Name Date Class s2

Kendrick FebruaryKendrick 27, February2010 Period 27, 22010 Period 2

GeologicGeologic Time TimeScale Scale Use with UseChapter with 14,Chapter Section 14, 14.1 Section 14.1

1. What is the basis of the Geologic Time Scale?

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

3. During what era and at approximately what date does fossil evidence suggest life had evolved on Earth? What form of life was this?

During the Precambrian era around 4000 million years ago was when life first started. Very small hard shelled creatures lived underwater

4. What forms of living things characterized the Cambrian period?

The creatures that lived in the Cambrain period were invertebrates. Invertebrates have no backbones

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.

The Pennsylvanian and Mississippian periods.

TRANSPARENCYRETEACHING WORKSHEET SKILLS TRANSPARENCY 23 BIOLOGY: TheMASTER Dynamics 23 of BIOLOGY: Life RETEACHING The Dynamics SKILLS of Life