Summer work Chapters 1, 6 and 25 History of Life on Earth Fig 25-UN8 Millions of years ago (mya) 1.2 bya: First multicellular eukaryotes 2.1 bya: First eukaryotes (single-celled)…

Conditions on early Earth made the origin of life possible Chemical and physical processes on early Earth may have produced very simple cells through a sequence of stages:…

Chapter 22 The Origin and History of Life Early Evolution The universe began with the Big Bang about 13.7 bya (billion years ago) Our solar system began about 4.6 bya The…

Big Idea 1 Big Idea 1 Ch. 26 â The Tree of Life Geologic history and biological history have been episodic, marked by revolutions that opened many new ways of life Conditions…

Big Idea 1 Big Idea 1 Ch. 26 â The Tree of Life Geologic history and biological history have been episodic, marked by revolutions that opened many new ways of life Conditions…

A rainy day 2.7 billion years ago reveals surprising notions of the early Earth's atmosphere Air density limited 2.7 billion years ago limited to twice present levels…