Biology w/Earth Systems Oct 12 & 13 Get out your journal and a pencil. Turn in your test corrections. Get out your Sea Floor Spreading CER—hold on to it.

Warm Up for Oct. 12 & 13 What is your best estimate for when the following events happened on Earth? Estimate how many years ago (thousands, millions, billions?) Formation of Earth Existence of Dinosaurs First Plants Existence of Humans

Sea Floor Spreading CER Switch papers with the person across from you. In yellow highlighter, highlight any evidence that is specifically cited from the article. In green highlighter, highlight any evidence that is specifically cited from the diagram. In pink highlighter, highlight what you think is their reasoning that ties the evidence to the claim.

Unit Two: Evolution You will learn: How evolution happens (natural, artificial, and sexual selection) Evidence for evolution (fossil record, homologous structures, embryology) Relative and Radiometric Dating How physical properties of Earth change Earth’s formation and early history

Learning Targets! I can make a model of the evolutionary timeline I can describe physical changes that have occurred on Earth and evidence for those changes

Major Events on Earth Place these events in order With your elbow partner: Get two white boards and place them side by side. Place the cards in order. Under each event, write the date you think it occurred (between 15 bya and today) First simple cells Universe formed First oxygen First plants First complex cells First animals Earth formed First oceans Dinosaur extinction

Cosmos Video Guide Wrap-Up Big Idea: Earth’s physical characteristics are constantly changing. Give 3 examples of this idea from the video, including how we know (the evidence).

Back to your timeline… How close were you? Universe formed- 15 bya Earth formed- 4.6 bya First oceans- 3.8 bya First simple cells- 3.6 bya First oxygen- 2.2 bya First complex cells- 1.7 bya First animals- 700 mya CAMBRIAN EXPLOSION!- 545 mya First plants- 470 mya PERMIAN EXTINCTION!- 250 mya Dinosaur extinction- 65 mya First humans- 200,000 years ago

The Cambrian Explosion 545 mya, the fossil record shows an explosion of life! High oxygen and no predators = evolution and survival of bizarre sea creatures

Some Cambrian Animals