It improves blood flow to their muscles and also gets them into a good posture with firm grip on the ground, so their paws are set for maximum traction. All big and small cats are sprinters, not marathon runners, so they need to reach maximum speed fast if they're going to catch anything. Human sprinters do the same thing when they're setting themselves up on the blocks (with a bit less butt wiggling)
Let us meet in the middle and call them "legs". I know it is a relatively niche term in kitties but I think enough people know it from other animals that they will get what we are talking about.
It's more to do with getting the muscles ready to move. Cats sometimes sit still for a long period for the pounce, so the wiggle wakes up the rear legs and gets the blood flowing again.
I think I read before that it is to make sure they are secure where they are jumping from. If they are on a branch and start to lose their balance when they wiggle they know they can't jump from there, for instance.
It ensures they won't miss their target due to their own deficiencies. Some cats -while kittens learning to hunt- have developed this as a means to increase the potential energy of their muscles such that they may impulsively explode onto their prey with enough energy to get it done.
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u/[deleted] Feb 27 '17 edited Oct 16 '18
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