Big History: A Summary of Evolution of Life on Earth

The first organisms, simple photosynthetic bacteria, appear in sediments about 3.5 billion years old, only about a billion years after the planet was formed. These single cells were all that occupied the Earth for the next two billion years, after which we see the first simple “eukaryotes”: organisms having true cells with nuclei and chromosomes. Then, around 600 million years ago, a whole gamut of relatively simple but multicelled organisms arise, including worms, jellyfish, and sponges....

 Science Takes No Sides--and No Prisoners

The great thing about science is that it takes no sides—and no prisoners. Once you know which research to trust, the big picture emerges and myths fade away. To gain my trust, research must pass my “grump factor.” To make it into this book, studies must first have been published in the refereed literature and then successfully replicated. Some results have been confirmed dozens of times. Where I make an exception for cutting-edge research, reliable but not yet fully vetted by the passag...