sitting down/moving away= respect
just standing around= just wants to be left alone
jumping forward suddenly= aggressive/scared
standing up: curious
flat ears: AAAAAAA
up ears: listening
do more bluffing than fighting
greetings: rubbing against other bear and sniffing
talking words: blowing, teeth clacking, grunting, huffing, clicking, growling, andotherstuffprobably

There can be and probably are a bunch of hybrids
black bears are s m o l brown bears are medium polar bears are b i g
they eattttttt literally everything
their dens are anything that can fit a bear
they have their own little spots in the territory that are theirs but they have bear friends and there are sometimes little gangs of young bears hanging around together and sometimes they randomly teach younger bears stuff
bear agesssss—
mating bears don't stay together buttttt you can just like assume a loophole where they have a cub and then their best friend who they love very much helps them raise it
0-1 years: baby
1-2 years: smol
3 years: teenager
4-7 years: young adult
8-15 years: adult
16+: old
and yeah!