Little Ray Stingray and Shark Book
July 2018 by V. R. Duin

FISHY FISH:
CARTILAGINOUS FISH
WITHOUT BONES OR SCALES

Sometimes when we trip or fumble,
Teamwork may just stop our stumble.
That's why we must always show respect
To help that comes as we least expect.
(“Little Ray & Shark Patch Things Up”)

“Fishy Fish” uses information from “Little Ray & Shark Patch Things Up” to show differences between stingrays and manta rays and sharks. These cartilaginous fish without bones or scales, may have teeth and have tongues, but they have no bones and they have no scales.

Are stingrays part of the shark family? Yes. This article adds to the information in “Little Ray & Shark Patch Things Up” about fish in the shark family. Rays, including the giant manta, are part of this family. The book and this website are about these fishy fish. Children enjoy comparing stingrays, rays and sharks. Although there are differences, rays are in the shark family. They have a lot of things in common. They are cartilaginous fish without bones or scales. Rays and sharks have no bones and they have no scales. Stingrays, rays and sharks may not look alike. They may not act alike. Many of them live and hunt alone. However, all fish need other fish to survive and to have babies. Rays and sharks may join fish of their kind for group travels, hunts and to find a mate.


Notice the body shapes. It is from differences that children may learn the most. Comparing these shapes to people is very hard. It can be hard to find the body parts. Differences make it hard for stingrays, rays and sharks to get along. People look more like each other than these fish do. Little Ray and the shark in his story work hard to become a team. Children also can learn to get along together. The fun facts in Little Ray's stingray and shark book for children make a lot of things clear about body shapes. They show how these fishy fish are different, and how they are alike. Children should explore the body shapes of all fish in the shark family. They might be surprised by the huge size of giant mantas and of whale sharks. It might come as a big surprise that sharks can be tiny. Children will discover there is a shark that looks like a stingray. There are many surprises in the shark family.


What makes a fish cartilaginous? Cartilaginous fish are made of cartilage. Cartilage is a white material. In humans, cartilage is outside the ear. Cartilage also is in joints and other body parts inside the body. Human babies have more cartilage than adults. This cartilage is slowly replaced by bone. Sharks are an ancient fish. They did not lose their cartilage over the centuries they have been on earth. Many fish have bones. Stingrays, rays and sharks have no bones. Like bones, cartilage can break and wear out. As children study the differences between stingrays and manta rays and sharks, they learn sharks have no scales. The skins of rays, stingrays and sharks do not feel like the cartilage of people. Sawfish, guitarfish and skates also are in the shark family. All of these fish have cartilage instead of bones. Studying fishy fish gets children thinking. They learn how different shapes, forms and styles may help, change or stop these fish from doing some things.


Do Stingrays and sharks have to keep swimming? Most fish have swim bladders to help them float in water. Fish in the shark family have no swim bladders. Swim bladders help fish move up and down in the water. This keeps them from sinking too low or floating too high. Swim bladders also may help fish stay alive in dirty water. Some fishy fish have to keep swimming. If they stop, they will sink. Manta rays have to keep swimming. Hammerhead sharks have to keep swimming. Stingrays and electric rays spend a lot of time sitting still on the ocean floor. As children study stingrays, rays and sharks, they learn how some sharks gulp air to push water over their gills. This lets them breathe without swimming. It takes a lot of energy, so they cannot keep this up for long. Some sharks store fats and oils in their livers to make up for their missing swim bladders. Stingrays have special breathing holes to help them breathe without swimming.


Do stingrays and sharks have gills? All fish have gills for breathing. Lungfish have gills and lungs. Lungs are inside the body. Gills are outside the body. Gills are on each side of the head of most sharks. Children can look for these gills behind sharks' eyes. The gills of stingrays, mantas, other rays and of some sharks are under their heads. Most stingrays and sharks have five pairs of gill slits. Each of these slits open into one gill. The large number of slit openings into the gills of fish in the shark family is unique. Bony fish have just one opening to the many gills in each side of their heads. Sadly, manta rays are killed for their gills. Some people think manta gills make good medicine. When children compare stingrays, rays and sharks, they get a better understanding about different ways to breathe. They also learn to value these fish, so they can remain free in nature.


How do gills work? Gills are used to breathe. Before they are born, people have body parts that work like gills. Bony fish pump water from their mouths to their gills. Some sharks also pump water to help them breathe. Stingrays do not pump water. To help them breathe, stingrays and some sharks have breathing holes. These are in addition to gills. Spiders and insects also have breathing holes. These holes are on their bodies, not on their heads. These holes are called blow holes in whales and dolphins. Blow holes help these mammals with lungs breathe. These holes are on the heads of water animals that have them. These holes make it possible for fish to stay still in the water. The breathing holes are called “spiracles”. Spiracles also may help fish find food. Great White, Hammerhead, Mako and Whale sharks have no spiracles. These fishy fish have to move to breathe. Manta rays also have to keep swimming. Their spiracles are small and don't work. The shark family can teach children a lot about people and other animals.


Do rays and sharks have fins? To learn about stingrays, rays and sharks, children must stop and think. Slow study makes it possible to discover new things. Fish, including cartilaginous fish, have pairs of pectoral fins on the side of their bodies. These fins are mostly used to move through the water. Baby frogs also have these fins. As frogs grow, these fins turn into legs with feet. As children study rays and sharks, they learn stingrays do not swim like sharks or most other fish. Stingrays swim with their large, wing-like pectoral fins. Sharks and many other fish use their pectoral fins to steer. Some stingrays use a wavy motion to move through the water. Manta rays and some other rays flap their pectoral fins like bird wings. Manta rays are beautiful movers. The triangle-shaped dorsal fin of a shark appears when the fish is near the surface. The dorsal fins in stingrays, manta rays and other rays are very small, or missing.


Sharks are the only fish that cannot swim backwards. When pulled backward by their tails, the gills of sharks fill with water. This kills them. Sharks move their bodies and push with their tail fins to swim. Sharks often cruise at a fairly slow speed. However, among the fastest and best swimmers in the ocean are Lamnid Sharks in GURPS. Since sharks do not do well in tanks, their speeds are hard to measure. In aquariums, stingrays and sharks have no need for speed. Hammerhead sharks swim on their sides. Flounders are flat fish. Their eyes are on one side of their bodies, so they also swim on their sides. As children compare rays and sharks, they discover electric rays also are cartilaginous fish without bones or scales. Because electric rays move with their tail fins, they tend to be slow and lazy swimmers.


Fish have a head, with a mouth and eyes. However, these body parts do not look or work alike in different fish. A stingray's mouth is under its body. According to the Sphyrnid Sharks in GURPS, or hammerheads, have eyes mounted on each end of their hammer-shaped head. Sharks' eyes are on the sides of their heads. The eyes of a stingray are on the top of their heads. The eyes of a manta ray are on the side. Mantas cannot see food in front of them. Sharks use their eyes to find food. A shark's mouth is in the front of its head. Manta rays also have mouths facing toward the front. A shark's mouth is much larger and more dangerous than the mouth of a stingray. The danger comes with the teeth, not the size. A giant manta has a very big mouth, but it cannot bite people. Electric currents can be detected by electric rays, stingrays and sharks. Children can compare fish heads, mouths and eyes to those of people and other animals.


Do fish have a good sense of smell? When children compare fish, they think about details. A stingray's nose is under its body, as are its nose holes. Remember, the nose holes are used for smelling. The breathing holes are used for breathing. The noses of all cartilaginous fish are on the underside. The nose holes of a fish are called nares. The nostrils of flat-faced dogs may be called nares. The nostrils of these dogs are narrow. This makes it harder for them to breathe. However, this name also makes things confusing. Nares are not like nostrils. The nares of a fish are not connected to the mouth or throat, like nostrils of people or dogs. Nares are not used for breathing. Nares give fish a good sense of smell. Sharks have a very good sense of smell. It is their best tool for hunting. They can smell out food, mates, predators and relatives.


Can fish hear? Some fish have a good sense of hearing. Hearing helps fish get around in muddy or dark water. It also helps them hear nearby food, enemies or friends. Fish do not have ear openings outside their head. The hearing parts are inside their bodies. Sounds are made by vibrations. Some fish hear sounds with ear parts. Some fish use lateral lines to feel these sound vibrations in the water. Some fish hear better than people. The sense of hearing is linked to the brain. Animals hear different sound frequencies. Some fish hear sounds at frequencies that people cannot hear. They also may hear sounds from a greater distance than people. Learn more from DOSIT at What sounds can animals hear?.


Do fish have good eyesight? Children learn a lot by seeing. Not all fish can “see the light”. A good sense of sight depends upon light. Some fish are blind. Stingrays have weak eyesight. However, the eyes are located well. Rays can keep watch from their hiding places in the ocean floor. This is where stingrays spend most of their time. Sharks and manta rays spend most of their time on the move, hunting for food. Manta rays and whale sharks do not need to see their food. They swim through food-rich areas, sucking in food as they move. Most sharks have good eyesight. Few fish can see in the dark. In dark and muddy water, most fish find their way thanks to sounds and a good sense of smell. The fish that light up, or glow in the dark, are not trying to see. They may be trying to attract a mate or send a warning. Some fish need periods of light and dark. Some fish live in total darkness. Many animals find their way around without good eyesight.


Do sharks have tongues? Do sharks have taste buds? Most fish have tongues or something like a tongue. Fish with tongues may not use them for tasting. The taste buds of sharks are in their mouths and throats. A shark's tongue is on the floor of the mouth. The tongues and the taste buds of a shark are small and made of cartilage. Bony fish have bony tongues. The tongues of these fish are called “basihyals”. All fish have taste buds or a sense of taste. Taste can be on the body surface of some fish. Catfish and saw sharks have whiskers, called “barbels”. They use these for tasting. Taste buds help stingrays and sharks decide what to eat. When children compare rays and sharks' body parts and habits, they practice higher-thinking skills. These skills help them do well at school and at work.


Do stingrays have tongues? Do stingrays have taste buds? Stingrays have tongues like sharks. Stingrays also have taste buds all over their mouths and throats. Stingrays and sharks are food tasting and processing machines. These fishy fish also can vomit to rid themselves of food they cannot digest. It also makes room for the next meal. As children explore the differences between stingrays and manta rays and sharks' body parts. They also learn how these cartilaginous fish without bones or scales compare to and differ from other fish and people. Some bony fish have teeth on their tongues. These strange teeth are used to hold food or to suck blood from it. Unlike most fish, the lamprey can stick out its tongue.


Can rays and sharks live in fresh water? When children compare rays and sharks, they learn about fish habitats, they also learn important facts of science. Humans and most other land animals cannot drink saltwater. The salt makes them thirstier. Too much salt can kill people and animals. Bull Sharks, River Sharks and some kinds of stingrays can live in fresh water. The website for freshwaterstingrays.co.uk provides interesting facts about the rays and sharks that are able to live in freshwater. Most saltwater fish, including stingrays, rays and sharks would die in freshwater.


Do rays and sharks drink water? Unlike their bony fish cousins, cartilaginous fish do not drink water. Life in saltwater is complicated. Members of the cartilaginous fish family have developed different means of pumping or sending salt back into the water. Stingrays and sharks get water from their food. Water also enters their bodies through their gills. These fishy fish do not drink water. They also do not leak water like other fish. To lower salt concentrations, sharks make urea. The urea is sent into the water by a gland near the anus. As children compare stingrays, rays and sharks, they learn the digestive systems of these fish are very much alike. Fish have no saliva to begin digestion.


Are all rays and sharks deadly? Stingrays and sharks may be deadly. Learning about the eating habits of these fish, helps children keep an open mind. Sharks can hunt and make catches in the water and in the air. Not all rays are stingrays and not all sharks are deadly. Some of these fish have teeth. Some of these teeth are sharp. Some of these teeth are flat and dull. Different teeth are used for different food. Stingrays and some sharks have stinging spine barbs with venom. The most feared of sharks can be playful and curious. In shallow and deep waters, sharks eat many types of food. They do not eat a lot of people. They eat bony fish, other fishy fish, squid, sea turtles, sea stars and mammals. They eat food that is living, dying or dead. Sharks can take large bites. Bull sharks eat almost anything in the water. Hammerhead sharks feast on stingrays. Giant mantas and whale sharks eat tiny food. They are not dangerous to people.


Sharks often work as scavengers. As scavengers, these cartilaginous fish without bones or scales have an odd competitor. The hagfish is among the strangest of scavengers. It has teeth, but it does not need them to eat. The hagfish takes in food through its skin. Stingrays, rays and sharks swallow their food. Like sharks, some stingrays hunt for food in the water. However, most stingrays are bottom feeders. They poke around in the sand with their snouts and wings, looking for food. Sometimes, they wait for food to come their way. Stingrays are good at ambush. Stingrays can dig trenches with their fins. This helps them find prey buried in the ocean floor. As children compare stingrays and manta rays and sharks' teeth, tongues and hunting habits, they discover a lot of differences among these interesting fish.


Do rays live with sharks? Stingrays, manta rays, other rays and sharks live under different conditions. Unlike sharks and deep ocean manta rays, stingrays tend to stay in shallow, warm waters. Fortunately, plenty of stingray food lives in their hunting ground of little depth. Stingrays dine on fish, snails, shrimps, crabs, worms, clams and other creatures. They stir their food up from the ocean floor. The freshwater rays add insects, including mosquitoes and their larvae, to their diet. Stingrays have hard plates to crush food. Manta rays filter tiny foods into their mouths. When adults help children compare, contrast and analyze these cartilaginous fish without bones or scales, they encourage a curiosity for learning. Children also start to organize their world.


Stingrays are not scavengers. Sharks will eat dead food and gobble up non-food objects. Stingrays prefer small, fresh, live catches. In aquariums, stingrays will eat processed foods. As children analyze the differences among cartilaginous fish, they learn about fish habits and behaviors. Stingrays, electric rays and sharks have electro-receptors for hunting. They are able to detect the electrical charges given off by their prey. This helps them find hidden food. Rays use their teeth to chew food. They may do test bites. They do not bite in self-defense. Sharks may swallow food whole. As children compare stingrays, rays and sharks' teeth, they learn rays and sharks are always ready to eat. Whether swimming or resting in the sand, they stay alert for food. Manta rays swim in areas that are filled with food. They do not have or need real teeth or electro-receptors.


Is a stingray bite dangerous to a person? When children study the differences between stingrays and manta rays and sharks' teeth, they learn about survival. The bites of a stingray are fairly mild and may not leave any marks. Sharks dine on flying, swimming, floating and resting animals, as well as those felled by death. The bites of a shark may not leave anything behind. The bite of a shark can be very dangerous to humans. The mouths of these cartilaginous fish without bones or scales are designed for their different hunting and dining styles. Manta rays do not bite at all. Asking and answering questions about fish and their teeth, tongues and other body parts starts a lifetime of learning.


Are there teeth in the mouths of fish? As children compare stingrays, rays and sharks, they learn that not all fish have teeth in their mouths. Manta rays and whale sharks have teeth in their throats. These are used to filter plankton. Manta rays do not grind food. Their teeth are not like those of other fish with teeth. Sharks are in serious need of a tooth fairy. They shed tens of thousands of teeth during their lifetimes. Lost shark teeth are replaced. Divers and beachcombers commonly find shark teeth. Stingray teeth findings are rare. A stingray might shed an occasional tooth, while crunching food with hard shells. That tooth will be replaced. Stingray and shark teeth, denticles and taste buds may have developed from the same cell.


How long do rays and sharks live? Rays and sharks may teach children about time management. The lifetimes of these cartilaginous fish without bones or scales differ greatly. As children compare these fish, they learn the lifetime of stingrays is shorter than that of their shark relatives. Stingrays usually live for about twenty years. Manta rays also can live for about that long. The lifetimes of sharks can last for centuries. Greenland sharks break age records for animals with their long lives. Some turtles, tortoises and whales also live for a long time. There are trees on earth that outlive all animals. The lifespans of Greenland sharks may reach 400 years. Humans don't live long enough to accurately count the number of years passed or the number of shark teeth shed.


What are shark teeth made of? Sharks' teeth are longer versions of the tooth-like projections covering their bodies. These unique cartilaginous fish family cells regrow. Shark teeth are arranged in rows that slowly move forward from the back of the jaw to the front. As the front teeth wear out or fall out, new rows move from behind to replace them. These shark teeth replacements happen about every two weeks. Tooth damage and replacement can be accelerated by snacking on cans, tires and other garbage that humans toss into sharks' habitat. As children compare rays and sharks' teeth, they learn sharks have huge appetites to go with their huge life spans.


Do stingrays have teeth? When children compare rays and sharks' teeth, they are learning about tools of survival. Fishy fish have different shaped teeth depending on what food they eat. Stingray teeth are small and flat. Their teeth also are replaced much like sharks' teeth. Sharks that eat shellfish and crabs have flat crushing teeth. Sharks that eat fish have pointed teeth, while those that eat seals and sea lions have razor sharp teeth. The teeth of some cartilaginous fish family members are non-functional. This lack of chewing and biting ability is a huge difference between a manta ray and its shark and stingray cousins.


Do all rays have teeth? Manta rays and whale sharks use sucking mouth parts instead of their useless teeth. There is a strong association between chewing and tasting for hunger satisfaction. Despite the presence of teeth, sharks and rays may swallow their food whole. Many people also take this fishy fish short cut for immediate satisfaction. Ancient members of these cartilaginous fish species may have had jaws that evolved into the formation of teeth. As children compare rays and sharks, they learn electric rays have rows of small teeth that are sharper than those of most stingrays.


Do stingrays and sharks have scales? When children discover the differences between stingrays and manta rays and sharks, they learn about protective materials. Most fish have scales for protection. Unlike most other fish, sharks and stingrays are cartilaginous fish without bones or scales. Stingrays, manta rays and sharks have no scales. Instead, in those species that have them, they have skin projections that are made of the same structure as their teeth and stinging spines. The location of the tooth-like stinging structures in sharks is different from that of stingrays. Contact with shark skin can cause injuries.


Is shark skin useful to people? The skin of a shark feels like sandpaper to human touch. Primitive people used shark skin as sandpaper. The projections on the skin of these fishy fish are called dermal “denticles”. The denticles are arranged in a regular pattern in sharks and in an irregular pattern in stingrays. Because the bumps in sharkskin tend to repel germs, a company named Sharklet Technologies, Inc. is creating plastic wraps designed with bumpy sharkskin-like scales to fend off sources of infection in medical settings. According an article published by the Center for Disease Control and Prevention, Healthy Pets, Healthy People, pet fish can transmit germs to people. Fish can contaminate the water in which they live.


Can rays and sharks grow new skin? When children explore the differences between stingrays and manta rays and sharks, they learn safe practices. Fish protection developed from the same genes as hair and teeth in humans and other mammals. Unlike other types of fish scales, the dermal denticles of these fishy fish do not get larger as the fish grows. Instead, these cartilaginous fish without bones or scales grow more dermal denticles to fill in the larger space. Stingray skin has a bead-like appearance that feels slimy to the touch. Shark skin is armor-like in nature. Stingrays and manta rays have rough skin.


Can shark skin hurt a person? Shark skin can be hazardous to produce, so it is no longer commonly used for sandpaper. If the dermal denticles are removed, shark skin may be used to make leather products. Unsurprisingly, the dermal denticles of a shark can injure prey. As children compare rays and sharks, they learn the skin of electric rays is soft and flabby without denticles or horns. The skin of electric rays is smooth and untextured. Cartilaginous fish without bones or scales are suited to their environment and hunting styles. Other fish without scales include clingfish, eels and anglerfish. Some fish are coated with a slimy mucous that reduces friction for swimming.


Can fish live out of water? Life in the water is a characteristic of most fish. When children explore the differences between stingrays and manta rays and sharks, they learn about adaptation and creative thinking. A few fish can live out of water for brief periods, such as eels, snakefish, climbing perch, mudskippers or walking catfish. Lungfish can survive for long periods out of the water, which is particularly helpful when their habitat goes dry. Few fish can survive when their gills remain out of water. The time that it takes to photograph a trophy fish before release often results in immediate or painfully slow death.


Do stingrays and sharks travel long distances? Stingrays prefer shallow waters that are near shore. They move to warm parts of the world. Sharks may move to warmer temperatures. Some sharks cruise along the water surface. Sharks can live in deep, dark, cold depths. Like stingrays, sharks may come close to shore. Electric rays are can live in shallow water along shorelines or in deep water. Like stingrays, electric rays mostly are bottom-feeders. Children might want to further study electric rays. The shocking ability of electric rays may blow their minds. There are electric fields on land and in water. Some fish make electricity. Others just feel it. These fish use their electric sense for hunting. As children compare rays and sharks, they will learn little is known about these fishy fish.


Are rays cold-blooded? When children compare the differences between stingrays and manta rays and sharks they learn about inventiveness. Since most fish are cold-blooded, they take on the temperature of their environment. This is why stingrays stay in warm, shallow waters. They cannot raise their body temperature for deep, cold water hunts. As any swimmer or scuba diver knows, water drains body heat faster than air does. Wet suits and heated pools are used for human protection. Some bony fish and cartilaginous fish without bones or scales have heat-producing abilities.


Are sharks cold-blooded? Some sharks, like the Mako and Great White Shark, can raise the temperature of some body parts. This provides some protection and improves performance in cold waters. According to Pizard's GURPS Miscellanea, Alopiid Sharks are warm-blooded. Like rays, these sharks use their long whip-like tails for defense. Alopiid sharks also use whip-like tail lashes to catch food. They stun it or swat it into tight groups for eating. As children compare rays and sharks, they learn a lot about ocean life. They also bust myths about sharks and rays. The fishy fish family is big and interesting. Stingrays, manta rays, other rays and sharks are sure to keep children exploring and learning.


Differences between stingrays and manta rays and sharks:

  • cartilaginous fish family Little Ray says:

    Some cartilaginous fish can be purchased from tropical fish stores, but stingrays and manta rays and sharks don't belong in the same aquarium.

  • compare stingrays and sharks Little Ray says:

    In Little Ray's books, cartilaginous fish travel together, so children can compare them and learn critical thinking skills.

    • fishy fishLittle Ray says:

      Encounters with stingrays and sharks may require protective equipment to keep people safe, but manta rays won't stir up trouble.