Answer By Rory Young
I am going to specifically answer this in terms of one male tiger going up against one male lion.
Although female lions hunt as prides, male lions spend most of their lives alone. They are forced out of the pride when they reach around two years.
If they manage to take over a pride of their own they will usually only manage to keep it for a couple of years. During the time they have a pride they will spend most of their time fighting off potential usurpers.
When they do not have a pride they frequently fight with other solitary males that they bump into and of course pride males in their attempts to take control of a pride.
So, a male lion spends his life fighting. In fact they spend so much time fighting and not eating properly and stressed out that they only live to about ten years old while females usually live to about fifteen.
The reason a male lion has a mane is for defense in fighting. They fight like wrestlers, facing off, gripping each other and trying to overpower each other. I have watched them fighting many times and have come across two dead males over the years. Both had been bitten through the spine. From what I have read, this is pretty much the norm.
So, the mane is a pretty effective defense in a cat-fight. To get round it requires some serious dominance in the fight as it means out wrestling the opponent to the point of being able to bite them through the spine. Tigers do not have this defense.
Tigers are solitary animals and although heavier than lions, they are shorter than lions at the shoulder. The weight difference is about 15% which is significant but not enough I believe to mean an overwhelming advantage for tiger, especially since they have a height disadvantage.
In terms of behaviour, male tigers usually solve their disputes via display and intimidation, preferring to avoid each other. Now in terms of fighting, this lack of experience when going up against a pro IS an overwhelming disadvantage.
This is like putting a heavy inexperienced amateur fighter in ring with a taller, leaner professional with a mean history of fights under his belt.
A no-brainer. The lion wins hands down. Size really isn’t everything..
EDIT: Yes, I agree a tiger in a zoo will kill a lion. The whole point I have been making here is that a male lion would probably win against a male tiger because a male lion has a lifetime experience of fighting other male lions. Male tigers do not usually fight except occasionally over a female in oestrus. A lion that had grown up in a zoo would obviously not have gained the experience!