1. The Eras of Geologic Time
... interior, leaving sedimentary deposits to mark their own invasions. By late Paleozoic, continental collisions formed the super continent Pangaea and resulted in some of today's mountain chains. One of the most important features of this period is the appearance of nearly all of the invertebrate animal phyla in abundance. A few fishlike invertebrates and vertebrates appeared in the Cambrian and Ordovician. Scorpions, land invertebrates, amphibians, ... major division of geologic time from sixty five to two hundred and twenty five million years ago and is put into three geologic time perio...
- Word Count: 1841
- Approx Pages: 7
- Grade Level: Undergraduate