark swimming by

Largest fish in the world; can filter 162,000 gallons (736,000 liters) of water per hour. Whale sharks migrate thousands of miles between seasonal feeding sites.

WHERE: Tropical and temperate oceans worldwide, except the Mediterranean

map of world indicating where whale sharks live

EATS: Plankton, krill, fish eggs, fishes, squids, crustaceans

CONSERVATION STATUS: Endangered

THREATS: Frequently struck by ships when crossing shipping lanes; killed for their fins

ECO-FACT: Gives birth to live young; one female was found with 300 embryos inside

Nurse shark

Nurse shark

Nurse shark
Ginglymostoma cirratum
Maximum Length: 10.5 feet (3.2 meters)

two nurse sharks swimming

Whisker-like barbels on its snout help it find prey on the seabed at night, which it suctions up

WHERE: Tropical coral reefs, seagrass and mangroves in the Atlantic 

map of Atlantic ocean where nurse sharks live

EATS: Crustaceans and other invertebrates on the seafloor, bony fishes, rays

CONSERVATION STATUS: Vulnerable

THREATS: Targeted in some fisheries, and taken as bycatch

ECO-FACT: Has litters of 21-29 pups every two years with a six-month gestation period

Epaulette shark

Epaulette shark

Epaulette shark
Hemiscyllium ocellatum
Maximum Length: 3.5 feet (1.1 meters)

An epaulette shark "walking" by

Can survive out of water for an hour when stranded at low tide by slowing its heart rate; "walks" back to water on its fins

WHERE: Shallow tropical waters of Australia and New Guinea, commonly in reefs and tidal pools

map of Australia indicating where epaulette sharks live

EATS: Crustaceans, small fishes, worms

THREATS: The New Guinea population is threatened from overfishing and habitat destruction

ECO-FACT: Lays just two eggs at a time

 ANGEL SHARKS

Angel sharks have wide pectoral and pelvic fins that look like angel wings. The fins help them hide on the  seafloor, where they wait for prey.

Number of living species: more than 25

Pacific angel shark

Pacific angel shark

Pacific angel shark
Squatina californica
Maximum Length: 5 feet (152 meters)

Hiding angel shark swimming out of sand

Flat angel sharks with wide pectoral and pelvic fins like angels’ wings hide on the seafloor waiting for prey

WHERE: Eastern Pacific: Southeastern Alaska to the Gulf of California, and reported as far south as Costa Rica to Southern Chile, on the continental shelf 49-705 feet (15-215 meters) deep

EATS: Bottom-dwelling, reef, and midwater fishes; invertebrates; squid

CONSERVATION STATUS: Near Threatened

THREATS: Heavy localized fishing

ECO-FACT: Flat-bodied like rays, but are actually sharks

 

MACKEREL SHARKS

When most people think of a shark, it might be a mackerel shark. This group includes well-known giants like the great white shark and the basking shark, as well as the speedy mako and thresher sharks. 

Number of living species: more than 16

Great white shark

Great white shark

Great white shark
Carcharodon carcharias
Maximum Length: 21 feet (6.4 meters)

Great white shark swimming past camera

Bite can crush bones; ambushes from below; swims up to 35 mph (56 km/h) in short bursts and can breach water during an attack

WHERE: Entire ocean except polar waters

map of world indicating where great white sharks live

EATS: Marine mammals, fishes, sea turtles

CONSERATION STATUS: Vulnerable

THREATS: Overfishing, accidental capture and trophy hunting

ECO-FACT: May live 70 years; gather 1,000 miles from shore

Goblin shark

Goblin shark

Goblin shark
Mitsukurina owstoni
Estimated Maximum Length: 20 feet (6 meters)

gif of goblin shark biting an object

Slow-moving; can rapidly project its jaw out of its mouth to catch prey that would otherwise be too fast to capture

WHERE: Deep temperate and tropical Atlantic, Indo-Pacific and Western Pacific

map of world indicating where goblin sharks live

EATS: Fishes, squids, crustaceans

THREATS: Rarely caught as bycatch; habitat likely rarely overlaps with fisheries

ECO-FACT: Jaws are highly prized and are sold for up to $4,000 each; only surviving member of the 125-million-year old lineage Mitsukurinidae

Mako shark

Shortfin mako shark

Shortfin mako
Isurus oxyrinchus
Maximum Length: 14.5 feet (4.5 meters)

Mako shark swimming

The fastest shark in the world; can swim 31 mph (50 km/h), with bursts up to 46 mph (74 km/h); can leap 30 feet (9 m) out of water

WHERE: Temperate and tropical waters; migrates across oceans

map of world indicating where great mako sharks live

EATS: Mostly large fishes, squids, sharks, porpoises, sea turtles

CONSERVATION STATUS: Endangered

THREATS: Fished commercially for meat and fins; sport fishing

ECO-FACT: Matures slowly and reproduces once every three years, which makes it vulnerable to overfishing

BULLHEAD SHARKS

Bullhead sharks get their name from the ridge above their eyes. They live in rocky reefs in the Pacific and Indian Oceans.

Number of living species: at least 10

Port Jackson shark

Port Jackson shark

Port Jackson shark
Heterodontus portusjacksoni
Maximum Length: 5.4 feet (1.7 meters)

image of bullhead shark swimming in sandy waters

Small, sharp front teeth pierce shells of prey, and flat, back teeth grind them up; hides eggs in cracks for safety

WHERE: Seafloor along coast of southern Australia

map of Australia indicating where bullhead sharks live

EATS: Sea urchins, mollusks, crabs, shrimps, worms, small fishes 

THREATS: Frequent bycatch in commercial fisheries; often released alive

ECO-FACT: Flesh is poor quality, so it is not targeted by fisheries

SAWSHARKS

Sawsharks get their name from their long snouts, which have teeth sticking out at the sides. They use their snouts and teeth to slash prey. Don't confuse saw sharks with sawfish! Those are rays.

Number of living species: at least 10

Long blue-grey shark with saw-like nose

Shortnose sawshark

Shortnose sawshark
Pristiophorus nudipinnis
Maximum Length: 4 feet (1.2 meters)

image of short-nose sawshark swimming in deep waters

Uses the sensitive whisker-like barbels on its rostrum to find food

WHERE: Eastern Indian Ocean, Australia, Tasmania; on the continental shelf to 541 feet (165 meters) deep

EATS: Small fishes and invertebrates

CONSERVATION STATUS: Least Concern

THREATS: Caught as commercial bycatch

ECO-FACT: Whips its snout back and forth to stun small fishes and invertebrates before feeding on them

 

BRAMBLE SHARKS

Bramble sharks live near the bottom of the ocean. Scientists think they eat by suddenly expanding their mouths and throats. That lets them suck in fish like a vacuum cleaner.

Number of living species: at least three

Bramble sharks

Bramble shark

Bramble shark
Echinorhinus brucus
Maximum Length: 12.9 feet (3.9 meters)

model of bramble shark on top of a blurred background of the ocean

A stout deepwater dweller lacking the single big fin sticking up on its back that people picture when they think of sharks

EATS: Bony fishes, small sharks, and crabs

WHERE: Widespread, yet patchy, global distribution in the Mediterranean Sea, and Atlantic, Indian, and western Pacific Oceans; on or near the bottom, on continental shelves to 2953 feet (900 meters) deep

CONSERVATION STATUS: Endangered

THREATS: Liver oil considered very valuable by local communities; little species management across its range; also caught as bycatch

ECO-FACT: Large, thornlike denticles are scattered on its body and fins

COW AND FRILL SHARKS

Cow sharks and frill sharks have more gills than usual—six or seven pairs instead of five. Frill sharks have frilly skin around their gills.

Number of living species: five cow sharks and two frill sharks 

Sharpnose sevengill shark

Sharpnose sevengill shark

Sharpnose sevengill shark
Heptranchias perlo
Maximum Length:  4.6 feet (140 meters)

image of a sharpnose sevengill shark swimming

A small deepwater dweller with two more pairs of gills than most sharks

WHERE: Tropical and temperate coastal regions worldwide (except the northeast Pacific); on continental shelves to 3,280 feet (1000 meters) deep

EATS: Squid, cuttlefish, invertebrates; bony fishes; small sharks and rays 

CONSERVATION STATUS: Near Threatened

THREATS: Fewer landings suggest a population reduction of 20-29% over three generations

ECO-FACT: Its flesh is potentially poisonous

Frilled shark

Frilled shark

Frilled shark
Chlamydoselachus anguineus
Maximum Length: 6.5 feet (2 meters)

image of close up of mouth of frilled shark

May use its bright white, hooked teeth as lures to ambush prey; undulates like an eel and strikes like a snake; six pairs of frilled gills

WHERE: Deep coastal waters from 400–4,200 feet (120–1,280 meters) deep

frill-map

EATS: Squids, fishes, including other sharks 

THREATS: Low population, rarity, long gestation periods, deep-sea fishing

ECO-FACT: Because of its deep-sea habitat, little is known about this shark

Graphic that reads "Meet the skates and rays"

The flattened body shape of skates and rays makes them look like underwater kites. Their shape is well suited to living on the seafloor, although some rays live in the open ocean. Unlike sharks, skates and rays move by waving their pectoral fins.

SKATES

Skates have small, pointy teeth and short, stubby tails that are lined with thorny bumps. They reproduce by laying eggs in leathery cases.

Number of living species: more than 300

pacific white skate

Pacific white skate

Pacific white skate
Bathyraja spinosissima
Maximum Length: 6.5 feet (2 meters)

underside view of Pacific white skate

The second-deepest dwelling skate ever found

WHERE: Eastern Pacific from the Bering Sea south to the Galapagos Islands and Costa Rica; deep water rocky habitat to a depth of 9,639 feet (2938 meters) 

EATS: Deep-water bottom-dwelling fishes

CONSERVATION STATUS: Least Concern

THREATS: Potential expansion of deep-sea fisheries

ECO-FACT: Likes cold water; lays pairs of eggs in leathery cases with hornlike bits sticking out; embryos feed solely on yolk

STINGRAYS

Stingrays get their name from the venomous spines on their long, whiplike tails. They are not aggressive, but they may try to protect themselves if stepped on. Stingrays give birth to live young.

Number of living species: more than 245

southern stingray

Southern stingray

Southern stingray
Hypanus americanus
Maximum Disc Width: 5 feet (1.5 meters)

image of southern stingray swimming in sandy waters

Buries itself in sand to hide; breathes through openings on head called spiracles; tail has venomous spine

WHERE: Shallow waters on western Atlantic coast

ss-map

EATS: Crustaceans, fishes, mollusks, worms

CONSERVATION STATUS: Near Threatened

THREATS: Increased fishing pressure, particularly in Brazil 

ECO-FACT: Swimming with rays is a popular attraction for ecotourism

ELECTRIC RAYS

Electric rays have large organs on each side of their head that deliver electric shocks. They use them to hunt and to defend themselves.

Number of living species: more than 71

atlantic torpedo ray

Atlantic torpedo ray

Atlantic torpedo ray
Tetronarce nobiliana
Maximum Length: 6 feet (1.8 meters)

image of Atlantic torpedo ray hovering above sand

 Ambushes fish and stuns or kills them with an electric shock of 170 to 220 volts; adults are highly migratory

WHERE: Eastern and western Atlantic coasts

torpedo-map

EATS: Primarily fishes

THREATS: Occasionally caught as bycatch

ECO-FACT: Spawns in coral reefs, making it vulnerable to trawlers

GUITARFISHES AND SAWFISHES

Sawfishes look like a combination of a ray and a shark, whereas guitarfishes, with their flattened heads and expanded pectoral and pelvic fins, look like rays. Like sawsharks, sawfishes have long snouts with teeth sticking out at the sides. Guitarfishes have shovel-like snouts and are often called shovelnose rays. Because both groups are types of rays, their gills are on their underside. Nearly all species of both groups are critically endangered or endangered.

Number of living species: 5 sawfishes and more than 35 guitarfishes

bowmouth guitarfish

Bowmouth guitarfish

Bowmouth guitarfish
Rhina ancylostoma
Maximum Length: 10 feet (3 meters)

image of bowmouth guitarfish swimming

Heavily ridged tooth plates can crush shellfish; defends itself by butting predators with the lines of spikes above its eyes

WHERE: Tropical and temperate Indo-Pacific and West Pacific reefs and sandy bottoms

bowmouth-map

EATS: Mollusks, crustaceans

CONSERVATION STATUS: Critically Endangered

THREATS: Unregulated fishing for fins, habitat destruction, pollution

ECO-FACT: Population has fallen by at least 80%, but legal protections and safer nets have slowed the decline in Australia

graphic that reads "Meet the Chimaeras"

With huge heads and plate-shaped teeth for grinding food, chimaeras can be goofy looking. Their big eyes help them see in the ocean depths where they live.

Number of living species: more than 52

greyish-pink shark with long nose and protruding mouth

Pacific spookfish

Pacific spookfish
Rhinochimaera pacifica
Maximum Length: 5.4 feet (1.65 meters)

image of pacific spookfish swimming

This chimaera’s long snout has electroreceptors that help it find food in the dark ocean depths; unlike sharks, it swims by flapping its large front fins

WHERE: Coastal Pacific waters from 1,080–4,900 feet (330–1,490 meters) deep 

spook-map

EATS: Small fishes, crabs, mollusks, marine worms, sea urchins, octopuses

THREATS: Bycatch in deepwater trawls, but too deep for most fisheries

ECO-FACT: Thought to live 30 years

greyish-pink shark with brown stripes along it's back

Rabbitfish

Rabbitfish
Hydrolagus sp.
Maximum Length: 3.3 feet (1 meter)

Rabbitfish swimming in place

Swims by flapping its wing-like pectoral fins; can raise and lower a venomous spine attached to the dorsal fin on its back

WHERE: Deep ocean water, often below 2,625 feet (800 meters)

rabbit-map

EATS: Small fishes and invertebrates

THREATS: Retained as bycatch, but its range often does not overlap with fisheries 

ECO-FACT: Males have a barbed organ on their heads called a tenaculum that helps grasp females during mating 

Meet Extinct Sharks and Their Relatives

Scientists have identified thousands of species of extinct sharks. Earth’s extinction events wiped out many shark species. Diverse new ones evolved from the survivors. There’s a lot we don’t know about extinct sharks and their relatives. Because their skeletons were made of cartilage, not bone, they didn’t leave many body fossils behind. Most of what remains are teeth. Many, many teeth. Like the 7-inch (18 cm) teeth of megalodon. Here’s what we do know about a few gripping species.

imaeg of doliodus fossil in two slabs of stone

Doliodus

Doliodus
Doliodus latispinosus
Maximum Length: 40 inches (100 centimeters)

artist rendering of doliodus swimming

artist rendering

A key transitional fossil, its mixture of features from sharks and a group of early, extinct bony fishes shows that sharks descended from bony fishes, not the other way around

WHERE: May have lived in rivers, estuaries, or shallow coastal lagoons, as fossil teeth have been found near where ancient rivers entered the sea

ATE: Small fishes and invertebrates; grasping teeth were suited for snatching prey from behind

WHEN: Lived at least 409 million years ago

image of fossilized megalodon tooth

Megalodon

Megalodon
Otodus megalodon
Maximum Length: 50 feet (15 meters)

image of megalodon with mouth open showing teeth

artist rendering

The biggest predatory fish of all time, it's bite may have been stronger than T. rex's. It could open its jaws 11 feet (3.4 meters) wide.

WHERE: Warm coastal waters, sometimes open ocean

WHEN: Lived from around 23 million years ago to 3.6 million years ago

ATE: Whales, seals, sea cows, sea turtles, large fishes including sharks

ECO-FACT: Went extinct after the climate cooled and its smaller relative, the great white shark may have won the competition for prey

image of helicoprion jaw fossil

Helicoprion

Helicoprion
Helicoprion sp.
Maximum Length: 35 feet (10.7 meters)

artist rendering of helicoprion swimming

artist rendering

Known mostly from fossils of large, spiral tooth whorls that grew from the shark’s lower mandible. Older, smaller teeth slid forward as newer, bigger teeth grew behind them. Instead of falling out, the old teeth formed a spiral.

WHERE: Oceans worldwide

WHEN: Lived over 270 million years ago

ATE: Unknown, but it was the largest predator on Earth at its time

 

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Image Credits:

smooth hammerhead silhouette, The Natural History Museum, London/Science Source; smooth hammerhead, Shutterstock; bull shark silhouette, M. Shanley/© AMNH; bull shark swimming, Discovery Access; blue shark silhouette, M. Shanley/© AMNH; blue shark swimming, Klemens Gans/Bluewater Fascination; swell shark silhouette, Norbert Wu/Minden Pictures; swell shark underwater, Dave Lieberman/Diving Catalina; tiger shark silhouette, Fred Bavendam/Minden Pictures; tiger shark swimming, SCUBAZOO/NatureFootag; spiny dogfish silhouette, M. Shanley/© AMNH; spiny dogfish, Shutterstock; cookiecutter shark silhouette, M. Shanley/© AMNH; cookie cutter shark teeth, David Doubilet; American pocket shark silhouette, J. Wicker, NOAA/NMFS/SEFSC/Miami Laboratory; American pocket shark, Pally/Alamy; Greenland shark silhouette, Saul Gonor/NHPA/AGE Fotostock; Greenland shark swimming, NOAA; tasselled wobbegong silhouette, Manfred Bail/ImageBroker/AGE Fotostock; tasselled wobbegong, Elias Levy; whale shark silhouette, Zac Wolf; whale shark swimming, Discovery Access; nurse shark silhouette, M. Shanley/© AMNH; nurse shark swimming, Discovery Access; epaulette shark silhouette, Illustration by Zhao Chuang; Courtesy of PNSO PTE. LTD; epaulette shark walking, Plankton Productions Pty Ltd./NatureFootage; Pacific angel shark silhouette, BluePlanetArchive/Phillip Colla; Pacific angel shark swimming, Walter Marti/NatureFootage; great white shark silhouette, Nature Picture Library/Alamy; great white shark swimming, Common Flat Project LLC; goblin shark silhouette, M. Shanley/© AMNH; goblin shark biting, USFWS; shortfin mako shark silhouette, M. Shanley/© AMNH; shortfin makos shark swimming, Andy Brandy Casagrande IV/NatureFootage; Port Jackson shark silhouette, Blue Planet Archive/Nigel Marsh; Port Jackson shark, BluePlanetArchive/Andy Murch; shortnose sawshark, Andrew DeWater; bramble shark, Museums Victoria/CC BY-NC; sharpnose sevengill shark, Kelvin Aitken/VWPics/Alamy; frilled shark silhouette, M. Shanley/© AMNH; frilled shark close-up, © Citron/CC BY-SA 3.0; Pacific white skate silhouette, MBARI; Pacific white skate, Fisheries and Oceans Canada/CC BY-NC; southern stingray silhouette, M. Shanley/© AMNH; southern stingray, BluePlanetArchive/Phillip Colla; Atlantic torpedo ray, Fred Bavendam/Minden Pictures; bowmouth guitarfish, Blue Planet Archive/Alamy; Pacific spookfish silhouette, M. Shanley/© AMNH; Pacific spookfish, Kelvin Aitken/VWPics/Alamy; rabbitfish silhouette, M. Shanley/© AMNH; rabbitfish swimming, NOAA; Doliodus fossil, J. Maisey/© AMNH; Doliodus artist rendering, Illustration by Zhao Chuang; Courtesy of PNSO PTE. LTD; megalodon fossil, M. Shanley/© AMNH; megalodon model, M. Shanley/© AMNH; Helicoprion fossil, D. Finnin/© AMNH; helicoprion artist rendering, Illustration by Zhao Chuang; Courtesy of PNSO PTE. LTD.