Notes: 1  In 1997, MLB retired Jackie Robinson's number 42 meaning no other player in MLB could ever wear it. However, it was grandfathered to anyone who was currently wearing the number. 2  Mariano Rivera is the only Yankee to appear as an active player while wearing his retired number.
The Ordovician Period. The Ordovician Period lasted almost 45 million years, beginning 488.3 million years ago and ending 443.7 million years ago.* During this period, the area north of the tropics was almost entirely ocean, and most of the world's land was collected into the southern supercontinent Gondwana.
The Rise of The Cephalopods. The Ordovician Period is the second period of the Paleozoic Era. Ordovician rocks were first found in Wales, so its name comes from a tribe of people who once lived in the area where the rocks were found.The Ordovician began about 490 million years ago and lasted for about 47 million years.The Continents-Gondwanaland. Gondwana was a huge supercontinent during the Ordovician Period. It contained the modern continents of Australia, Africa, Southern Europe, Antarctica and South America.he Continents-North America and Europe. Modern continents of North America, Western Europe and Northern Europe were located in the tropics, on or near the equator. These land areas were sometimes covered with water and sometimes not. Toward the end of the Ordovician Period more of the land was out of the water.