Smithsonian Institution
National Museum of Natural History: Paleobiology: The Ordovician Period
Journey into the past while reading this comprehensive overview of the Ordovician Period that covers topics such as reef ecosystems, Paleozoic Fauna, fossil evidence, and climate and plate tectonics.
Science Struck
Science Struck: Relative vs. Absolute Dating
Explains what relative and absolute dating are and some different methods used for each. A Venn diagram is presented showing what characteristics they share and how they differ.