Early Earth History Answers

The formation of the moon may have caused the Paleozoic extinction.

Early land animals had to return to the water to reproduce.

The change in environments that may have occurred at the end of the Paleozoic Era may have been caused by ____.a.mass extinctionsc.plate tectonicsb.evolution of the dinosaursd.the beginning of an ice age

The development of ____ factored in the development of complex organisms.a.ozonec.cyanobacteriab.oxygend.all of the above

Geologic events that occurred during the Paleozoic Era include mountain building and volcanic activity.

Early land animals had gills as well as lungs.

The Precambrian time period is the largest on the geological time scale.

The geological time scale is divided up and organized according to what life forms existed on earth.

Little is known about much of Earth’s early history because ____.a.Precambrian rocks have been deeply buriedb.Precambrian rocks have been changed by heat and pressurec.Precambrian soft-bodied life-forms weren’t often preserved as fossilsd.all of the above