Here On Earth: An Argument For Hope

by Tim Flannery

Studies of the Y-chromosome reveal that all people alive today are descended from a single male who lived in Africa around sixty thousand years ago.55 This genetic Adam, it’s reasonable to deduce, was dark-skinned, tall, slender, and possessed epicanthi, the folds over the corner of the eyes commonly seen in people from Asia.

The tale told by mitochondria confirms our African origin. But there is one startling difference between our male and female ancestry: mitochondrial DNA tells us that all people alive today can trace their ancestry to an African woman who lived at least a hundred and fifty thousand years ago. Adam and Eve, it seems, never met, being separated by ninety thousand years.56

It’s a remarkable fact that, despite our huge population, humans are one of the most genetically uniform of mammal species, there being more genetic diversity in a random sample of about fifty chimpanzees from west Africa than in all seven billion of us.

while agricultural societies are powerful, they are composed almost entirely of incompetent individuals.

we continue as we are, within this century we stand at risk of exterminating up to six out of every ten living species.