is a shark a fish or a mammal?

Question

can someone help solve a debate, i think it's a fish as it has gills and all mammals breathe air however, i have been told its a mammal as it's offspring are born live thanx for any help

Answer 1

You are right, it is a FISH. A shark breathes through their gills like any other fish do. Shark is different from the Whale. Whales are large, magnificent, intelligent, aquatic mammals. They breathe air through blowhole(s) into lungs .

I suggest that the whale shark is the cause of confusion. Don't get confused with a whale shark to think shark as a mammal because of the "whale" in its name. Whale shark is just a kind of shark considered as the biggest shark and the biggest fish. It is NOT a whale.

You have to differentiate and specify 'Whale Shark' from a 'Whale'. Don't get confused if you see "Whale" before the 'Shark' ('Whale Shark').You see, you have to be careful when the name "whale is attached to the name." Just like the "Killer Whales" and "Pilot Whales", there is the name whale attached to their names yet they are not whales but dolphins but they are also mammals.

Anyway just bear in mind that 'Whale Shark' is a fish and all the rest of combined names bearing 'whale' are mammals- either a real whale or dolphins. (Examples: Blue Whale, Killer Whale, Pilot Whale, Humpback Whale, etc.)♥

Answer 2

Are Sharks Mammals

Answer 3

A fish. More specifically a cartilage fish. A mammal should have mammary glands, sharks don't.

I'm an advanced level biology student

Answer 4

A shark is a fish with a full cartilaginous skeleton,and like all other fish has a streamlined body.They respire or breath through 5 to 7 gills.Some species lay eggs and others are born alive.The young is called a pup.There are 3 ways in which pups are born:-
1)Oviparity-This is the process of laying eggs.Sharks which lay eggs include horn shark,catshark,Port Jackson shark and swell shark.Here in this process,the developing embryo is protected by an egg case.
2)Viviparity-Here there is a placental link between the mother and the developing baby like a mammal during the gestation period.The pups of these sharks(sharks with a viviparity system) are born alive and fully functional.Sharks which fall in this type of catagory are the hammerheads,the requiem sharks(such as bull and tiger sharks),the basking shark and the dogfish.
3)Ovoviviparity-Most sharks utilize this method.The young are nourished by the yolk of their egg and fluids from the oviduct wall.Like viviparity the young are born alive.Some species practice oophagy(like lamniforme sharks),that is,the first embryo to hatch eat the remaining eggs in the oviduct.The developing pups of the grey nurse shark take this stage further and consume other developing embryos.The survival strategy for the ovoviviparous is that the young are able to grow to a comparitively larger size before being born.Whale sharks are said to be in this group.

Answer 5

Fish. Whales are dolphins are mammals. However, a shark is most definitely in the fish category.

Answer 6

a shark is a fish a whale is a mammal and so is a dolphin

Answer 7

Shark, any of several fast-swimming, generally large fish known for their many sharp teeth, distinctive dorsal fin, and skill in locating underwater prey. Like other fishes, sharks are generally cold-blooded and breathe with gills. But unlike the more common bony fishes, which have skeletons made of rigid bone, sharks—and their relatives skates, rays, and chimaeras—have flexible internal skeletons made of cartilage.

Answer 8

Fish

Answer 9

Emucompboy is right.

The identification of natural groups of animals (called taxons or taxa) is based on unique characters or combinations of characters.

All mammals have:
- Hair (yes, even whales have remnants)
- Mammary glands
- A single bone forming their lower jaw
- 3 ossicles in their middle ear
...among other characteristics.

Not all mammals are viviparous (bear live offspring): the platypus and the echidnas lay eggs. Thus, this is not one of the unique mammalian characteristics.

"Fish" is not a natural group, but sharks are elasmobranch chondrichthyans (cartilaginous fishes).
As such, they have:
- Cartilaginous skeleton, frequently calcified but not ossified
- placoid scales
- copulatory claspers in males
- high urea concentration in the blood
...among other characteristics.

While a few sharks lay eggs, many are ovoviviparous or viviparous.
There are also many other animals that bear live young, including bony fishes (the livebearers, or killifishes), amphibians (some salamanders, caecilids and frogs), lizards, snakes, among vertebrates, as well as many invertebrates, such as echinoderms (sea cucumbers), insects, etc.

So you see, the reproductive mode has evolved so many times in quite different animals that it is not a good diagnostic character.

I hope this helps :-)

Answer 10

Some sharks come from eggs and some come living. but, as an add-on beta fish give birth to live young.
by the way, i'm 8