The ancestors of snow leopards took advantage of what is called an "open niche". The mountainous regions of central Asia 1,200 - 6000 meters (3,900 to 20,000 feet) above sea level were not inhabited...
Yes. It can. The snow leopard just lives in snow for six months of the year!
Snow Leopards can live without snow but they are more specialised to hunting in snow so it would make a difference.
By climbing up the tree and sleeping there
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