How is radioactive dating used to interpret the fossil record

The physical properties of the ice and of material trapped in it can be used to reconstruct the climate over the age range of the core.

Discoveries of Galileo -Moon surface= rough and uneven - the surface is covered with craters, mountains and valleys -sunspots, landscape on moon, Jupiter moons, jail, ideas of universe -supports Copernican idea that Earth and other planets orbit the Sun 10.

Additional information from articles Enables to organizes time into meaningful “chunks”, context to understand time frames -Eon: the largest of time units (Hadean, Archaen, Proterozoic, Phanerozoic) -Precambrian: unit of geologic time consisting of the first three eons during which Earth formed and became hospitable to life; makes up nearly 90% of geologic time -Era: ten-hundreds of millions of years in duration (Paleozoic, Mesozoic, Cenozoic) -Periods: tens of millions of years in duration -Epochs: hundreds of thousands to millions of years in duration -Bascially: Eon -Extinction events determine the divisions of eras and periods on the geologic time scale -Cenozoic era is divided into both periods and epochs -Geologists study fossils for paleo ecology where they can find out the patterns of life, predict and/or protect future -We live in Holocene epoch, Quaternary period and Cenozoic era -Major divisions of Earth’s history are Eras -Each major division may be divided into periods -The Cenozoic Era is divided into epochs -Clues to which organisms lived in different eras are found in fossils -A gradual change in life-forms over time is organic evolution -After major changes in Earth’s environments, species either died out or adapted -Organisms with traits that are suited to an environment survive by the process of natural selection -Plate tectonics caused collision and separation of continents -Many species adapted or became extinct because plate tectonics caused their environments to change when the continents collided or separated -Protorozoic era lasted the longest -Hadean era is the oldest Order of which species appeared on Earth: What happened to all of the continental plates near the end of the Paleozoic Era? Key Concepts in development of Geologic Time -Up to late 1700s, Earth history was based on biblical interpretation only –Catastrophism: a belief that the varied landscapes were created by great catastrophes in history; e.g.

Isotopes are important because each radioactive element decays at a constant rate.