1. What was the composition of Earth’s atmosphere shortly after its formation?

2. What is the current atmospheric composition?

3. What caused the changes in atmospheric conditions? How did life on earth
first develop?

4. How do we know that this is likely how life formed? Introduce the idea of
the Miller-Urey Experiment

Hummingbirds drink nectar from flowers, while robins eat plant seeds. what does this reduce?

What are the characteristics of living things

(drag each tile to the correct location.) categorize each term as something that is typical of a scientific theory, a scientific hypothesis, or both. - a tentative statement used to guide scientific investigations. - makes predictions about future events. - can be tested by many independent researchers. - based on observations of natural phenomena. - a well-established, highly reliable explanation.