The search for life’s stirrings
Scientists studying how life arose on Earth are stumped by several key steps in that eventual process, but a Harvard scientist studying the earliest cells says that seemingly intractable problems in this field have sometimes proved to have simple, even elegant solutions. Those pondering the earliest stirrings of life expect that it will either turn out to be easy to create and a natural outgrowth of the primordial conditions found on planets like Earth: rocky, not too hot, not too cold, with water and other key elements. If that’s the case, the rapid acceleration of discoveries of extrasolar planets would mean there are potentially millions of other worlds that are Earth-like enough for life to arise. Or, life may be hard to get going, requiring a precise combination of conditions and chemicals that were present on Earth, perhaps fleetingly and only once. If that’s the case, such conditions may be difficult to...