If you have a cat, you are furmiliar with the habit your furiend has of wiggling their hind end right before cathletically pouncing, catching, and shredding whatever unfurtunate part of your body foolishly moved under the blankets. This leads to an idle curiosity - why do cats adjust their rear before pouncing?
John Hutchinson, a professor of evolutionary biomechanics at the Royal Veterinary College in London has several pawsible theories [livescience.com] that may tell the tail:
may help press the hindlimbs into the ground to give cats added friction (traction) for pushing them forward in the pounce
It may also have a sensory role to prepare the vision, proprioception [an awareness of one's position and movement] and muscle — and whole cat — for the rapid neural commands needed for the pounce
It probably does stretch the muscles a bit and that might help with pouncing
This isn't behavior unique to house-cats. Wild felines all the way up to lions and tigers litterally do this fur real in the wild.
On the subject of purforming a proper acatdemic study to determine an answer to this biting question, Hutchinson isn't kitten around
"it must be done, somehow. I shall marshal some scientists, and some friendly cats, in due course."
Stay tuned, if the study is done purfectly we may eventually be able to scratch off another timeless question. Which would be pawsome.