natural structures

[mollykins]

I need to make two mind maps, natural and man made structures. I've got enough for man made structures but only have half a page for natural.

Can you please give me some ideas please. so far i have got (doing this from memory because my art book is to big to bike home with);

animals - skeletons, brain, genes, dna, foodchains

plants &formations - (structures of various parts of plants), family tree, great barrier reef, rock formations, weather (snowflake, tornados ect, ice crystals) gems stones.

[mrs_overall]

Stars,planets etc
Sand (deserts?) sand dunes, soil
Seas, rivers, lakes etc

[scotman]

certain types of animal shell
spider's web