Animal
People, Pets, and Wild
These pictures are all great. The ones you don't think are as great are still great, you just don't have the context for their greatness in your shared experience.
Vegetable
Flowers and Trees
I am an absolute sponge for shots of flowers and leaves when they have the right light and framing.
Mineral
Not Literally
I suppose 'inorganic' would be a more legitimate heading for this section, but it's just not as catchy. Nevertheless, you know what I'm about.