Are Sharks Fish?
- Thread starter Bengal Tiger
- Start date
I'm going to take you not clarifying your age as proof that you are actually not how old you claim to be...I suppose that is out of my control
No, you may want to read Tino's original post. She's confused why you think a bunch of strangers that you met online are better backup than all of this:
Yes, very many zoochatters are very knowledgable but there are all these other resources you could've used before creating a thread to ask an extremely obvious question
He was showing an example of something that resembles a fish and has gills but isn't a fish.
I supposed someone could argue that only Actinopterygii are true fishes.
That was a joke, Sirenia are the sea cows (manatees and Dewgongs).
The evolved version of SeelWhat's a Dewgong?
Autistics aren't always great at getting jokes
Thought they meant sirenidae. I don't get what manatees have to do with it.
@Bengal Tiger
This was less than a week ago... You really, really might want to make some serious effort into thinking about your posts and potential responses before you hit reply or create thread. You're literally on your last scrap of dignity on this site. It's getting very hard to respond to you in any sort of serious or non-condescending fashion.
This was less than a week ago... You really, really might want to make some serious effort into thinking about your posts and potential responses before you hit reply or create thread. You're literally on your last scrap of dignity on this site. It's getting very hard to respond to you in any sort of serious or non-condescending fashion.
I'd say not at all as whilst flightless birds aren't all closely related to each other, sharks are more closely related to other cartilaginous fish, than all tetrapods so I'd say no, unless you count chordates as fish (like how birds are reptiles), than sharks wouldn't be fish either. (Although you could argue fish is a simply a catch-all term, and if one was taxonomy speaking it'd be ray finned/ cartilaginous).Sort of true in a sense, but it's also like saying flightless birds aren't "true birds" because they can't fly.
Considering sharks fish is like considering birds reptiles. It is a valid taxonomic question. If we consider sharks fish why aren't all tetrapods fish?
The answer is of course that it would be silly to call all chordates fish and it is much more useful to have birds separate from reptiles, and tetrapod classes separate from fish classes. We should just be clear in recognizing that these are catchall terms and that 'fish' have a stunning diversity containing more classes than tetrapods. Regarding aquatic pre-tetrapod chordates as 'just fish' is like regarding non-vertebrate as just 'invertebrates'.
The answer is of course that it would be silly to call all chordates fish and it is much more useful to have birds separate from reptiles, and tetrapod classes separate from fish classes. We should just be clear in recognizing that these are catchall terms and that 'fish' have a stunning diversity containing more classes than tetrapods. Regarding aquatic pre-tetrapod chordates as 'just fish' is like regarding non-vertebrate as just 'invertebrates'.
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What?? I have never seen anyone try to say sharks aren't fish, unlike the bird/herp debate. Why would sharks being fish mean all tetrapods are fish? This makes no sense.
?? Why wouldn't it, unless you only group everything morphologically and have no care for taxonomy.
What is the logic for this?
Because sharks belong to a different class than bony fish. My point is not that sharks are not fish, just that there are many classes of fish and that we often forget that fact.
As a hypothetical I attempted to propose a line of reasoning as follows: If sharks, who have diverged from the main 'fish' class, bony fish, are fish, then why wouldn't tetrapods, which are descendants of lobe-finned fish, also be under fish, as they are all part of the same group descended from a common ancestor of sharks (cartilaginous fish), bony fish, and lobe-finned fish.
While I have not used that word on this site before, it indeed did not mean what I thought it meant.
I cannot comprehend how sharks being fish, which both live under water, have gills, can breathe through water, have fins, etc, also means that dogs and elephants and eagles are also fish.
Because from an evolutionary viewpoint what we call "fish" is not a monophyletic group. Some "fish" are evolutionary more closely related to elephants than to other "fish" , as they share a more recent common ancestor.
Source: Home
Because from an evolutionary viewpoint what we call "fish" is not a monophyletic group. Some "fish" are evolutionary more closely related to elephants than to other "fish" , as they share a more recent common ancestor.
Source: Home
That doesn't make mammals fish, though.
That depends on how you use the term fish. From an evolutionary standpoint it would have to be a monophyletic group, in which case mammals become highly modified fish. Which brings home the point that from a biological standpoint there is no such thing as fish (or every vertebrate is also a fish). If your definition everything with gills and no fingers/toes is a fish, that would pretty much cover what the general public sees as fish, but it would not be a evolutionary valid grouping.
This is a similar problem as to what is a reptile or not and comes from the fact that historical wisdom about what constitutes a monophyletic group has been overtaken by dna, which paints a more complicated picture...