i would not want to fight an animal in their own environment.
so i would absolutely not fight a shark. why? because it cant come on land, so it'd have to be in the water. and you are fucked in the water. it can drag you under, people are not mobile in the water, have limited visibility. you would absolutely lose to a shark if it really wanted to kill you.
a tiger in the jungle? terrible. you'd just be stalked and ass raped. those claws would murder you. there'd be nowhere you could go. you cant outrun a tiger, you can't outpower a tiger, and it would move like the wind with those kitty reflexes. i feel like i wouldnt even be able to touch it without being mangled or dismembered by those fangs.
a bear? hmmm. more powerful than a tiger, yes. but they're probably not quite as quick. i feel like if i needed to i could gouge a bears eyes out and stand a fighting chance. a tiger? i think making any move for its face would result in it biting my hand off. plus i cant see an environment playing much of an advantage to a bear.
so that said, i'd fight the bear.
yeah but how fast can a tiger run, and jump, and climb.
im just saying the environment doesnt help the bear. not like the jungle helps a tiger in terms of stealth or the water helps a shark by limiting human mobility and strength.
bears will definitely fuck you up, but i dont think it would be as lopsided a fight as with the others. plus, with a weapon, i think i could spear a bear in the heart. a tiger? shit those things are lightning fast. so are sharks in the water.
i just think of it in terms of living and dying. and to beat something that outpowers you like they all do, you have to gouge its eyes out. you cant just kill it outright with your bare hands. honestly, what are you going to do, kick it to death? no. shark is out of the question. you lose. tiger i dont honestly think i could get to its eyes. a bear? maybe. just maybe.