Telling the Difference b/t Undead and Human

[Groth]

I'm not sure if this goes in Survival and Defense or if there's a thread already, but I was thinkin last night, how can a zombie tell between a living human and an undead comrade. Is it smell? Pheromone? Or our body heat(i know they don't have heat vision)? 'Cause if it is smell, couldn't we just do something from House of the dead 2, or have dead animals and rotting things around, which brings the case, of bacteria and virus's. If it's body heat, you could pull somethin from Tremors 2, i think...and i have no clue what to do with the pheromone theory, but, shit, I'm just curious as to what you guys think. I know I'm probably way off.

Thanks,
Groth

[HOO-HAA]

Humans smell funny and kiss eachother and are stoopid. :puke:

[Zombie Survivor]

Well, the most conventional theory is that it has to do with scent. That they can smell us apart from the rest. Other sources say the movement en behavior e.g. Shaun of the Dead. There really isn't an definative answer.

[The Unknown]

How about the fact that Zombies look dead and are possibly missing a limb or a huge chunk of flesh and Humans arent.:?