Life on other planets will be extremely different from us. Consider the following thought experiment. Imagine a planet like earth, where evolution follows exact

Life on other planets will be extremely different from us. Consider the following thought experiment. Imagine a planet like earth, where evolution follows exactly the same path, with the same species, the only difference being that it is 2% older. The earth is 4.5 Billion years old, so 2% is 90 million years. According to Wikipedia [1] 90 million years ago is about the time placental mammals appeared. So in that time frame evolution pulled mammals in directions as diverse as bats, whales, and elephants. So the human decedents on the other planet will not look at all like us... [1] http://en.wikipedia.org/wiki/Timeline_of_evolutionary_history_of_life http://en.wikipedia.org/wiki/Timeline_of_evolutionary_histor...