"Animal, Vegetable, Mineral" is a popular guessing game for normal things we may encounter. From these three categories, which category is this "thing" we are considering? It's a pastime. It is based on Science, but it is not science.

Within Science, we have the category of "lifeforms.""Lifeforms" are classified as that, when they demonstrate certain abilities. One is to be moveable in a self-operating moveability. (They move or move around at will.) Another is that they are regenerative. Through some process they replicate themselves. (That is a most-important quality.)

There are various strategies for reproduction. A primary one is mitosis (single cell division to become multiple cells). This happens with primitive simple lifeforms; but within complex lifeforms cellular division is also very active. Reproduction can also be asexual and/or sexual.

Lifeforms includes plant and animals, as we know from our daily lives. But it also includes many microscopic entities, such as bacteria, paramecium, and possibly even viruses. In recent years Fungi (that were formally considered to be "plants") are now considered to be in their own separate category.

So, the fallout from all this is that the popular "animal, vegetable, mineral" game would exclude fungi--since they are none-of-the-above.

But Fungi are clearly lifeforms (!). They reproduce by means of spores. (Not seeds, eggs, or live births, for instance.) Fungi includes molds, yeast, mushrooms, and toadstools. A mushroom or toadstool are comparable (in most respects) to a flower in a plant--being their method of reproduction.

It just so-happens, as with certain plants, there are fungi that animals can safely consume (eat for nourishment), and many that they cannot (because they are poisonous).

Knowing all this, it is easy to understand why fungi were formerly considered to be "part of plants." But the fact that they exploit spore-reproduction is a basic reason for making them separate from animals and plants.

All lifeforms (apparently) have the ability to evolve (if we accept the precepts of evolution).