jQuery animation/blinking code?
you can chain the delay and switchClass to $elements and take the $("#container").find(".animation"); outside the function like this       

function startAnimation($elements) {
$elements.switchClass("mc-ylw-blk", "mc-blk-ylw", 0)
      .delay(500).switchClass("mc-blk-ylw", "mc-ylw-blk", 0)
      .delay(250).switchClass("mc-ylw-blk", "mc-blk-ylw", 0)
      .delay(250).switchClass("mc-blk-ylw", "mc-ylw-blk", 0)
      .delay(500).promise().done(function () { 
          startAnimation($elements);
      });
}
var $elements=$("#container").find(".animation");
if ($elements.length) {
    startAnimation($elements);
}       


http://jsfiddle.net/Y95rU/1/