[Genesis (OP)]

We are all aware of the strength of our cold blooded cousins and the speed that some of them can attain but mammals have the advantage of stamina as a result of a higher metabolism.  On a one-to-one battle of equal size, for instance a large lizard v bear, what would come out on top?

Are reptiles stronger than mammals kg per kg?

[RD]

Jaguars 1 Crocodiles 0 ...

[CliffordK]

Interesting.
It may depend on who gets the first bite, and whether the battle occurs on land vs water. 

An interesting standoff between lions trying to steal a hippo  from crocs.  The lions got quite a bit of meat of of the hippo (I think), but the crocs didn't venture too far onto land, and the lions didn't venture too far into the water.

With snakes, apparently sometimes the snake wins, and [url=https://www.youtube.com/watch?v=GXy8uIXroPE]sometimes the croc wins.

[Kryptid]

That's going to depend on which particular species you are talking about.

[Nizzle]

In the arctic regions, you can bet your money on the mammal

[Monox D. I-Fly]

In the arctic regions, you can bet your money on the mammal

Are there even any reptiles in the arctic regions?