Things that make kitties jump

Oh the things that make them jump and startle! I have a confession to make:
Today, I made both the kitties practically jump right out of their skins!

I call Dot my "tummy cat", because she loves having her ample tummy rubbed
and kissed. I noticed that Dot was lounging on her cat seat after getting
some kitty treats, so I reached around to scritch her wonderfully squishy
tummy flap.

It was then that she abruptly turned from a picturesque curl of sleeping
cat into something resembling a violent chemical reaction of exploding
black foam boiling above and over the side of the seat.

When she reached the floor, she turned back into a cat, and stood stock
still. I apologized and held her close. I let her have some licks of the
plain yogurt I was having.

Later, Buster came by and hopped up on my lap, loving the attention he was
getting as I routinely checked him for spots to brush or clip. Very much
unlike Dot, Buster doesn't understand treats. But I thought it wouldn't do
him any harm to get a little bit of yogurt. I smeared a tiny dollop right
under his nose.

Buster paused at this odd smell. Then, as I expected, he instinctively
licked off the sour-creamy spot. He looked absolutely *shocked* for a
moment at the taste in his mouth, and he bounded out the room in
practically one jump, galloping at top speed in the direction of his water
bowl.