Geology Europe and North America collided in this period, forming the Caledonian mountains in present-day Canada. Animal Life In the water, there were scorpion-like animals akin to now-extinct marine arthropods called euyperiods. Trilobites, which were plentiful in both the Cambrian and Ordovician periods, decreased in variety and number. Seas were full of coral reefs, cephalopods, and jawed fish. Reefs even covered what is now parts of Wisconsin, Illinois, Indiana, Ohio, New York, Lake Michigan, Lake Huron, and Lake Erie. Plant Life The Silurian Period was the first period with life moving onto land. It did this in the form of simple plants called psilophytes, with a vascular system for circulating water.

Euyperiods- 3 meter long sea scorpions

The first plants to come on land

Paleozoic Era: Silurian Period