The first organisms on Earth are said to be anaerobic.  What does this tell you about early Earth’s atmosphere?

Darwin conducted much of his research on

What is the term for a feature that allows an organism to survive better in its environment?

What were thought to be the first organisms?

Explain how oxygen got into the atmosphere.

A principle that states that the same geographical processes that occur today occured in the past.

The finches on the Galapagos island were similar in form except for variations of their beaks. Darwin observed that these variations were useful for

Feature that is similar in structure in different organism but has different functions

Remnant of an organ or structure that had a function in an early ancestor

Features that have the same function, but may not look alike

Examples include the wing of a bat and the hand of a human

Examples include the wing of an ostrich and the appendix of a human

Examples include the wings of a hummingbird and the wings of a moth

Bart tells Susie that his family has evolved to withstand colder temperatures.  He says, “My family has always lived in regions of the world that are cold, so we RARELY get cold.  My family has evolved to the low temperatures!”  Is Bart’s statement true?

Organisms are constantly adapting so that they