Greenland sharks have existed for hundreds of millions of years through their ancient lineage while Saturn’s iconic rings are believed to have formed far more recently, possibly only 10 to 100 million years ago.
That means sharks were already swimming in Earth’s oceans long before Saturn wore its most famous feature.
...which makes me wonder what the odds are of earth getting a ring once Kessler kicks off. But I suppose most of that junk is just going to burn up in the atmosphere and/or crash on somebody's house.