Life

What is life? A thing of dynamism, fragility, beauty, danger and evanescence, gushing forth from a single source, to be sure. But here the certainties end: what does it take to be alive? Are viruses and prions alive? How many branches are there on our tree? The harder we look, the more complexities we find. With the recent creation of synthetic bacteria (Mycoplasma laboratorium, seen issuing from its own domain) even the surety of a single common ancestor disappears into smoke.