<p> Kendrick FebruaryKendrick 27, February2010 Period 27, 22010 Period 2</p><p>GeologicGeologic Time TimeScale Scale Use with UseChapter with 14,Chapter Section 14, 14.1 Section 14.1 </p><p>1. What is the basis of the Geologic Time Scale? </p><p>The basis is correlation based time units of rock formations by the index fossils they contained. 2. Describe the divisions of the Geologic Time Scale. Precambrian era- life begins Paleozoic era- lizard like animals appear Mesozoic era- The time of dinosaurs and the first mammals Cenozoic era- mammals and humans evolve</p><p>3. During what era and at approximately what date does fossil evidence suggest life had evolved on Earth? What form of life was this? </p><p>During the Precambrian era around 4000 million years ago was when life first started. Very small hard shelled creatures lived underwater</p><p>4. What forms of living things characterized the Cambrian period?</p><p>The creatures that lived in the Cambrain period were invertebrates. Invertebrates have no backbones</p><p>Co 5.py During what era did the first vertebrates evolve? What were these vertebrates? rig ht Vertebrates© evolved during the Ordovician period. The first vertebrates were the Gl Orthoceras,en Brachiopods, and crinoids. co e/ M cG 6.ra The dinosaurs and many other species became extinct in a relatively short period of time that w- marksHi what is called the K-T boundary, which stands between the Cretaceous and Tertiary periods.ll, About how long ago did the dinosaurs become extinct? a di vis Theio Dinosaurs became extinct about 65 million years ago. n of 7.Th Imagine you found a fossil of a bird that dates to 213 million years. Why would this find be e astonishingM to scientists? cG ra Itw- would be astonishing because the oldest known bird fossil is 150 million years old Hi (Archaeopteryx)ll Co m 8.pa Suppose a geologist finds a layer of rock that can be dated to 320 million years ago. nie Layerss, from which periods would be expected to be above and below the newly discovered In layer?c. </p><p>The Pennsylvanian and Mississippian periods.</p><p>TRANSPARENCYRETEACHING WORKSHEET SKILLS TRANSPARENCY 23 BIOLOGY: TheMASTER Dynamics 23 of BIOLOGY: Life RETEACHING The Dynamics SKILLS of Life </p>