[Inthacup]

Some of the results so far are laughable.

First, read what ClarkNasty wrote:

Animals somehow know they need to kill the other and fight to the death.

This is huge. It means that most of these animals are going to fight in such a way that we aren't used to seeing.

Exactly how do you people think the UFC Champ is going to kill the crocodile? punch him to death? use an armbar?

The fact is that a human with no weapons is a distant 8th. Most of these animals are too large and their skin is too thick. No unarmed human, not even The Ultimate Warrior, would stand a chance against any of these animals.

Tiver vs. Hippo is close for me, but that's because I don't know how a hippo will fare out of water.

Elephant vs. Grizzly: This seems pretty clear for the grizzly. We aren't talking about Smokey here. I think a full grown grizzly has the speed, agility and claws/teeth to inflict some serious damage on an elephant.