[addicted2sp33d]

Strictly speaking from scientific taxonomy, sharks are not fish, but only because there really isn't a single scientific group called "fish"... sharks are in their own class because they are not bony fish, like WSB or YT.

However, commonly accepted definitions of the word "fish" includes anything that has gills, swims in water, and is generally cold blooded, which does include sharks... and incidentally includes some other "oddities" like some gilled salamanders.

In school, I was always taught that sharks ARE fish... whales/dolphins are not (because they breath air and are warm blooded)... but there are certain species of sharks and tunas that are able to maintain a core temperature that is higher than the surrounding water (e.g. they're warm blooded).

The Phylum Chordata includes all animals with backbones (aka vertebrates), but that's where the classification between "shark" and "bony fish" diverge... so that's a pretty fundamental difference.

Here's our friend the Tax Man:

Kingdom: Animalia
Phylum: Chordata
Class: Chondrichthyes (aka Cartilagenous fish... e.g. sharks, skates, rays, etc)
Subclass: Elasmobranchii
Order: Lamniformes
Family: Lamnidae
Genus: Carcharodon
Species: C. carcharias

Here's our friend the WSB:

Kingdom: Animalia
Phylum: Chordata
Class: Osteichthyes (aka bony fish... e.g. tuna, rockfish, bass, etc)
Subclass: Actinopterygii
Order: Perciformes
Family: Sciaenidae
Genus: Atractoscion
Species: A. nobilis

Clear as mud right? In the end, who really cares what it is? That lady was clearly off her rocker, and you can't reason with people in that state.

You can't out-crazy a real crazy-person.