Not a silly questions , very interesting I think .
I've noticed 4 small teeth ( 2 top , 2 bottom ) in my Silver Dollars
They do? Wow, I learn something new every day. I had assumed they didn't since Mic bites me all the time and it never hurts.
Those species that feed on phytoplankton or zooplankton, along with those that have
tube-shaped mouths (the Syngnathidae), have no teeth. All other fish have teeth and
there is a wide variety of shapes, mainly in accordance with diet. These teeth can be
classified according to the bones on which they are situated: premaxillary and maxillary
on the upper jaw; mandibulars associated with the dental bone of the lower jaw; the
vomerine, palatine, ectopterygoid and parasphenoidal teeth in the palate; and in some
species (salmonids, osteoglossidae – Bony tongues ), there are dental plates associated
with the tongue equipped with prominent, sharp teeth; there are also pharyngeal teeth in
many of the branchial bones (see the diagram to the right).
Predatory fish, feeding on nekton and macrobenthos, have mandibular dentition made
up of numerous small but sharp teeth, canine in shape, which form an insuperable
barrier for small prey. The more active predators have strong jaws and sharp teeth. The
teeth on the edges of the jaws are for catching and chewing the prey, while the
pharyngeal teeth stop the prey from escaping. Corallivorous fish have grinding teeth,
similar to those of mussel-eating fish. Scaridae (parrot fish) have a beak-like mouth
with flat grinding plates of fused teeth for breaking up coral. The Cyprinidae (e.g., the
carp) do not have teeth at the edge of the jaw, although there are teeth at base of the
pharynx. Generally, these fish are vegetarian, but they do take in large mouthfuls of
mud and take nourishment from the small invertebrates the mud contains.